3.8 L to 5.0 Swap

LXSC

Registered User
I need to know what is necessary to install a 5.0 L engine into a 1990 Thundebird. Will the existing engine cradle and K-member holding the 3.8 L and AOD tranny be able to hold a 5.0 with a T5 tranny. If modification needs to be done, what does it include? Thanks for all assistance.
 
well

get mounts out of a 5.0 bird-91-93 5.0 was offered. the trans (t5) wont work without a shifter extension box-it will go in but you will end up punching the dash in 1, 3, and 5. the k member is perfectly capable of holding the 5.0, and the t5 is lighter than the aod. Id recomend an m5r2-stock vs. stock-its a stronger tranny, just have to be gentle with her. LOL-good luck, mike
 
Clarify

"the trans (t5) wont work without a shifter extension box-it will go in but you will end up punching the dash in 1, 3, and 5."

What does punching the dash in 1, 3 and 5 mean? Can I find a shifter extension somewhere? Or can I just find a built M5R2? I want a built one since I'm thinking around 500 hp.
 
M5R2 Question

Would an 88-96 Ford F150/250 tranny work? What modification or anything would be needed? Would this be a better fit in a 90 LX (originally an auto as well)? How can this transmission be improved to handle 500 hp?
 
okay-no, a truck trans wont work. punching the dash means just that-when you go to shift into 1st, 3rd, and 5th gears, your hand will hit the dashboard as the shifter on the t-5 is too far forward. you need an extension box to relocate the shifter a few inches farther back. the only tranny that goes in without much effort is the one that came in it-the t-bird/cougar m5r2. the truck version is completely different and wont work in the bird. good luck, feel free to pm me if i can help. Mike
 
I just dropped a 91 couger 5.0 in behind an M5R2 last week. I used a starter and flywheel from a 95 f150 (5.0 5 spd.) and it all bolted right in. It was amazingly easy. You will need tbird headers, mustang headers wont fit (done a lot of looking on this). There are a few other little things to do but nothing major. Do a search for it, there is a lot of info out there on this. My only problem right now is the wiring. There is not a lot of info out there on this issue. I compared all of the pins on the eec last night and there is not a lot of difference between the two. There are only 6 or so wires that are different. I a lot of guys are replacing that harness, but I may just re-pin where i can and splice on the 5.0 engine connectors.
 
I have toyed with the idea of putting a V8 into a SC myself. One thing I never fully figured out is what using a V8 EEC would do to the ride control since the ARC has a feed from the VSS. I'd like to hear how others have worked this out.
One thing not yet mentioned is that you'll need the T-bird oil pan,either from an actual Tbird or a SN-95 Cobra.
What intake are you thinking about? I have a Cobra on mine and hood clearance is minimal,so if you want an intake that'll flow for 500HP you'll need a cowl hood.
Good luck!
D
 
What intake are you thinking about? I have a Cobra on mine and hood clearance is minimal,so if you want an intake that'll flow for 500HP you'll need a cowl hood.

Not if you turbocharge it. :D

Here is a pic of my 93 SC with a dart block 347 installed w/a Victor Jr. carb intake conveted to EFI with a custom upper plenum. The oil pan required with the dart block was pretty deep and required serious cutting/welding on the k-member and raising the engine 1" to clear. But I'm still under the stock hood. It's just about ready for the turbo kit.

347%20turbo%20062904%20002.jpg


347newmotor.jpg


David
 
Hot86MustangGT said:
I have toyed with the idea of putting a V8 into a SC myself. One thing I never fully figured out is what using a V8 EEC would do to the ride control since the ARC has a feed from the VSS. I'd like to hear how others have worked this out.
One thing not yet mentioned is that you'll need the T-bird oil pan,either from an actual Tbird or a SN-95 Cobra.
What intake are you thinking about? I have a Cobra on mine and hood clearance is minimal,so if you want an intake that'll flow for 500HP you'll need a cowl hood.
Good luck!
D

If you use a Tbird donor car none of those things are an issue (well except for a decent intake manifold).
 
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