T5 to C4 Conversion....help...

I am currently converting my 90 GT T5 to a C4 automatic. Does anyone know what all is involved. I havent been able to find any automatic crossmembers around my area so I couldnt compare them to see if they were diff...also drifeshaft length? Any help would be appreciated. Oh yeah and I am moving my engine back 1" Will this have any impact as far as cross member?
 
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smr said:
I am currently converting my 90 GT T5 to a C4 automatic. Does anyone know what all is involved. I havent been able to find any automatic crossmembers around my area so I couldnt compare them to see if they were diff...also drifeshaft length? Any help would be appreciated. Oh yeah and I am moving my engine back 1" Will this have any impact as far as cross member?


I just don't grab the concept, all these ppl wanna go from an auto to a t5, and your ass backwards. Stinky ATF and power robbing automatics, not to metion fuel economy. I love givving the ol 5.0 a little clutch and lettin her loose. Have you driven one be4 cause i would never concider this in a million years, remember it's a sports car not something your grandma drives. Even if i was only going in straight lines i still can't grasp the concept.
 
driveshaft length is the same. you can modify your crossmember to make it work by grinding off the welds. i dont think moving the engine back one inch will have an effect on the crossmember at all. it will probably work out better that way.
 
I agree on the crossmember. I ground the welds (stock T5 crossmember) and slid it all the way forward on the tubes to install the C4, so that 1" setback will be fine. I used the stock driveshaft out of a V8/T5 car and I imagine you will have 1" to play with but if not, you might have to have the shaft shortened 1".
 
thanks

thanks for the info...I was told by serveral auto "hating" t5 owners (nothing against T5 owners. I own another one as well) that it would be costly and I would need a new cross member and supershort drive shaft. Thanks again for the info.
 
C4s rule!
Big stall and nitrous the T5 boys will be like WTF at the track.
I just got my C4 back from being built and will be swapping the T5 out of the car tomorrow.
I'll be sure to take lots of pics and post them
plus I might need some help along the way
great thread guys keep the possitive info coming.

JL
 
I have thought of swapping to a C4 also. It's going to be really hard to manage a manual with my new motor, but then again, it's fun as hell to bang gears. I wish I could "test drive" a C4 reverse manual valve body and a trans brake.
 
swap is going well
I got the T5 out today
replaced the rear main seal (just in case since it was there)

I will flush the convertor tomorrow and mount the flex plate
The C4 was in the car before. I got it with the T5 in it. The C4 was wasted do to an improper build.
 
smr said:
thanks for the info...I was told by serveral auto "hating" t5 owners (nothing against T5 owners. I own another one as well) that it would be costly and I would need a new cross member and supershort drive shaft. Thanks again for the info.

they dont know what they are talking about. the driveshaft wont need to be shortened at all. at any rate, the c4 that is in my car is lighter than the tko 500 that i took out. and thats including the bellhousing on both and the clutch and converter
 
here it is
 

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I still just don't grab the concept, but i guess everyone has different tates and preferences. I guess if we were all the same no one would be cool, and after all with out second and third how would we ever decide who was first. Good luck with the swap i'll be looking for you in my rear view later.

Dagz
 
Good luck with the swap i'll be looking for you in my rear view later.

Most guys who swap to C4s are running 11s or better. The C4 is an outstanding choice for several reasons- it handles big power/torque and allows more precise shifts than any manual clutch transmission can. Plus, any automatic with a high stall, the right gears, and sticky tires will dominate out of the hole.

Most of the real fast guys that I've seen are running a C4 or C4 style transmission.

So, Dagz, what do you have to backup the big talk?