Gunn's 3.8L Single Port to Splitport V6 DIY

gunn

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Sep 22, 2023
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SF , CA
Vehicle Details
95 T-bird with 5.0and m5r2 swap for lemons
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S4Gunn's Split-port DIY & Lessons Learned


Q: Why do a splitport upgrade? For starters, a 99-04 Mustang is rated for 193HP/225lb-ft while the same 3.8L block in the 89-97 Mustang only made 140HP/215lb-ft of torque. Given that V6 Mustangs are plentiful, the parts are cheap so this is one of the best bangs for the buck you find find.

In my case, I needed a cheap yet reliable way to boost the HP of my 24 Hours of Lemons track car (they give you a residual after every race so I made my intentions clear to the judges). Plus, I also didn’t want to upset the weight & balance of my track car by dropping in a 302 engine because after 2 races, the suspension and brakes are quite well suited for my existing block.

The following post will document the lessons I learned in my upgrade of my 1995 Ford Thunderbird 3.8L from a single port to a Split-port manifold/heads for the 24 Hours of Lemons. This might not line up 100% with what you need to do but I’ve tried to compile ALL the information I’ve collected over the 9 months of this project so you should have a good idea of what you want to do for this upgrade.. Please also note that I use the term ECU and PCM interchangeably here.

Q&A
Q: How much time will this take?

A: Since this is my track car and I didn’t have any future races committed, I took my time here. According to my records, this project took approximately 90 hours of my time on evenings/weekends for all the on-vehicle work and including several times when I repeated a step to correct an error and/or solve the problem in a more effective manner. All of this is documented below so a more talented mechanic should be able to bang out this project in a weekend or two with sufficient preparation (i.e.: finishing up all the fuel rail and intake manifold modifications in advance). The upgrade and extra fabrication for the Windstar intake and the tuning/analysis to figure out why the engine didn't rev beyond 4K RPM tool up another ~58 hours. Seriously.

STATUS 2/16/2013: Project Complete. I finally tracked down my rev issue -- my ignition timing was screwed up. I'm now working on the cars "theme". Next upgrade: 4.2L (if I can find one) or 302 V8 (which introduces all sorts of new and exciting problems to solve).
LESSON LEARNED IN MARCH 2013: This engine lasted 19 laps before blowing up. Before you dump a pile of effort into a splitport upgrade, consider what base block you are working with and how many miles are on it. My engine, a reman block with ~60K miles on it, did NOT like being rev'd to 5K RPMs repeatedly on the track and blew up in spectacular fashion. For your own piece of mind, consider refreshing the bottom end (i.e.: check tolerances, new bearings, new rings and re-bore if necessary). Had we refreshed our V6 block before tackling this splitport upgrade, our V6 would probably still be running and we wouldn't be trying to not blow up a V8 today.

BEFORE YOU BEGIN
Read up on the following threads. This will help you figure out what parts you should be looking for with your specific project. As you can see, there is a bunch of data online about splitport swaps but there are still improvements that can be made (SixPackStang's thread is probably the most comprehensive but still doesn't outline most of the "gotchas" for folks (like me) who have never tackled a project like this before.

http://3.7mustang.com/vb/f5/sixpackstangs-official-split-port-swap-post-95288/
http://3.7mustang.com/vb/f5/3-8-single-port-4-2-split-engine-swap-pictures-videos-266219/
http://forums.tccoa.com/showthread.php?t=6680 -- for 4.2L swap but many of the principles are the same with a 3.8L Split-port swap.

I also collected the factory shop manuals for the related head gasket replacement procedures for both engine blocks.
  • My instructions for the 1995 Thunderbird 3.8L came from my Ford Shop Manual. At the time of this DIY creation, you could find these manuals (often with the EVTM) for ~$15 on eBay.
  • My instructions for the 2001 Mustang 3.8L came from the local library. With my library card, the Palo Alto library system gives you online access to EBSCO’s Auto Repair Reference Center (ARRC). It’s kind of like the Mitchell system independent auto shops use. Other libraries limit access to their physical libraries only so YMMV here.

Parts Used
  • 2001 Mustang Split-port Heads: since these are aluminum heads going on an iron block, do yourself a favor and take them to a machine shop to have the bottoms honed flat before installation.
  • 2001 Mustang Split-port upper intake manifold. Modifications suggested (see seperate section below).
  • OPTIONAL: Over the course of my research, I also found out that the Windstar upper intake provides an improvement in heat soak (it’s plastic vs. aluminum) and airflow for an overall gain of ~7-15HP. See below for the Addendum.
  • 2001 Mustang Split-port Lower intake manifold. Modifications required (see modifications section)
  • ALTERNATIVE: 4.2L upgrade
  • Advantage: While your HP won’t increase much, you will allegedly reach “near V8 levels” of torque without the weight penalty of a 5.0L engine (the V8 that will readily mate with my existing M5R2 transmission).
  • From my research, I found that the 4.2L engine uses the same block but different crank, pistons, and connecting rods.
  • Problem 1: you will need to muck with the block. I have a perfectly working 3.8L engine before the splitport upgrade. If I was going to muck with the block, at that point, it will probably be more cost effective in terms of time for me to buy an entire 4.2L engine and swap the engine over – leaving my original splitport engine as a “spare”.
  • Problem 2: you need to find the parts and/or engine. I never found a good deal here.
  • ¼” diameter solid Aluminum Rod to block off butterfly valves. I needed approximately 13” per side and I purchased this from Orchard Supply Hardware for ~$13.50

  • 2001 Mustang Split-port Engine Wiring Harness:
    - I needed the IACV and Throttle Position Sensor (TPS) connectors
    - You may also need the fuel injector plugs if your harness plugs are different from your chosen fuel injectors.

  • 2001 Mustang Split-port Fuel Injectors + Adapters
  • There are two different styles of fuel injectors EV1 and EV6 – one’s fat and one’s skinny.
  • You don’t care about the size as both are compatible with the Split-port intake manifold but the connectors might NOT be compatible as there are two standards: JETRONIC and USCAR.
  • Using the 19# injectors over the stock 14# injectors was recommended to me because they have a spray pattern that matches the Split-port manifold; from my calculations it also looks like the 14# injectors are close to being maxed out in the original non-Split-port application.
  • There are 2 adapters on the market -- hard plastic adapters or more homemade looking ones with exposed wires between the connectors. If you have the budget for buying adapters vs making your own, you might as well go with the hard plastic adapters. After all, you can always make your own adapters by splicing the fuel injector plugs from the Split-port harness to the car’s existing harness if you are encountering budget limitations.
  • I bought the following (8pack) set of Jetronic to USCAR adapters (Ford Racing Part# M-14464-A8) from buyfordracing.com.
  • Make sure you confirm that the adapters work for your chosen style of injector and harness (you don’t want to get adapters for the exact opposite of your application).
  • Finally, In order to run 19# injectors in a car that originally shipped with 14# injectors, you will need to do an ECU reflash. I explained what I needed and Don @ Lasota racing was willing to burn me an SCT chip to match my needs and maximize the value for this Split-port upgrade.
  • NOTE: This project will work with the stock ECU and stock 14# injectors from your old intake – you just won’t get the full advantage of the Split-port swap. In case you decide to stick with the 14# injectors though , here's a word of warning about the SK "injector rebuild" kit model SK57 -- the included pintle caps have the wrong sized opening. From what I can tell, they work with the 30# injectors that come with early SuperCoupes. I rebuilt my 14# injectors to use with my spare engine block and in doing so I needed to reuse my old pintle caps.

