Ok guys. Im sure half of have already have supercharged ls2's in your 3rd gen and im miles back, but How would this work? How hard is it? What needs to be done? Any year that is specifically a better candidate?
Banned
LT1 is, I believe, a direct fit. I believe that an LT1 will take your stock driveshaft, rear end, and everything else. Make sure you get EVERYTHING tranny related (clutch, pedals, EVERYTHING) from the LT1. Parking brake cable as well I think.
Registered User
make sure u get a complete wring harness uncut unmolested and you will be fine
Registered User
you will need a special crossmember for a t56 in a thirdgen.
Banned
SH*T! Ya, I forgot to mention a wiring harness. Heh.. wont be going to far without that. That WILL be a PITA though 
And yes, you will need a special crossmember for the T56. I used to have it saved as I was going to do a LS1 swap, but I lost it.
I found this:
http://spohn.net/product.cfm?productid=1316
And am pretty sure that is what you are looking for
And yes, you will need a special crossmember for the T56. I used to have it saved as I was going to do a LS1 swap, but I lost it.
I found this:
http://spohn.net/product.cfm?productid=1316
And am pretty sure that is what you are looking for
Registered User
You are all close, but not quite right: I've done it.
The T56 bolts up to your V8 engine block, but it's definitely not what I'd call a direct bolt in project and here's why:
1) Shifter location: The T56 shifter sits farther back than a T5, so you need to trim out an additional 1.5 inches from the rear of your transmission tunnel to get it up into the car.
2) Speedometer: The T56 uses a variable reluctance gear and magnetic pickup to feed speed to a VSS buffer box. Its signal is different than late model 700R4 transmissions, and certainly not a mechanical speedometer like most third-gens. Therefore you need to accomodate for that by purchasing a converter. I bought the SGI-5 from Dakota Digital, a 1987 VSS buffer from a wrecked '87 Trans Am, and an instrument cluster from a late model F-body with electronic speedometer. I then re-routed nineteen of the twenty wires in the dash to accomodate the new instrument cluster. When it was done, I calibrated the SGI-5 and fed the signal to the two required locations: The speedometer and the ECU.
3) Clutch cutout switch: I was doing an auto to manual conversion so I needed to add a clutch switch to cut out the starter unless the clutch was pushed in.
4) The clutch hydraulics are slightly different than the third-gens and you'll need to work on modifying the clutch pedal to accomodate the rod to the clutch master cylinder.
5) Reverse switch takes a different connector than the T5. If you have an automatic transmission, you'll have to cut off the TCC lockup wires, cut out the shifter brackets, cut into the harness where the shifter switches used to plug in, and re-route the reverse switch wires into the transmission tunnel and down to the transmission where you'll use the new style connector.
6) The transmission crossmember will require a custom piece. I recommend the www.skulte.com version since it's light, strong, and fairly inexpensive.
7) If you have a one-piece rear main seal engine, you can use the LT1 flywheel that is externally balanced. Otherwise, you will need one of the retrofit flywheels fron either Fidanza or Centerforce. I bought my lightweight aluminum Fidanza flywheel from Thunder Racing and I love it!
8) Use the LT1 clutch.
You can reuse your existing driveshaft, and if you use the Skulte crossmemer, you can reuse your existing torque arm.
The hardest part of the job is fitting the manual trans pedals into the car if you are converting from an automatic. That part is a pain in the *** and you'll need to drop the steering column and remove the brake booster and master cylinder to do it right.
The T56 bolts up to your V8 engine block, but it's definitely not what I'd call a direct bolt in project and here's why:
1) Shifter location: The T56 shifter sits farther back than a T5, so you need to trim out an additional 1.5 inches from the rear of your transmission tunnel to get it up into the car.
2) Speedometer: The T56 uses a variable reluctance gear and magnetic pickup to feed speed to a VSS buffer box. Its signal is different than late model 700R4 transmissions, and certainly not a mechanical speedometer like most third-gens. Therefore you need to accomodate for that by purchasing a converter. I bought the SGI-5 from Dakota Digital, a 1987 VSS buffer from a wrecked '87 Trans Am, and an instrument cluster from a late model F-body with electronic speedometer. I then re-routed nineteen of the twenty wires in the dash to accomodate the new instrument cluster. When it was done, I calibrated the SGI-5 and fed the signal to the two required locations: The speedometer and the ECU.
3) Clutch cutout switch: I was doing an auto to manual conversion so I needed to add a clutch switch to cut out the starter unless the clutch was pushed in.
4) The clutch hydraulics are slightly different than the third-gens and you'll need to work on modifying the clutch pedal to accomodate the rod to the clutch master cylinder.
5) Reverse switch takes a different connector than the T5. If you have an automatic transmission, you'll have to cut off the TCC lockup wires, cut out the shifter brackets, cut into the harness where the shifter switches used to plug in, and re-route the reverse switch wires into the transmission tunnel and down to the transmission where you'll use the new style connector.
6) The transmission crossmember will require a custom piece. I recommend the www.skulte.com version since it's light, strong, and fairly inexpensive.
7) If you have a one-piece rear main seal engine, you can use the LT1 flywheel that is externally balanced. Otherwise, you will need one of the retrofit flywheels fron either Fidanza or Centerforce. I bought my lightweight aluminum Fidanza flywheel from Thunder Racing and I love it!
8) Use the LT1 clutch.
You can reuse your existing driveshaft, and if you use the Skulte crossmemer, you can reuse your existing torque arm.
The hardest part of the job is fitting the manual trans pedals into the car if you are converting from an automatic. That part is a pain in the *** and you'll need to drop the steering column and remove the brake booster and master cylinder to do it right.
Registered User
The pedals are a pain in the *** but you don't have to actually remove the booster and master cylinder. And depending on the year of you bird all you'll need is the SGI-5 box to convert the signal into something the guages and ecm can read. Grab any trans from 93-97, the 93's were supposedly rated at a lower maximum torque and I think had different gearing and also did not have CAGS. Which you wouldn't have to worry about anyways.
You'll also neeed to wire in the reverse lockout 'noid. There's a special noid that prevents you from down shifting from sixth (or shifting from any gear really) into reverse while in forward motion. I wired this to my brake switch so I have to be on the brakes to shift into reverse. You can just muscle past the noid but why would you?
Good luck, I love my t56.
You'll also neeed to wire in the reverse lockout 'noid. There's a special noid that prevents you from down shifting from sixth (or shifting from any gear really) into reverse while in forward motion. I wired this to my brake switch so I have to be on the brakes to shift into reverse. You can just muscle past the noid but why would you?
Good luck, I love my t56.
Registered User
Quote:
That's what I do, just because " I can" Originally Posted by iansane
You can just muscle past the noid but why would you?
It's like an anti-theft device.
Registered User
i need to bookmark this thread
Registered User
Quote:
Originally Posted by respectirocz
i need to bookmark this thread
Do a search on thirdgen.org for a post from Mrdude_1 about the very same topic. There's so much info in that thread it's crazy.
EDIT: Here, http://thirdgen.org/techbb2/showthre...hreadid=229205
Registered User
Thirdgen.org is definately the best place to check for all that information. They have a whole section on Ltx LSx swaps