angcobra

Well, got the tranny out and took apart. The failure was the splines in the front drum. The hardened shaft did it's job but the drum splines did not. Tranny guy said he has never seen this failure.

wildcobrar

I feel for you on the parts breakage. I truely believe the C4 when built right will do more than you need for your HP. There must be a few soft issues left in there.

rmodel65

i went through 4 c4 trannys when i had my 351c in my 72 fastback i would literally hear them sling parts inside i kept breaking bands i finally built one myself with extra clutches and steels it lasted till i dropped a valve now the engine sits in my room lol but it was fun while it lasted i was getting the left front tire off the ground with a3.00:1 open rear!

angcobra

New TCI forward drum has been delivered to the tranny shop. I hope to get the tranny back within a week.

angcobra

New TCI hardened drum in and car back together.

On trying to keep the HP down on the stock block, I decided to shift at 5000 RPM and just run the 1/8th.

First trip to the track (with the 4th tranny) yielded 6.60 @ 102 mph (when I shifted at 6000 it was 6.30 @ 110). The shifting at 5000 may not work out for the current torque converter because it never seemed to totally hook up and I stayed on the shift light just about the whole track.

Maybe a few more adjustments and go again.

angcobra

Tranny seems to holding together now. I have about 10 runs on it now with no problems. The short shifting at 5000 RPM is yielding times of 6.50 @ 105. I guess not to bad for keeping the power down on the stock block.

myshifter

properly built C4's hold together no problem

angcobra

Update. Got about 20 runs on the tranny now. Now shifting at 5200, most recent run was 6.47 @ 109 (should have been better but 60' was slow due to spinning)