  • 2001 Mustang Throttle Body, TPS, and IACV
  • The Split-port throttle body is a different shape
  • The Split-port TPS is mounted in a different orientation and has a different sensor. You need a TPS sensor that opens from 0-5V in a clockwise fashion (Windstar is CCW. You may also find yourself building an adapter place if the mounting holes are 90degrees offset (I did).
  • The Split-port IACV mounts to the throttle body and not the intake manifold and has a different connector

  • Split-port compatible Return Style Fuel Rail
  • Original Tbird Fuel Rail: donates the Fuel Pressure Regulator (FPR) assembly
  • 1 or 2 Splitport Fuel Rails. Going with two costs slightly more but saves you potential points of failure (see details below)
  • Fuel Rail Buying Tip: when purchasing the fuel rail second hand from the internet, make sure to confirm if the seller will send you the fuel pressure sensor (FPS). Even if you won’t be using the FPS to regulate the fuel pressure in the system, you need the FPS to plug the hole in the fuel rail. Since I wanted to minimize the DIY points of failure in my fuel rail system, I had to go searching onto the internet for a replacement FPS for the one that the supplier of my second rail didn’t send to me.
  • SpringLock to Barb Adapters: There are multiple ways to solve this Problem. I actually tackled it twice. In my final iteration (after I realized that outside of injectors and the ECU the fueling system is a budget exempt category in Lemons), I purchased the following:
    - Ron Morris Performance Female Supply Springlock to Barb Adapter RM9141
    - Ron Morris Performance Female Return Springlock to Barb Adapter RM9142
    - (2) splitport compatible returnless fuel rails
  • You will need good quality, SS hose clamps. I found that #4 SS clamps are available for ~$2 in “10pc contractor packs” from Lowes.
  • Fuel Hose:
  • You also need J30R9 fuel injection hose (vailable in bulk from Autozone). J30R7 hose is significantly cheaper and more readily available but is NOT rated for the pressures found in FI systems.
  • Alternative: the “proper” hose recommended in other DIYs is to use Aeroquip FC332 socketless hose and fittings. That stuff is spendy so to keep with the spirit of the “24 Hours of Lemons”, I went with the J30R9 hose.
  • Cost Saving DIY Alternative #1: Build your own Springlock to Barb Adapters
  • Supply Line Springlock
    - Female Springlock Connector from original fuel rail
    - Steel Tube Nut model BLF-15C-5 from Autozone (sold in 5 pack): 3/8” Tube size, 5/8”-18 inverted thread size
    - Female 3/8” Flare to 3/8” male Barb coupling (Orchard Supply Hardware)
  • Return Springlock to Barb Adapter
    - Female Springlock Connector from original fuel rail
    - Steel Tube Nut model BLF-14C-5 from Autozone (sold in 5 pack): 5/16" Tube Size, 1/2-20 inverted thread size
    - Female 3/8” Flare to 3/8” male Barb coupling (Orchard Supply Hardware)
  • Cost Saving DIY Alternative #2: acquire one from a First Gen Ford Ranger
    - A friend and fellow TCCOAer (jco1385) who followed my splitport build reported that you can find the very same return springlock to barb fitting I purchased from Ron Morris on a First Gen (89-92) aka "square body" 4cyl Ford Ranger
    - You can easily cut this fitting off with some heavy duty snips and you can find it on the driver's side underneath the intake pipe towards the rear
    - A 2nd gen Ford Ranger or one of the V6 first gens might have a similar fitting but I don't have confirmation of this so please go to the junkyard and if you find one, let me know and I'll update this DIY.

  • Triple 3/8” male Barb Tee (ACE Hardware)
  • See Fuel System Modifications Section for more details

  • 2001 Mustang V6 throttle cable / accelerator cable
  • This one threw me for a loop as I didn’t see it mentioned in other Split-port threads/DIYs.
  • The end connector (how the accelerator cable physically attaches to the throttle body) is different) between my tbird and the mustang’s throttle body.
  • The V6 mustang’s cable is also 36” and the tbird’s was 40”. A new one is only ~$30 if you look but please note that for my 2001 intake manifold and throttle body, I needed a cable specifically for a 2001-2004 V6 mustang.
  • The mounting bracket is also different. I also had to purchase one for a 01 Mustang (came with my second fuel rail).

  • 2001 Mustang Upper and Lower Intake Manifold Gaskets

  • 2001 Mustang Thermostat Housing, 2001 Mustang upper radiator hose, and 2001 Mustang thermostat gasket.
  • I was originally hoping to re-use the 95 tbird’s original upper radiator hose and thermostat housing because I had modified the upper radiator hose to allow for additional coolant injection under pressure (a lemony way to keep your car on the track with minimal pitstops if it starts consuming coolant). However, the original thermostat housing hits the coolant pipe that wraps around the intake manifold and the original molded cable won’t reach the 2001 Mustang’s thermostat housing.
  • There are TWO upper radiator hoses at Autozone that will work for this application (Dayco #E72077 and Dayco #D71909). You want to go with the Dayco #D71909 hose as it places the radiator hose just a tad farther away from the tensioner pulley. After a few hours of driving, i found a groove in my E72077 hose that would have cause more serious problems on the track.
  • Your old thermostat is reusable here but I found the thermostat gaskets to be a slightly different shape.

  • O-rings for coolant hard pipes: I found two cooling pipe related o-rings that merit replacing:
  • One was for the hard pipe that goes into the top of the waterpump. My waterpump actually came with the necessary o-ring.
  • The second one is for the smaller hard coolant pipe that attaches to the back of the lower intake manifold. I found a compatible o-ring at Lowes in the plumbing section as the only ones Autozone carried with the necessary inner diameter were too thick. 1/2" ID, 5/8" OD, Size #28, comes in a 2-pack: http://www.lowes.com/pd_174733-72906-SC0529_0__?Ntt=174733&productId=3137361&rpp=16

  • Optional: Bypass the heater core with a 180 degree U-shaped tube to connect them. NOTE: one of the coolant tube openings is slightly larger than the other one. Dayco Part# B87629

  • http://www.autozone.com/autozone/parts/_/N-8gd8t?itemIdentifier=10284_0_0_
  • Diagram (validated in this thread http://forums.tccoa.com/showthread.php?t=140583) of the coolant flow for this engine here.
    tbird_38Lcoolantflowdiagram.jpg


  • 1995 Thunderbird Intake Tube - modified
    - More details below in the Re-Assembly Section

  • 2001 Mustang Head Gasket Set
    - Fel-Pro multi layer steel gaskets were recommended.
    - Copper gaskets are apparently available but I didn’t explore this further as they are a) way outside the 24 Hours of Lemons budget and b) require decking of the engine block.

