Kooks EGR fitting

[XR7-4.6]

I was changing the only on my 97 E350 today. And because of this conversation I looked at the EGR tube. On my 5.4 it is much larger than the Tbird size Egr nut. Maybe you can get one from an old 5.4.

That’s good to know! I’m probably putting EGR back on eventually so having a readily available doner tube to source that end from would come in very handy

But problem solved, garden hose cap worked!(yes I took the rubber out lol)

 

[supergordo]

Well if you took the rubber out, at least if you get a head gasket failure on that side the water will leak out the cap!

 

[Grog6]

While we're talking about headers, what will
I trash if I use round headers on a 4v head?

 

[XR7-4.6]

While we're talking about headers, what will
I trash if I use round headers on a 4v head?

You’d be better off selling them and putting the proceeds toward the 4V kooks. Probably can fetch $600-$700 if they’re in good shape so it’s not terribly more expensive to get the right ones, that’s cheaper than trashing perfectly good ones lol

 

[Grog6]

That's way out of my budget. I guess I'll be building with my npi heads/pi cams.
I'm going to measure my crank today; the one from the red cougar was perfect, I just trashed its heads.
I doubt the crank in lazarus is reusable, with the rod knock and rod breakage. I'll use laz's heads,on my teksid block, with new pistons, the manley rods I got cheap, and the kooks .

 

[XR7-4.6]

That's way out of my budget. I guess I'll be building with my npi heads/pi cams.
I'm going to measure my crank today; the one from the red cougar was perfect, I just trashed its heads.
I doubt the crank in lazarus is reusable, with the rod knock and rod breakage. I'll use laz's heads,on my teksid block, with new pistons, the manley rods I got cheap, and the kooks .

That was the combo I was preparing to build before I got my DOHC. That with VT/Cushman cams and longtubes as I wanted would be a hot little 2V

 

[Grog6]

The crank from the red cougar, at 233kmi, measures as 0.0007 wear from stock, worst case.

 

[XR7-4.6]

The crank from the red cougar, at 233kmi, measures as 0.0007 wear from stock, worst case.

Yeah I wouldn’t worry about it lol

 

[Grog6]

Me either, my 390's were never that close. That's only0.0003 wear. The mark bores are only0.0005 wear, in 158kmi.

 

[XR7-4.6]

So I'll share my latest debacle; gaskets! I hate header gaskets! No matter what brand theres a million horror stories where they wind up leaking for one reason or another and I'm not going to want to revisit this install to fix them. Up until a few days ago I was intending to use the factory 03-04 DOHC gaskets which are MLS just like the headgaskets and those seal extremely reliably.... but here’s the kooks port



Here’s the cobra gasket



See the problem?

I’ll make it even more obvious, I scaled that image to my screen and traced the flange off my kooks



Yeah the port is too damn big to use it, essentially forcing my hand to go aftermarket

BUT There might be another MLS option, gaskets for 07-14 GT500 heads.



These have much larger exhaust ports, similar to the Kooks, but the caveat is that the bolt spacing is different than 4.6 heads, (because “Modular” lol), oh and these gaskets cost ~$40 each and you need 4 of them… but using my same tracing…



Pretty tantalizingly dead on match port wise, eh? There’s also plenty of dead space in the gaskets where I could slot the holes… decisions…decisions…

 

[KevinVarnes]

Have you looked into the Remflex gaskets? They are supposed to be pretty good. Can't comment on the port size/shape. Plus they are endorsed by Dulcich and Wiley!

 

[XR7-4.6]

Have you looked into the Remflex gaskets? They are supposed to be pretty good. Can't comment on the port size/shape. Plus they are endorsed by Dulcich and Wiley!

Yes but I just don’t trust thick gaskets like that, I see the purpose with cheap headers with thin warpy flanges but the kooks are beefy and true. Quite frankly if it weren’t for the mess I’d do copper RTV only, no gaskets at all, if anything.

