The Unofficial "Ask a Stupid Question" Thread

Another question:

Has anyone ever used a Mustang PCM in their MN12?
I'd be curious if the Mustang (stock) tune feels any different.

In the case of the V6, I think the Mustang has a longer final drive (2.73?), so it might compensate for that with later upshifts (?). Or would the PCM misinterpret my actual speed if I used a Mustang PCM with my final drive (3.08?; 3.23?).

Just curious if anyone has any experience just swapping PCMs. I mean Mustangs are reasonably plentiful in junkyards; I might be tempted to try it out.
 
I don’t know of anyone using a Mustang ECM on a V6 car, but I know people have done it on the V8 cars. As for the final drive ratio, it shouldn’t really make much of a difference since both cars use a gear-driven speed sensor, so the car will still know how fast it is going. The actual shift points might change slightly, but those are calculated based on acceleration rates, so while the Mustang has shallower gears, it is also about 400lbs lighter, so it might even cause lower shift points.
 
One problem with a PCM swap is if the MAF is different between MN12 and Mustang the transfer function will be off.

I wouldn’t expect much if any change any more than switching from one catch code MN12 PCM to a different one would. Ford didn’t tune Mustangs shifts any more aggressively
 
1997ThunderbirdLXV6 said:
And would you install a temperature sensor, or pull a signal from the existing sensor?
Click to expand...
I installed a temperature sensor in place of the one for the dash. I tried to do both, and it didn’t work for me. I prefer my Autometer gauge over the stock one anyhow, it’s much more accurate.
 
I have my mechanic trying to put on Mark VIII rear LCAs onto my 97 Bird right now and they just called and said it was impossible: they don't fit. Now, obviously they can be made to work because tons of people have done this mod and I have pictures of them on Thunderbirds. So, does anyone have any idea what they're missing that's making it look like this is a swap that can't be done onto a 97 Bird?

EDIT: They sent me a picture to show how they're not the same, and this is the reason why they can't do the swap. I'm not sure what the photo really tells though, other than "they're not exactly the same". Am I or they missing something? They have the necessary Mark VIII bolts. I'd appreciate any quick help here, since this might torpedo the whole swap and cost me a lot of money.

775068984.jpg
 
Last edited:
I didn't order any special spring cups, so I'd only have what comes with the Bird. I was under the impression that the Bird already had spring cups and so I didn't need to get different ones. If I'm wrong, can you link to those?

They've aborted the whole thing, so I'm stuck with old arms and whatever thermoplastic bushings they're going to dig up for them, freighted in double-quick at my expense. This sucks.
 
Last edited:
dDUBb said:
Maybe because the axle hits the bolt to mount the knuckles ?
Click to expand...

I'm not sure: the shop didn't say beyond "they're not remotely the same", so I have no idea how much work they actually did to try and make it fit and what was it that made them throw in towel. But I keep coming back to how the swap has been done so many times. It's obviously possible.

This is the part where not being a mechanic myself and having to play telephone between all the people who have done the swap in the past but maybe haven't explained everything I need to pass on, and the guy who's tried and failed to do it now, is so frustrating. I don't know what's being left out.
 
Unfortunately, I already told them to go ahead: I can't very well make a shop do work they don't want to do, and I had no real answers to give them on what to do besides "I know it can be done". So I'll drive up to my buddy--the same guy I did my hub swap with--and we'll cluelessly bash our heads against it until we get it. At least the shop will have broken free all the bolts for us and done the other bushings.

It's too bad because they've been a really good shop to me in the past, but I've clearly found the limits of their capabilities.
 
Last edited:
My shop couldn't swap the strut rod bushings and sway bar bushings. They said they did not need the bushings because they came with the arms that I gave them (?), and stopped communication. I would give them another chance if they weren't so terrible at communicating, because I can tell how busy they have since become, and getting new staff. The owner is cool, owns a cobra, and geeks out over our suspension, but I just don't believe he does any work himself anymore

Is there an alternative name for strut rod bushings? Because I talked to another shop who wasn't quite sure what those were.
 
Get the energy suspension poly kit. new spring isolators and toe correctors; You must have the mark bolts with the big torx head!
There were threads with pix at the old site. zod and I did the mod a few years ago. Zod added zerk fittings. which I copied. :)
 
What is the recommended spark plug interval change for our MN12s?
 
100k is the recommended interval for factory equipped single platinums. That might be a tad conservative but it works.

Double platinums are what I use, for all intents and purposes I don't think I'll ever need to change them again.

Copper plugs should be checked/dressed frequently - every oil change - and they typically need replacement every 20k or so.
 
You must log in or register to reply here.

Similar threads

Back
Top