  • 1995 Ford Thunderbird Head Bolts
  • Buy the head studs/bolts that match your engine block – not the Split-port heads
  • After 96, there was a change that was made that make the long studs just a little too short. I confirmed this by testing the length that the old head bolts protruded both the Split-port heads and the old heads while on my workbench. They were the same so therefore any change that merits a difference in headbolt length would need to be in the block.
  • Alternative: Head studs
  • Head Studs are available from ARP directly that work for 95 and older blocks.
    - 153-4203 (12pt nuts)
    - 153-4001 (6pt nuts)
  • For 95 and older blocks, you can also buy the head studs for a "Chevy 2.8L V6" and save some money. They are identical and cheaper.
    - 233-4303 (12pt nuts -- Chevy 2.8L V6 application)
    - 233-4003 (6pt nuts -- Chevy 2.8L V6 application)
  • For 96 and newer 3.8L engines, Tom @ maronav6racing.com commissioned ARP to make the right studs but they are pricey ($230+ when I last looked)
  • My thread on this subject: http://3.7mustang.com/vb/f5/q-about-3-8l-head-bolts-studs-95-tbird-block-01-mustang-heads-266472/
  • My Decision: Given the price, I just went with FelPro Head Bolts: FEL-PRO Part # ES72131 (for 94-95 mustang and 89-95 tbird)
 
S4Gunn's Split-port DIY & Lessons Learned


Q: Why do a splitport upgrade? For starters, a 99-04 Mustang is rated for 193HP/225lb-ft while the same 3.8L block in the 89-97 Mustang only made 140HP/215lb-ft of torque. Given that V6 Mustangs are plentiful, the parts are cheap so this is one of the best bangs for the buck you find find.

In my case, I needed a cheap yet reliable way to boost the HP of my 24 Hours of Lemons track car (they give you a residual after every race so I made my intentions clear to the judges). Plus, I also didn’t want to upset the weight & balance of my track car by dropping in a 302 engine because after 2 races, the suspension and brakes are quite well suited for my existing block.

The following post will document the lessons I learned in my upgrade of my 1995 Ford Thunderbird 3.8L from a single port to a Split-port manifold/heads for the 24 Hours of Lemons. This might not line up 100% with what you need to do but I’ve tried to compile ALL the information I’ve collected over the 9 months of this project so you should have a good idea of what you want to do for this upgrade.. Please also note that I use the term ECU and PCM interchangeably here.

Q&A
Q: How much time will this take?

A: Since this is my track car and I didn’t have any future races committed, I took my time here. According to my records, this project took approximately 90 hours of my time on evenings/weekends for all the on-vehicle work and including several times when I repeated a step to correct an error and/or solve the problem in a more effective manner. All of this is documented below so a more talented mechanic should be able to bang out this project in a weekend or two with sufficient preparation (i.e.: finishing up all the fuel rail and intake manifold modifications in advance). The upgrade and extra fabrication for the Windstar intake and the tuning/analysis to figure out why the engine didn't rev beyond 4K RPM tool up another ~58 hours. Seriously.

STATUS 2/16/2013: Project Complete. I finally tracked down my rev issue -- my ignition timing was screwed up. I'm now working on the cars "theme". Next upgrade: 4.2L (if I can find one) or 302 V8 (which introduces all sorts of new and exciting problems to solve).
LESSON LEARNED IN MARCH 2013: This engine lasted 19 laps before blowing up. Before you dump a pile of effort into a splitport upgrade, consider what base block you are working with and how many miles are on it. My engine, a reman block with ~60K miles on it, did NOT like being rev'd to 5K RPMs repeatedly on the track and blew up in spectacular fashion. For your own piece of mind, consider refreshing the bottom end (i.e.: check tolerances, new bearings, new rings and re-bore if necessary). Had we refreshed our V6 block before tackling this splitport upgrade, our V6 would probably still be running and we wouldn't be trying to not blow up a V8 today.

BEFORE YOU BEGIN
Read up on the following threads. This will help you figure out what parts you should be looking for with your specific project. As you can see, there is a bunch of data online about splitport swaps but there are still improvements that can be made (SixPackStang's thread is probably the most comprehensive but still doesn't outline most of the "gotchas" for folks (like me) who have never tackled a project like this before.

http://3.7mustang.com/vb/f5/sixpackstangs-official-split-port-swap-post-95288/
http://3.7mustang.com/vb/f5/3-8-single-port-4-2-split-engine-swap-pictures-videos-266219/
http://forums.tccoa.com/showthread.php?t=6680 -- for 4.2L swap but many of the principles are the same with a 3.8L Split-port swap.

I also collected the factory shop manuals for the related head gasket replacement procedures for both engine blocks.
  • My instructions for the 1995 Thunderbird 3.8L came from my Ford Shop Manual. At the time of this DIY creation, you could find these manuals (often with the EVTM) for ~$15 on eBay.
  • My instructions for the 2001 Mustang 3.8L came from the local library. With my library card, the Palo Alto library system gives you online access to EBSCO’s Auto Repair Reference Center (ARRC). It’s kind of like the Mitchell system independent auto shops use. Other libraries limit access to their physical libraries only so YMMV here.

Parts Used
  • 2001 Mustang Split-port Heads: since these are aluminum heads going on an iron block, do yourself a favor and take them to a machine shop to have the bottoms honed flat before installation.
  • 2001 Mustang Split-port upper intake manifold. Modifications suggested (see seperate section below).
  • OPTIONAL: Over the course of my research, I also found out that the Windstar upper intake provides an improvement in heat soak (it’s plastic vs. aluminum) and airflow for an overall gain of ~7-15HP. See below for the Addendum.
  • 2001 Mustang Split-port Lower intake manifold. Modifications required (see modifications section)
  • ALTERNATIVE: 4.2L upgrade
  • Advantage: While your HP won’t increase much, you will allegedly reach “near V8 levels” of torque without the weight penalty of a 5.0L engine (the V8 that will readily mate with my existing M5R2 transmission).
  • From my research, I found that the 4.2L engine uses the same block but different crank, pistons, and connecting rods.
  • Problem 1: you will need to muck with the block. I have a perfectly working 3.8L engine before the splitport upgrade. If I was going to muck with the block, at that point, it will probably be more cost effective in terms of time for me to buy an entire 4.2L engine and swap the engine over – leaving my original splitport engine as a “spare”.
  • Problem 2: you need to find the parts and/or engine. I never found a good deal here.
  • ¼” diameter solid Aluminum Rod to block off butterfly valves. I needed approximately 13” per side and I purchased this from Orchard Supply Hardware for ~$13.50

  • 2001 Mustang Split-port Engine Wiring Harness:
    - I needed the IACV and Throttle Position Sensor (TPS) connectors
    - You may also need the fuel injector plugs if your harness plugs are different from your chosen fuel injectors.