Dulcich and Wiley isn’t a ringing endorsement to me

 

[MadMikeyL]

For what it’s worth, I used the remflex gaskets for the 393 in my f150, and they don’t leak, even after a few R&Is of the header. If they make one that will work, I would sooner go that route vs trying to cut up the GT500 ones.

 

[XR7-4.6]

For what it’s worth, I used the remflex gaskets for the 393 in my f150, and they don’t leak, even after a few R&Is of the header. If they make one that will work, I would sooner go that route vs trying to cut up the GT500 ones.

They do but unless they’ve changed (which it doesn’t look like) they have the smaller oval port shape of B heads/early C heads so there’s still potential they’d need to be slightly cut up anyway… in fact one would have to get cut up anyway because you can’t use a 1 piece gasket on the driver side with the factory dipstick tube.



I’m not completely ruling anything out yet, but it would be quick and easy to either slot the holes in the GT500 gaskets or reshape the ports in the remflex with my dremel. I’d certainly rather pay $40 over $140 too obviously but I literally never want to touch them again and feel there’s just more variable to allow for that possibly with a thick crush gasket. The OEMs are ludicrously expensive but they’re proven lifetime gaskets

Out of curiosity what do you torque these aftermarket gaskets to? Same as the factory spec or?

 

[MadMikeyL]

I just tightened them all as much as I could with the 1/4” ratchet, and then went over them again after it had heat cycled.

 

[XR7-4.6]

I just tightened them all as much as I could with the 1/4” ratchet, and then went over them again after it had heat cycled.

The latter is the big problem with a 4.6 in this engine compartment. Retightening them down after a heat cycle is simply not an option, I want one and done like it is with manifolds/factory gaskets which don’t need that additional step

 

[MadMikeyL]

Re-torquing after a heat cycle is a function of headers vs manifolds, regardless of what gaskets you use. The header flange will warp and move more than a cast iron manifold, requiring it to be retightened. MLS gaskets might be less prone to completely blowing out, but unless retorqued, headers are likely to leak.

 

[XR7-4.6]

Re-torquing after a heat cycle is a function of headers vs manifolds, regardless of what gaskets you use. The header flange will warp and move more than a cast iron manifold, requiring it to be retightened. MLS gaskets might be less prone to completely blowing out, but unless retorqued, headers are likely to leak.

But once again, it’s simply not possible to retorque after a heat cycle unless you pull the motor/drop the K member again with headers in a 4.6 MN12. There are a few bolts you can get at with a combination wrench assembled but not most.

I’d also argue the kooks flange is beef, much more so compared to the 4V MACs I have which are pretty typical of most header flanges I see. I think there’s more to it than the simple composition of cast iron vs steel.

 

[MadMikeyL]

So fire it up and run it up to temp a few times before you bolt the subframe back in place. They’re headers. You are going to have to retorque them. The only question is are you going to do it now, or are you going to do it later, along with new gaskets because it has been leaking and burned them up. After they have been on the car and heat cycled a bunch of times, then maybe you can get away with not having to retorque them, but a brand new set of headers, they are going to move as it heats and cools. A thicker flange is great, but it will never be as straight and smooth as a machined cast iron surface.

 

[XR7-4.6]

Is that what kooks headers users in MN12s/FN10s do? Because I feel like that’s something I probably would have remembered through the years Having the engine on a support bar and jack under the oil pan with the K member is sketchy enough, actually running the engine (a shakey cammed one at that) on it isn’t particularly appealing, not to mention the support bar I have doesn’t even fit with the upper intake manifold attached so it wouldn’t run anyway.

 

[MadMikeyL]

If you’re worried about running it on the hoist, then just zip the subframe back in place with a couple bolts and let it sit on the subframe. Or you can crank down on them and hope for the best, but I wouldn’t count on it not leaking in a few months.

 

[dDUBb]

I never re-torqued my header bolts when I did the JBAs ( this was 1998 ) .. matter of fact .. I didn't even use a torque wrench.

