Suda

Okay my goal is to take a 93' Camaro T56 and mount it to a NP233 transfer case in my S10 ZR2. To do this, I plan on running a corvette tail/ extension housing with a custom adapter plate, and relocating the shifter to the access plate on the main housing. So on with the questions...

What all parts will need to be changed in order to run a corvette tailhousing on an Fbody transmission? It would be nice if the answer was none, but I highly doubt that is the case. I would think at least the shift rail would need to be changed.

Anyone have any idea how far the F-body output shaft will stick out of the corvette tail housing? Too much is okay (to some degreee) as I can just eat up the extra length with my adapter plate. If not enough, anyone know what the lenght differences is to a corvette mainshaft or how much it protrudes? Also, I've heard GTO output shafts are a different length. True? False? Length?

Am I going in the right direction, or do you think it would be easier to try to convert from a corvette transmission to what I need? I do need the gearing from a 93 Camaro, so if starting with a corvette t56 I would have to replace gears.

Also, does anyone know what all is involved in relocating the shifter to the access plate? There are numerous kits that go for $300-$400, but I was curious if it was something that could be done for cheaper.

Thanks for any help. I know there are some really sharp people on here when it comes to the T56.

jmd

iTrader: (4)

Shift rail length needs cut. / the functionality of the seal on the f-body mainshaft to y-body tailhousing seal is a question of mine.

GTO mainshaft is the same length as the F-body

You can't run a 3.35 first M28 gearset (double/single cone synchros) with a Corvette nor GTO mainshaft (triple/double.) Which means you're stuck w/ the double/single compatible f-body or Dodge or Ford mainshaft if you intend on going M28 ratios.

Chasing the granny first gear of the M28 also leads you to a narrower 4th / countershaft gearset weakness up front. Not a huge deal with a ZR2 in the 3700lb range but except for 1st gear, the SSR trans. has it allllll over the M28. Is the NP233 set up for a 27 or 32 spline trans. output?

I love your project but the cost / work involved is going to put you more reasonably towards a late model 5 or 6 speed truck trans. that will have good truck ratios already. If you were doing the fab work you could do the access plate shifter mod but if your time is worth anything $300 is quite reasonable.

85MikeTPI

iTrader: (9)

The Y-body (vette) tailhousing seal rides on a machined surface just behind the extension bearing. The Fbody/GTO mainshafts don't have that surface as they begin their neck-down to the 27-splines right in that region.

I believe RSG made a similar adapter for a Sy-Ty T56

Not the same one, but same idea in post#277 of this thread:
https://ls1tech.com/forums/advanced-...advice-14.html

I think you'll need a vette T56 mainshaft to work in that situation, and doing it with a mid-shift might be tougher. It might be something the SSR 32-spline mainshaft could work for though, since it does have a machined VSS surface where that seal would meet..

Suda

Wow, thanks for the great responses. It's great to have a community with such a weath of knowledge.

The NP233 has a 27 spline input.

Would that all apply to the M29 ratios with the 2.97 first or what would be different? The M29 would be great gearing for my project.

Unfortunately weight is a huge factor in my project. I know this may come as blashpemy on this site but an LS is actually not going to be the motor for this particular project. I will be running a cummins 4BT 4 cyl turbo diesel which weighs 745-782 lbs wet. So I'm looking for a relatively light transmission that can handle 355 lb-ft of torque from a diesel that is harsh on transmissions to begin with. If you have any lightweight suggestions with close to the M29 gearing, please let me know.


They actually make one for what I want too, but the price is outrageous and I can't get any information out of them. I've thought about just bucking up and buying the adapter kit, but then I wouldn't learn anything :/ I don't know. It is an option.

When you say mid-shift are you refering to the shifter location? Why do you say it might be tougher?

And unfortunately I need a 27 spline output.

Thanks again for the help.

85MikeTPI

iTrader: (9)

Yes, if you're not putting the shifter behind the vette tailhousing, you wouldn't have the spread available to use the vette mainshaft length.

jmd

iTrader: (4)

The 2.97 first gearset was also used on triple/double boxes including GTO & some Vettes.

I like the idea of a 4BT but a 4000lb S-series doesn't appeal to me at the same time. I've weighed a '94 RCSB 4.3 A4 on local scales.

SYRacing

iTrader: (2)

I am also doing a similar build, but I started with an 04 GTO T56. I got a rear housing from a vette off of ebay. Any idea on what length to set the rail? There is no provision in the new tail section for the shaft and I was planning on doing a front shift like the OP.

$1300 - $1350 is what I was quoted with no provision for a mount and the 6 bolt transfer case flange is NOT drilled. This is supposed to allow flexibility to let the end user clock the case. He also stated that they use a different output shaft.

After several calls to George (none returned), emails and contacting their sales department, I determined that if I cannot get ahold of somebody there to take my money then what will happen when I need tech support?

I've got $50 into my adapter setup and should receive my plates soon. I'm planning on using some 5" tubing I had laying around at work between the 2 machined plates. I need to get a 4L60E to check what the output shaft stick out length is before I weld the tubing to the adapter plates. I'm pretty sure its flush but need to make 100% sure.