  • 2001 Mustang Split-port Fuel Injectors + Adapters
  • There are two different styles of fuel injectors EV1 and EV6 – one’s fat and one’s skinny.
  • You don’t care about the size as both are compatible with the Split-port intake manifold but the connectors might NOT be compatible as there are two standards: JETRONIC and USCAR.
  • Using the 19# injectors over the stock 14# injectors was recommended to me because they have a spray pattern that matches the Split-port manifold; from my calculations it also looks like the 14# injectors are close to being maxed out in the original non-Split-port application.
  • There are 2 adapters on the market -- hard plastic adapters or more homemade looking ones with exposed wires between the connectors. If you have the budget for buying adapters vs making your own, you might as well go with the hard plastic adapters. After all, you can always make your own adapters by splicing the fuel injector plugs from the Split-port harness to the car’s existing harness if you are encountering budget limitations.
  • I bought the following (8pack) set of Jetronic to USCAR adapters (Ford Racing Part# M-14464-A8) from buyfordracing.com.
  • Make sure you confirm that the adapters work for your chosen style of injector and harness (you don’t want to get adapters for the exact opposite of your application).
  • Finally, In order to run 19# injectors in a car that originally shipped with 14# injectors, you will need to do an ECU reflash. I explained what I needed and Don @ Lasota racing was willing to burn me an SCT chip to match my needs and maximize the value for this Split-port upgrade.
  • NOTE: This project will work with the stock ECU and stock 14# injectors from your old intake – you just won’t get the full advantage of the Split-port swap. In case you decide to stick with the 14# injectors though , here's a word of warning about the SK "injector rebuild" kit model SK57 -- the included pintle caps have the wrong sized opening. From what I can tell, they work with the 30# injectors that come with early SuperCoupes. I rebuilt my 14# injectors to use with my spare engine block and in doing so I needed to reuse my old pintle caps.

  • 2001 Mustang Throttle Body, TPS, and IACV
  • The Split-port throttle body is a different shape
  • The Split-port TPS is mounted in a different orientation and has a different sensor. You need a TPS sensor that opens from 0-5V in a clockwise fashion (Windstar is CCW. You may also find yourself building an adapter place if the mounting holes are 90degrees offset (I did).
  • The Split-port IACV mounts to the throttle body and not the intake manifold and has a different connector

  • Split-port compatible Return Style Fuel Rail
  • Original Tbird Fuel Rail: donates the Fuel Pressure Regulator (FPR) assembly
  • 1 or 2 Splitport Fuel Rails. Going with two costs slightly more but saves you potential points of failure (see details below)
  • Fuel Rail Buying Tip: when purchasing the fuel rail second hand from the internet, make sure to confirm if the seller will send you the fuel pressure sensor (FPS). Even if you won’t be using the FPS to regulate the fuel pressure in the system, you need the FPS to plug the hole in the fuel rail. Since I wanted to minimize the DIY points of failure in my fuel rail system, I had to go searching onto the internet for a replacement FPS for the one that the supplier of my second rail didn’t send to me.
  • SpringLock to Barb Adapters: There are multiple ways to solve this Problem. I actually tackled it twice. In my final iteration (after I realized that outside of injectors and the ECU the fueling system is a budget exempt category in Lemons), I purchased the following:
    - Ron Morris Performance Female Supply Springlock to Barb Adapter RM9141
    - Ron Morris Performance Female Return Springlock to Barb Adapter RM9142
    - (2) splitport compatible returnless fuel rails
  • You will need good quality, SS hose clamps. I found that #4 SS clamps are available for ~$2 in “10pc contractor packs” from Lowes.
  • Fuel Hose:
  • You also need J30R9 fuel injection hose (vailable in bulk from Autozone). J30R7 hose is significantly cheaper and more readily available but is NOT rated for the pressures found in FI systems.
  • Alternative: the “proper” hose recommended in other DIYs is to use Aeroquip FC332 socketless hose and fittings. That stuff is spendy so to keep with the spirit of the “24 Hours of Lemons”, I went with the J30R9 hose.
  • Cost Saving DIY Alternative #1: Build your own Springlock to Barb Adapters
  • Supply Line Springlock
    - Female Springlock Connector from original fuel rail
    - Steel Tube Nut model BLF-15C-5 from Autozone (sold in 5 pack): 3/8” Tube size, 5/8”-18 inverted thread size
    - Female 3/8” Flare to 3/8” male Barb coupling (Orchard Supply Hardware)
  • Return Springlock to Barb Adapter
    - Female Springlock Connector from original fuel rail
    - Steel Tube Nut model BLF-14C-5 from Autozone (sold in 5 pack): 5/16" Tube Size, 1/2-20 inverted thread size
    - Female 3/8” Flare to 3/8” male Barb coupling (Orchard Supply Hardware)
  • Cost Saving DIY Alternative #2: acquire one from a First Gen Ford Ranger
    - A friend and fellow TCCOAer (jco1385) who followed my splitport build reported that you can find the very same return springlock to barb fitting I purchased from Ron Morris on a First Gen (89-92) aka "square body" 4cyl Ford Ranger
    - You can easily cut this fitting off with some heavy duty snips and you can find it on the driver's side underneath the intake pipe towards the rear
    - A 2nd gen Ford Ranger or one of the V6 first gens might have a similar fitting but I don't have confirmation of this so please go to the junkyard and if you find one, let me know and I'll update this DIY.

  • Triple 3/8” male Barb Tee (ACE Hardware)
  • See Fuel System Modifications Section for more details

  • 2001 Mustang V6 throttle cable / accelerator cable
  • This one threw me for a loop as I didn’t see it mentioned in other Split-port threads/DIYs.
  • The end connector (how the accelerator cable physically attaches to the throttle body) is different) between my tbird and the mustang’s throttle body.
  • The V6 mustang’s cable is also 36” and the tbird’s was 40”. A new one is only ~$30 if you look but please note that for my 2001 intake manifold and throttle body, I needed a cable specifically for a 2001-2004 V6 mustang.
  • The mounting bracket is also different. I also had to purchase one for a 01 Mustang (came with my second fuel rail).

  • 2001 Mustang Upper and Lower Intake Manifold Gaskets

  • 2001 Mustang Thermostat Housing, 2001 Mustang upper radiator hose, and 2001 Mustang thermostat gasket.
  • I was originally hoping to re-use the 95 tbird’s original upper radiator hose and thermostat housing because I had modified the upper radiator hose to allow for additional coolant injection under pressure (a lemony way to keep your car on the track with minimal pitstops if it starts consuming coolant). However, the original thermostat housing hits the coolant pipe that wraps around the intake manifold and the original molded cable won’t reach the 2001 Mustang’s thermostat housing.
  • There are TWO upper radiator hoses at Autozone that will work for this application (Dayco #E72077 and Dayco #D71909). You want to go with the Dayco #D71909 hose as it places the radiator hose just a tad farther away from the tensioner pulley. After a few hours of driving, i found a groove in my E72077 hose that would have cause more serious problems on the track.
  • Your old thermostat is reusable here but I found the thermostat gaskets to be a slightly different shape.

