Has anyone ran a sbc 400 with a 700R4? I have a 406 with a 700R4 behind it and it keeps spinning bearings, thrust bearing some wear but not alot. I have heard from more than one person that the 700R4 will cause this. When put together checked converter and everything looked ok. Any ideas or options would be great!

Thanks,
Mike

 

Has anyone else heard this, help would be great

 

i have not had any problems with mine. but i wish i went with the th350 conversion instead of paying 1600 for the 700r4

 

How do you like that trans and motor set up? Are you running TPI, what rear do you have, and what are your highway RPMs?

 

I have never heard of a 700R4 do this, but the TH400's did this behind 454ci. motors. They took out the crankshaft thrust bearing. There were different solutions to solve this. If you want to make sure that the 700R4 is "not" doing this. You will have to look at the stator support as to the condition of the teeth that go into the torque converter. The splines must be in very good shape. If there is wear here, the torque converter (especially if it has been replaced) can catch on it and sometimes this will put pressure on the back of the crankshaft when the line pressure inside the torque converter rises. The reason that this does not happen with a 700R4, is that it never had torque converter pressure issues that the TH400 had. But you could possibly have this. Are you running a boost valve that is bigger than the .500"?

 

I have not been able to keep a 700r4 alive, 5 units in 2200 miles and never seen the track. It is not a daily driver. These units were from different people all fresh builds with lots of goodies in them. Saving up for a TKO 600. Not wasting anymore money on these trans. They work fine with low torque and hp motors. My original trans lasted 125,000 with the 305. Just my 2 cents worth.

 

Pro built- the trans is stock and when assembled the converter went on with no problem no binding or anything.

Larry I have also decided to go to manual route unless other ideas come about.

Does anyone have or have a lead on a WC T-5 swap complete minus flywheel.

Thanks for the help guys

 

its a 406 carbed 3.42 gears posi .but like i said i wish i went with the th350. i think this 700r4 is on borrowed time. highway rpms ? hardly ever on highway with it.but the over drive is good to have then.

 

"the trans is stock and when assembled the converter went on with no problem no binding or anything."
It will go on ok, you have to inspect the splines, as this is where the hangup occurs when under load. If the step is in such a way that it will cause it to "hangup", it can put forward pressure on the torque converter, which might cause the problem.

 

You could always go with a 2004R