Finally got the trans swap done (C4 to T400) and car is back on the road. Thought I might list parts used and some installation notes.

- JW "Wheel" flexplate which has dual bolt patterns for a 4 bolt Ford or 3 bolt Chevy converter.
- Crank adapter (allows smaller Chevy converter hub to fit tight in Ford crank pilot hole).
- JW SFI bell for SBF to T400.
- TCI trans shield.
- Turbo Action shifter (easy to convert from C4 to T400 with different gate plate)
- Homemade trans crossmember with Energy Suspension poly mount.
- Mark Williams billet trans yoke
- Dynotech custom moly 3" driveshaft with 1350 solid u-joints.
- Strange 8.8 yoke for 1350 u-joint.

Notes:
- Trans tunnel needed some massaging with a BFH to clear the shield, but not too bad.
- Standard shift lever for 400 will not clear the shield. Turbo action makes a special lever for trans shields.
- The Turbo Action bracket that attaches the cable to trans pan needs to be cut down in order to clear shield.
- The deep aluminum pan I got from Dynamic did not have a bung for trans temp, so I drilled and tapped a mounting hole (works good).
- Turbo 400's come with different output shafts and you need to know which you have in order to get the correct trans yoke.
- The biggest difference in output shafts is if it has a tapped hole down the center. Mine did and required a special yoke.
- The factory trans crossmember will hit the trans pan. You have to move it back about 6" and come up with a new way to attach it to the car, or make a setup from scratch (what I did), or pay some $$ for a AJE unit.
- You have to mount the trans in the car in order to properly measure for driveshaft length. Most driveshaft companies tell you where to measure from.

Rob

 

is the drive shaft length a huge difference? i have an alum frpp and wanted to see if just changing the yoke would be acceptable?

 

so what do you think about the th400 so far? to what degree has your trans been modified? shift kit, reverse manual vb, or transbrake? what converter and stall?

 

I can't answer that. Too many variables. You would have to install the trans and then measure shaft length needed.

Rob

 

how about a glide? thats the same length as a t5 right? i got one laying around with a tbrake. will my sn95 brake that being to heavy?

 

So far so good. I had the first road test on Saturday. Drove about 60 miles with no problem and then smoked a brand new vette! Trans is supposed to be built for 1200hp with rev manual and Tbrake.

Rob

 

No clue...

Rob

 

by the way thanks for the heads up on m post. hes been awesome to deal with and knows his shit going back on wednesday i think to finish up the tune

 

Yeah, Mike's a good dude.

Rob

 

You did good to get that TCI shield in there.. Mine didn't come close to fitting.. That's whay I used a ballistic blanket..

 

I remember that you had problems and I was worried, but decided to try fitting a shield in there. Maybe my motor sits lower than yours :noidea: I have an AJE K member and some solid motor mounts. The only really tight area was on the passenger side of the tunnel from the firewall to about 1 ft. back.

Rob

 

Rob,

If you don't mind me asking, how much was the driveshaft?

Thanks,
Mitch

 

Just curious why guys wouldn't go with a C6 (that bolts right to the motor) instead of going with the TH400?

 

More readily available performance parts for the TH400 (internals, converters, yokes, etc.).

Rob

 

I bought a PDI/Mark Williams TH400 billet trans yoke off eBay. New they're $200 from Mark Williams (http://www.markwilliams.com/detail.aspx?ID=295), but this guy was selling it for $85.00 (used Nascar piece). Anyway, my concern was fitment. It slid right on and seems to be in a good forward position...I think. Also, I noticed 2 flat spots (opposite of each other) on the inside of the trans yoke. Are they suppose to be there, if so what are they for? What do you guys think?

Output Shaft:





Trans Yoke:





Trans Yoke Splines: - Are those 2 flat spots suppose to be there?





Fitment 1:





Fitment 2:

 

subscribing for the info.

 

This is a 4 year old thread. As many people are switching to GM transmissions, it would be good idea to make a sticky from scratch.

 

Yeah it would definetly help out alot with things like this. Ive been wearing this search button out!