  • O-rings for coolant hard pipes: I found two cooling pipe related o-rings that merit replacing:
  • One was for the hard pipe that goes into the top of the waterpump. My waterpump actually came with the necessary o-ring.
  • The second one is for the smaller hard coolant pipe that attaches to the back of the lower intake manifold. I found a compatible o-ring at Lowes in the plumbing section as the only ones Autozone carried with the necessary inner diameter were too thick. 1/2" ID, 5/8" OD, Size #28, comes in a 2-pack: http://www.lowes.com/pd_174733-72906-SC0529_0__?Ntt=174733&productId=3137361&rpp=16

  • Optional: Bypass the heater core with a 180 degree U-shaped tube to connect them. NOTE: one of the coolant tube openings is slightly larger than the other one. Dayco Part# B87629


  • 1995 Thunderbird Intake Tube - modified
    - More details below in the Re-Assembly Section

  • 2001 Mustang Head Gasket Set
    - Fel-Pro multi layer steel gaskets were recommended.
    - Copper gaskets are apparently available but I didn’t explore this further as they are a) way outside the 24 Hours of Lemons budget and b) require decking of the engine block.

  • 1995 Ford Thunderbird Head Bolts
  • Buy the head studs/bolts that match your engine block – not the Split-port heads
  • After 96, there was a change that was made that make the long studs just a little too short. I confirmed this by testing the length that the old head bolts protruded both the Split-port heads and the old heads while on my workbench. They were the same so therefore any change that merits a difference in headbolt length would need to be in the block.
  • Alternative: Head studs
  • Head Studs are available from ARP directly that work for 95 and older blocks.
    - 153-4203 (12pt nuts)
    - 153-4001 (6pt nuts)
  • For 95 and older blocks, you can also buy the head studs for a "Chevy 2.8L V6" and save some money. They are identical and cheaper.
    - 233-4303 (12pt nuts -- Chevy 2.8L V6 application)
    - 233-4003 (6pt nuts -- Chevy 2.8L V6 application)
  • For 96 and newer 3.8L engines, Tom @ maronav6racing.com commissioned ARP to make the right studs but they are pricey ($230+ when I last looked)
  • My thread on this subject: http://3.7mustang.com/vb/f5/q-about-3-8l-head-bolts-studs-95-tbird-block-01-mustang-heads-266472/
  • My Decision: Given the price, I just went with FelPro Head Bolts: FEL-PRO Part # ES72131 (for 94-95 mustang and 89-95 tbird)
 
Fuel System Modifications
IMO, the trickiest part of this whole project was converting the Split-port fuel rail from a return- less to return-style fuel rail to match the car's existing fueling system.

Returnless vs. Return Style Explanation:

  • The 95 tbird uses a completely mechanic return style fuel system - the fuel pump pressurizes the fuel rail and should the fuel pressure exceed a fixed level, the excess fuel dribbles down the return line.
  • The return-less systems require that when the pressure exceeds a certain level, the fuel pressure sensor tells the ECU to temporarily shut off the fuel pump.

While I thought this would be fairly straightforward to cut up my 95 tbird fuel rail and 2001 mustang Split-port fuel rail to make a Split-port rail that will work with a return-style vehicle, we encountered several issues with fitment. We did complete this build and then after realizing that the fueling system was a budget exempt item in Lemons (outside of the ECU, injectors, and I believe the fuel pump), we decided to redo it to minimize the number of DIY connection points by purchasing a second splitport fuel rail.
  • Issue 1: If you try and mount the Split-port rail in its stock orientation, you will find that the fuel rail will hit the distributor cap. The rail's position is set by the injectors and it's simply too far forward on the passenger side. You may think that you can cut the distributor cap plastic a bit and make enough room for the rail and then insulate the rail. DON'T DO IT. We tried this approach and the net result was that you have to trim so much plastic off the distributor cap that it is severely compromised (it's a good thing we were experimenting with an old cap).
    Solution: The solution is to run the fuel rail backwards (i.e.: the passenger side fuel rail goes on the driver side and the driver's side fuel rail gets used on the passenger side).
  • Issue 2: You won't actually notice this problem until after you start putting things together in more detail but I believe it merits explanation while you are still building your rail. When you turn the Split-port rail 180 degrees from "stock" position, the mounting holes will no longer be aligned.
    Solution: You just need one bolt per side so it will be obvious that you will need the modify the "forward" mounting tab on the passenger side and the "rear" mounting tab on the driver side. I ended up having to drill a second small hole above and to the right of the original hole and then enlarging it so that you end up with one odd shaped opening.
  • Issue 3: Two of the fuel rail mounting tabs will be "floating" in the air as they are no longer near their upper intake manifold assembly mount points when you flip the rail. The problem is that the forward driver side mounting tab will actually block your ability to plug the connector into the coolant temp sensor (esp if you use the factory hole for your ECT temp sensor -- a bigger 2 pin plug).
    Solution: Cut it off.
  • Underlying Concern: If you follow the flow of fuel in the original fuel rail, you will notice that the fuel pressure regulator (FPR) and therefore the fuel return connection is placed downstream of all the fuel injectors. This also means that the pressure between the two rails should be balanced. Therefore, the injectors see the full fuel pressure the pump can provide and the FPR will send fuel back down the return line only if the remaining pressure at the end of both rails is above the target (I believe 39 or 40 PSI).

    Solution:
  • Make sure the fuel follows the same flow down the splitport rails as it does with the singleport return-style system. Put together the fuel rail so it flows in the following pattern: factory springlock => brazed & JB welded springlock to BARB adapter => 3-way Barb Tee => down both fuel rails => both fuel rails then go into the FPR => brazed & JB welded springlock to BARB adapter => factory springlock return.
    spfuelrail_diagram.jpg



  • Install the fuel injectors (rebuild them first if you feel like it) into the lower intake manifold.
  • We started with two splitport fuel rails. Separate them according to the suggestions below and you will end up with (2) fuel rails sections with barbs at each end and a fuel pressure sensor+schrader valve at one end and (2) fuel rails with a barb at one end and a supply springlock + barb at the other end. The goal is to keep the (2) fuel rail sections w/ barbs at each end. In other words, if you are cutting up 2 fuel rails keep the two driver's side segments.

    - See this DIY for suggestions on how to remove the factory hose covering without damaging the existing barbs. http://www.tccoa.com/articles/mn12how-to/fuel-rail/fuel-rail.html
    - I also found another thread that recommended using a wire brush on a drill/grinder to abrade off the inner plastic hose without damaging the barbs. http://www.fordmuscleforums.com/induction-articles/496428-ford-fuel-rail-rehab.html
    03b.jpg


    03c.jpg


  • You will then use the two rails with just barbs at the ends for your car and keep the others as spares.

  • Separate the FPR from the original return-style fuel rail at the barb points using the same techniques as applied to the splitport rails above. This will leave you with a FPR mounted to an assembly with a metal bracket at the bottom and 3 barbs sticking out of the sides.