 

[XR7-4.6]

If you’re worried about running it on the hoist, then just zip the subframe back in place with a couple bolts and let it sit on the subframe. Or you can crank down on them and hope for the best, but I wouldn’t count on it not leaking in a few months.

Oh so do the hardest part twice lol

See for me this boils down to gaskets, not all factory manifolds are cast iron, in fact stock Coyotes use essentially factory shorty headers… do they have a post heat cycle retorquing procedure in their service manuals? (I don’t know but I’m certainly curious about it). To me there are good headers and crappy headers (like my pictured MACs) the latter benefits from thick flexible gaskets like remflex because they have a thin flange that was probably warped from the day they were welded, and these gaskets by their composition and nature of being flexible will allow for additional expansion allowing for leakage if not retorqued.

Maybe I am just being stubborn (and forgive me if it seems like I’m trying to fight you about this) but I think this has a lot more to do with the notoriety of header leaks than the header material composition itself. Most headers NEED gaskets of the nature of remflex and others with lots of give(adaptability to imperfect flanges) to compensate for warpage, which need retorquing, but I just simply question whether these Kooks headers fall into the category of it. I checked the flanges and they are laser straight, why would they need a gasket any different than the stock style multilayered steel gasket that came stock on a similar head with a similar welded manifold/header? And once again what lengths do others with 4.6 kooks headers go through to make them seal? I have never once heard one single mention from anybody who has them about retorquing them after a heat cycle, and given the involvement of doing such a job you’d think would be as bitchworthy as the steering rack or heater core even the most hardened of us whine about.

 

[dDUBb]

Thermal expansion coefficient .. just like your brass hose cap.

Re torquing the header bolts is bolt conditioning. Tightening them to spec in sequence after they've been stretched a couple times.

 

[MadMikeyL]

Well I can’t speak for the mn12 kooks mid lengths in particular as I’ve never installed a set of them, but I have installed many headers at price ranges from $100-$2000, and it has always been my procedure to retighten them after a heat cycle or two, and not one time have I found all the bolts still tight, regardless of what brand header, or how thick the flange, or what type of gasket was used. Loose bolts lead to blown out gaskets, and that means having to unbolt the header completely to change them, vs just lowering the K-member to hit each bolt one more time. I get that it’s daunting, and it sucks, but so does installing and degreeing 4 cams in the engine bay, and you didn’t have a problem with that.

 

[Zep5.0]

I mean, I'm seeing Mikey give you a reason to run open headers with cams a couple times.. I bet the sounds will make it worth the hassle.

Oh, and my 1 3/4" Hookers suck to tighten out off the car. I'm sure they will suck more when I tighten them after a couple heat cycles, too. It's the price of cool and fast

 

[97 30th]

I checked the bolts I could get at on my kooks after running it and didn't find one that was loose. I used MLS gaskets and tightened them pretty good to begin with because I knew I wouldn't be able to get at all of them once in the car.

 

[XR7-4.6]

I mean, I'm seeing Mikey give you a reason to run open headers with cams a couple times.. I bet the sounds will make it worth the hassle.

But I was already going to do that without a labor intensive excuse


Alright guys point well taken, I knew exactly what I was getting into with headers (and why I avoided headers for years) so I’m just venting. I’m still undecided on gaskets though, hardware I’m now leaning more towards reuse the factory studs(where they fit at least) instead of locking bolts that seem like way more trouble than their worth… especially with the prospect of retorquing.

 

[MadMikeyL]

I tried the locking header bolts one time, they were totally not worth the aggravation. I think there were multiple bolts where I couldn’t even get the locking tabs on, and then after re-torquing them the tabs were no longer against the header tube, so they weren’t even doing anything. If the factory studs will work, that is the best option, at least for 2 bolts on each side so it will help line everything up.

 

[KevinVarnes]

Remflex says 20 ft-lbs for the gaskets. And this:

No Re-Torquing Necessary:

Remflex exhaust gaskets rebound 30%, creating an optimum seal that eliminates the need to re-torque!