  • Cost Saving Option: While I used the commercially manufactured female springlock to male barb adapters purchased from Ron Morris Performance, you can also fabricate your own springlock to Male Barb adapters. I decided that although it pained me to spend ~$40 shipped for two small metal adapters, it was better than dealing with a burned out engine bay in a vehicle I've literally put 500+ hours in prepping.
  • I did this by cutting off each springlock as close to the rail as possible.
  • I then slid the tube nut over the springlock stub and flared the end with a flare tool borrowed from Autozone.
  • JB weld was used on the male threads and the barb adapter was screwed onto the tube nut and allowed to cure.
  • I then used silver solder to braize at the joint between the tube nut and the barb connector.
  • Finally, I covered the joint with another layer of JB Weld (temperature and gasoline resistant).
    04a.jpg


    04b.jpg


    04e.jpg



  • Another Cost Saving Option: You can also get away with buying only one splitport fuel rail. In this scenario, you will need to either a) block off the female springlock adapter or cut the whole barb+springlock end off entirely and attach a female flare to Barb adapter at that end using the techniques described above on how to make your own springlock adapters. Note: This modified rail will need to go on the driver’s side of the engine as in its stock position (on the passenger side), this rail will hit the distributor cap.
    04c.jpg


  • Cheapest Option: Of course, you COULD just shove the hose over the cut off end of the springlock stubs and clamp it down but that didn’t sit well with me safety-wise. 32PSI of gasoline spraying on top (vs inside) my hot engine block doesn't sound like a good idea to me.

  • SPECIAL NOTE: Double clamp everything!!

    Other Alternative Solutions for the Overall Fuel System:
  • Switch your ignition system from a distributor to a distributor-less system. This would require a re-pinning of the engine harness and a new ECU reflash.
  • Purchase a fuel rail from a 2000 E150 van as a starting point. Allegedly, you can spin it around and use a torch to bend up the corner of the rail that comes into contact with the distributor. You will also need to extend the stock fueling/return lines with a fuel line extender kit. Considering the relative rarity of an E150 V6 fuel rail and its corresponding price, I opted to just modify the Split-port rail I already owned.
  • Yet another alternative is to buy a 95-98 F150 V6 fuel rail. The F150 V6 fuel rail supports split-port heads AND has a return fuel line. The catch is that you apparently need a VAP Auto phenolic intake manifold spacer to make it fit. You will also run into underhood clearance issues here. Given the rarity of F150 V6 fuel rails and the additional cost of a phenolic spacer (~$100), I disregarded this option as well.
  • A final alternative to my chosen method is that apparently you can switch from return-style to returnless functionlity via an ECU reflash and harness wiring. I didn't explore this option any further due to the requirement to modify the engine harness.
 
Fuel System Modifications
IMO, the trickiest part of this whole project was converting the Split-port fuel rail from a return- less to return-style fuel rail to match the car's existing fueling system.

Returnless vs. Return Style Explanation:

  • The 95 tbird uses a completely mechanic return style fuel system - the fuel pump pressurizes the fuel rail and should the fuel pressure exceed a fixed level, the excess fuel dribbles down the return line.
  • The return-less systems require that when the pressure exceeds a certain level, the fuel pressure sensor tells the ECU to temporarily shut off the fuel pump.

While I thought this would be fairly straightforward to cut up my 95 tbird fuel rail and 2001 mustang Split-port fuel rail to make a Split-port rail that will work with a return-style vehicle, we encountered several issues with fitment. We did complete this build and then after realizing that the fueling system was a budget exempt item in Lemons (outside of the ECU, injectors, and I believe the fuel pump), we decided to redo it to minimize the number of DIY connection points by purchasing a second splitport fuel rail.
  • Issue 1: If you try and mount the Split-port rail in its stock orientation, you will find that the fuel rail will hit the distributor cap. The rail's position is set by the injectors and it's simply too far forward on the passenger side. You may think that you can cut the distributor cap plastic a bit and make enough room for the rail and then insulate the rail. DON'T DO IT. We tried this approach and the net result was that you have to trim so much plastic off the distributor cap that it is severely compromised (it's a good thing we were experimenting with an old cap).
    Solution: The solution is to run the fuel rail backwards (i.e.: the passenger side fuel rail goes on the driver side and the driver's side fuel rail gets used on the passenger side).
  • Issue 2: You won't actually notice this problem until after you start putting things together in more detail but I believe it merits explanation while you are still building your rail. When you turn the Split-port rail 180 degrees from "stock" position, the mounting holes will no longer be aligned.
    Solution: You just need one bolt per side so it will be obvious that you will need the modify the "forward" mounting tab on the passenger side and the "rear" mounting tab on the driver side. I ended up having to drill a second small hole above and to the right of the original hole and then enlarging it so that you end up with one odd shaped opening.
  • Issue 3: Two of the fuel rail mounting tabs will be "floating" in the air as they are no longer near their upper intake manifold assembly mount points when you flip the rail. The problem is that the forward driver side mounting tab will actually block your ability to plug the connector into the coolant temp sensor (esp if you use the factory hole for your ECT temp sensor -- a bigger 2 pin plug).
    Solution: Cut it off.
  • Underlying Concern: If you follow the flow of fuel in the original fuel rail, you will notice that the fuel pressure regulator (FPR) and therefore the fuel return connection is placed downstream of all the fuel injectors. This also means that the pressure between the two rails should be balanced. Therefore, the injectors see the full fuel pressure the pump can provide and the FPR will send fuel back down the return line only if the remaining pressure at the end of both rails is above the target (I believe 39 or 40 PSI).

    Solution:
  • Make sure the fuel follows the same flow down the splitport rails as it does with the singleport return-style system. Put together the fuel rail so it flows in the following pattern: factory springlock => brazed & JB welded springlock to BARB adapter => 3-way Barb Tee => down both fuel rails => both fuel rails then go into the FPR => brazed & JB welded springlock to BARB adapter => factory springlock return.
    spfuelrail_diagram.jpg



  • Install the fuel injectors (rebuild them first if you feel like it) into the lower intake manifold.
  • We started with two splitport fuel rails. Separate them according to the suggestions below and you will end up with (2) fuel rails sections with barbs at each end and a fuel pressure sensor+schrader valve at one end and (2) fuel rails with a barb at one end and a supply springlock + barb at the other end. The goal is to keep the (2) fuel rail sections w/ barbs at each end. In other words, if you are cutting up 2 fuel rails keep the two driver's side segments.

    - See this DIY for suggestions on how to remove the factory hose covering without damaging the existing barbs. http://www.tccoa.com/articles/mn12how-to/fuel-rail/fuel-rail.html
    - I also found another thread that recommended using a wire brush on a drill/grinder to abrade off the inner plastic hose without damaging the barbs. http://www.fordmuscleforums.com/induction-articles/496428-ford-fuel-rail-rehab.html
    03b.jpg


    03c.jpg


  • You will then use the two rails with just barbs at the ends for your car and keep the others as spares.

  • Separate the FPR from the original return-style fuel rail at the barb points using the same techniques as applied to the splitport rails above. This will leave you with a FPR mounted to an assembly with a metal bracket at the bottom and 3 barbs sticking out of the sides.


  • Cost Saving Option: While I used the commercially manufactured female springlock to male barb adapters purchased from Ron Morris Performance, you can also fabricate your own springlock to Male Barb adapters. I decided that although it pained me to spend ~$40 shipped for two small metal adapters, it was better than dealing with a burned out engine bay in a vehicle I've literally put 500+ hours in prepping.
  • I did this by cutting off each springlock as close to the rail as possible.
  • I then slid the tube nut over the springlock stub and flared the end with a flare tool borrowed from Autozone.
  • JB weld was used on the male threads and the barb adapter was screwed onto the tube nut and allowed to cure.
  • I then used silver solder to braize at the joint between the tube nut and the barb connector.
  • Finally, I covered the joint with another layer of JB Weld (temperature and gasoline resistant).
    04a.jpg


    04b.jpg


    04e.jpg



  • Another Cost Saving Option: You can also get away with buying only one splitport fuel rail. In this scenario, you will need to either a) block off the female springlock adapter or cut the whole barb+springlock end off entirely and attach a female flare to Barb adapter at that end using the techniques described above on how to make your own springlock adapters. Note: This modified rail will need to go on the driver’s side of the engine as in its stock position (on the passenger side), this rail will hit the distributor cap.
    04c.jpg


  • Cheapest Option: Of course, you COULD just shove the hose over the cut off end of the springlock stubs and clamp it down but that didn’t sit well with me safety-wise. 32PSI of gasoline spraying on top (vs inside) my hot engine block doesn't sound like a good idea to me.

  • SPECIAL NOTE: Double clamp everything!!

    Other Alternative Solutions for the Overall Fuel System:
  • Switch your ignition system from a distributor to a distributor-less system. This would require a re-pinning of the engine harness and a new ECU reflash.
  • Purchase a fuel rail from a 2000 E150 van as a starting point. Allegedly, you can spin it around and use a torch to bend up the corner of the rail that comes into contact with the distributor. You will also need to extend the stock fueling/return lines with a fuel line extender kit. Considering the relative rarity of an E150 V6 fuel rail and its corresponding price, I opted to just modify the Split-port rail I already owned.
  • Yet another alternative is to buy a 95-98 F150 V6 fuel rail. The F150 V6 fuel rail supports split-port heads AND has a return fuel line. The catch is that you apparently need a VAP Auto phenolic intake manifold spacer to make it fit. You will also run into underhood clearance issues here. Given the rarity of F150 V6 fuel rails and the additional cost of a phenolic spacer (~$100), I disregarded this option as well.
  • A final alternative to my chosen method is that apparently you can switch from return-style to returnless functionlity via an ECU reflash and harness wiring. I didn't explore this option any further due to the requirement to modify the engine harness.
 
Windstar Upper Intake Manifold Addendum

Q: Why upgrade bother with a windstar upper intake manifold vs. the mustang splitport upper intake?
A: 15HP. It's also a composite plastic so it weighs significantly less than the Mustang intake.

Q: What's the biggest disadvantage?
A: You will need to modify your hood for clearance.

This DIY Addendum to my Splitport Swap DIY assumes you already have a splitport setup on your 3.8L engine. This is also a documentation of the choices I personally made in this upgrade. There are all sorts of different combinations for installing a Windstar intake and they all depend on what concerns/concessions you are willing to make.

My car is used in 24 Hours of Lemons racing so I’m extremely budget constrained (hence the scrap metal for the bracket). I also have no qualms about punching holes in my hood for extra clearance whereas other folks might be willing to buy spacers to angle their throttle bodies and gain just that little extra bit of clearance. With 3 months until my next race and since snowboarding season hasn't started yet, I couldn't leave this engine alone so I decided to tackle this project.

Research
BEST DIY is in this Word Doc - http://www.allfordmustangs.com/foru...ake-swap-questions-look-here.html#post1472143

Yet Another DIY - http://www.moddedmustangs.com/forum...na-2002-v6-build-pic-heavy-3.html#post4697205

Yet Another DIY - http://www.v6power.net/vb/showthread.php?t=34692

Questions - http://www.allfordmustangs.com/forums/v6-tech/166720-windstar-intake-swap-questions-look-here.html

VAPAUTO's discontinued $450 kit - http://www.vapauto.com/windstar.htm

Items Needed/Basic Steps:
  • Mount Windstar Upper Intake: don’t lose any of the plastic standoffs or you may find yourself going back to the junkyard like me. You will likely need to rearrange bits on the front of your engine because things will get more crowded (see below).
  • Modify the fuel rail (if needed) and/or fabricate brackets to mount fuel related items (like your fuel pressure regulator)
  • Throttle Body (see below)
  • IACV and possible relocation (depending on TB choice and clearance preference).
  • Fabricate throttle cable adapter bracket
  • Extend IACV and Throttle position sensor electrical connectors
  • Extend vacuum lines/cap off unneeded vacuum ports
  • Install intake tube/MAF/airbox elements.
  • Cut hood/fabricate cowl hood.
Challenge - Throttle Body, TPS, & IACV
Based on my research, what throttle bodies you choose to install end up informing the other choices you make on IACV placement. On the Windstar throttle body, there’s an air channel built into the throttle body from just before the throttle plate that goes into the top of the windstar intake for the IACV. Depending on what TB you chose, you may have to block off this air passage and relocate the IACV or use it.

Options:
  • Windstar throttle body – will (obviously) bolt onto the windstar intake but the throttle body itself is actuated in a counter clockwise fashion whereas on my application (tbird), the throttle body needs to be actuated in a clockwise manner.
  • Mustang GT Throttle body – will bolt onto the intake but does not have an allowance for the IACV port in the TB. Therefore, you will need to:
  • Block off/fill in the IACV port on the windstar upper intake.
  • Create a plate/mount bracket for the IACV and run two hoses – one to the intake tube (between the MAF and the throttle plate) and a second into the intake manifold.
  • This bracket can also be purchased from vapauto.com
  • Mustang V6 throttle body – this one will physically bolt up to the windstar intake manifold, is actuated in the proper fashion clockwise, AND has an IACV air channel above the throttle plate. The problem with this throttle body is that the IACV air channel itself is ¼” too low. Why? Presumably for hood clearance reasons. The solution here is to fabricate an adapter plate like StalkerStang on Allfordmustangs.com. Since I lack a machine shop with milling capabilities, I skipped this option
    100_2273.jpg


  • CHOSEN SOLUTION: My chosen solution to this problem was driven by my lack of machining capabilities and possession of both a Mustang V6 throttle body and a Windstar throttle body. Using the “Best DIY” word doc as a guide, I swapped the internals (throttle cable mounting bracket, spindle, and throttle plate) from the mustang throttle body into the Windstar throttle body.
  • TIP for removal of the throttle plate: soak the screws in PB Blaster. Put a screwdriver on the threads and hit it with a hammer to disrupt any crud in the threads. Finally, I used a crescent wrench around the screwdriver to generate additional torque to remove the treads. Try not to strip the heads of the screws!
  • This also required a little bit of grinding on the Windstar intake to insure smooth operation.
  • The net result was a working throttle body that actuated clockwise AND uses the IACV mounted in the stock location (up top).
  • Updated Tip: Throttle Position Sensor: you will also need to swap TPS sensors with the one from a Mustang or Tbird. This is because the Windstar's TPS is designed to increase from 0-5V in a counter-clock direction and on the tbird, you need it to open clockwise.
  • In my situation, I needed to fabricate an adapter plate because my chosen TPS (came from a late 90s mustang or F150) had its mounting holes mounted exactly 90 degrees from the threaded holes in my Windstar's throttle body. If you don't setup the TPS correctly and the ECU doesn't get near the full 5V at WOT, it will never switch to the WOT fuel map. That's no fun. See pic. For reference, the attachment points on the Windstar TB are #10-32 thread (found at Ace Hardware)
  • SUGGESTION: If you are trying to keep the stock hood, you will need to cut down the IACV mount point, fill it in, relocate the IACV, and tilt the TB downwards so that its upper arm won’t hit your hood. Vapauto.com sells a tilted throttle body spacer but from what I can tell, it's only for the Windstar throttle body shell. See “Best DIY” for more details.
Challenge - Throttle Cable Bracket:
There are lots of examples of how folks made these brackets. My solution was pretty simple. I used two pieces of scrap metal (one rectangular 1/8” flat stock) and one piece of angle iron (from a bed frame I passed by on the street in SF a while ago and promptly cut up) to create a mount point for the Mustang Throttle Cable Bracket. The flat stock is then drilled to use the IACV mount points AND can serve as a cap for these ports if you chose to remotely mount the IACV.
  • Pros: this design keeps the same geometry as on the mustang splitport design (I measured things on the splitport setup before I removed it from my 3.8L engine) and therefore the same pedal pressure.
  • Cons: The downside of this design is that it’s a bit tall. Not a concern is you are going to cut up your hood anyway.
  • The dimensions of the pieces I made are as follows. These should get you close.
  • Flat Stock (3" x 4.5"): This mounts flush with the front of the windstar intake and has enough room to allow you to attach the angle stock while leaving room for all four IACV holes (2 mounting holes and the intake/output ports)
  • Angle Stock (6" long).
  • The key is to attach the angle stock so that when you attache the throttle cable bracket to it, the throttle cable will be lined up directly behind its attachment point on the TB. The mounting face of the throttle cable bracket (where the throttle cable clicks in) is 4.5" inches from the front of the flat stock piece AND 5" inches from the edge of the TB that mates to the upper intake manifold).
  • I measured these positions by taking a piece of wire and cutting it so that it would be the correct length of cable in front of the mounting face.
  • I welded the two metal pieces together after determining the right position. If you lack a welder, just drill two holes and bolt the pieces together.
  • There is adjustability in this design as you can move the throttle cable bracket forward and back by drilling additional holes in the angle stock. Test if your throttle body is opening up entirely by putting someone in the driver’s seat and have them depress the pedal while you look at the TB. If it opens up all the way, your distance between the face of the throttle cable bracket and the throttle body itself is correct.
Windstar Upper Intake Mounting
Even though the Windstar Intake is taller than the Mustang upper intake, curiously enough it is NOT necessarily easier to install as the intake is mounted more forward (towards the radiator) than the Mustang equivalent. I ended up having to move/reorganize several components at the front of my engine to make enough room for the throttle body and to allow the intake to rest flat.
  • Cooling System Top Vent: this required the most modification as you need to a) bend the hex-shaped tube forward (see “Best DIY”) and b) cut down both the hex shaped section AND the bolt itself for more clearance. Tips:
  • Do NOT cut the hex tube flush with the top-most cooling tube or you might not save enough threads to be useful. Err on the side of caution and leave yourself a little of the hex tube – you can always trim more later.
  • You may also find yourself needing to cut down the bolt that goes into the top of the hex-shaped tube.
  • Finally, I found that I needed to trim a “tiny amount” off the bottom of the windstar upper intake. The material removed was a small mount of the supporting material that braces the throttle body mount to the main portion of the windstar upper intake.
  • Fuel Pressure Regulator: I originally bolted mine to the rear of my Mustang Upper Intake. There is no equivalent bolt point in that area of the Windstar upper intake so I fabricated a bracket to bolt it securely onto the lower intake manifold.
  • Fuel Rails: According to the “Best DIY”, you will need to bend the fuel rail down at the front passenger corner. However, since my fuel rail is already flexible (it’s a return-style splitport rail now), this wasn’t a problem for me. I did find myself cutting off the connector of the fuel pressure sensors (used for the returnless fuel systems) on the front of the drivers side fuel rail though. This won’t be a problem even if I migrate to a returnless style system because there’s a second fuel pressure sensor on my passenger side rail.
  • Distributor Cap: curiously enough, this wasn’t a problem for me even though the Windstar uses a distributor-less ignition system like the Mustang. At worst, you will need to creatively move the ignition wires around but you will have room.
  • EGR: if you still have an EGR valve, you will need to move it to gain more clearance at the front of the engine. See the “Best DIY” for more details.
  • Oil Pressure Sensor: I have an aftermarket oil pressure sensor that I needed to move it over a bit to make room for the throttle body.
Concerns – Intake Tube Placement
Once you have the intake manifold mounted, the final mechanical issue to solve is the mounting of the intake tube.
  • The easiest option is to buy the necessary intake tube materials to draw the air from near the stock airbox location and replace the airbox with a cone filter.
  • Besides looking a bit “cheaty” for lemons, I also didn’t want to go out and buy anything else.
  • My decision was to re-mount the airbox at an offset angle that would place the MAF in a position reachable by the stock singleport intake tube (the cut down intake tube I used with the mustang conversion is now just slightly too short).
  • Take the upper radiator hose spec'd in the parts section and trim a approximately 1" from the radiator end. This will make the 90 degree bend a bit less kinked.
  • I then fabricated brackets to hold the airbox securely in position and fabricated a small heat shield so that when the air gets drawn in – mostly from the hole in the fenderwell but also from the engine bay now because the bottom of the airbox is no longer flush with the hole in the fenderwell.
  • My first revision was to design a metal strap to prevent the upper radiator hose from hitting the accessory belt. As it turns out, its the idler pulley that you need to watch out for so I updated my setup with a metal bracket that goes from the radiator cross brace to a tab on the distributor housing
  • The downside of my design is that it causes the airbox area to rise higher than the stock hoodline; I’m going to need to cut a bigger section of my hood for a cowl.
splitport_urh_brace1.jpg


splitport_urh_brace2.jpg



Other Concerns:
  • Vacuum lines: I needed to extend my fuel pressure regulator vacuum line and swap valve cover venting (the passenger side now goes into the intake tube and the driver’s side goes into the intake manifold now – it was opposite when I was using a Mustang upper intake). Also, don’t forget to cap the vacuum tube that’s underneath the IACV.
  • EGR: the EGR tube will conflict with the rest of the mess in front of the intake.
  • Check your timing! I finally found the heart of my engines inability to rev beyond 4k rpm recently. My spark-out jumper was missing so the ECU wasn't advancing timing AND base timing was set at 30 degrees. I fixed both and it feels like a different car now.
Next Steps:
  • DONE - Go racing!
windstar1.jpg


windstar2.jpg


windstar3.jpg


windstar4.jpg


windstar5.jpg
 
2023 Update: If I was to do this again (and I won't after swapping to a V8), I would start with a 4.2L V6 and rebuild the bottom end before adding 60% more HP. Even if you stick with a 3.8L crank/pistons, don't upgrade the heads without taking apart the bottom end first.

Also (lesson learned from tracking the V8) a cooling system capable of adequately cooling a 140HP engine isn't going to be happy with 250HP+ (V8 w/ GT40 heads and straight pipes). Upgrade, or plan to upgrade, accordingly.
 

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