C-4 shifting too soon

[manyolcars]

This C-4 shifts out of first within a few feet of starting away from a stop. Its about the same as starting off in second gear. What can I do to let the engine rev higher before it shifts? Manually holding the shift lever in "low" is not an option. Thanks

[shoebox72]

What is your rearend gear ratio? Ive experienced this problem when putting a late engine/automatic trans in an old car with an original low geared rearend. You may have to switch to a higher geared rear,one that prefferably matches the one in the car you got the trans out of .Got it?

Billy

[beatnik]

Is the throttle kickdown hooked up? If it's a stock C4 that has to be used or that's exactly what the trans will do.

[manyolcars]

[ QUOTE ]
Is the throttle kickdown hooked up? If it's a stock C4 that has to be used or that's exactly what the trans will do.

[/ QUOTE ]Yeah, its hooked up but who knows if its right. A neighbor just bought this 34 Ford with 302 and C-4. I know nothing about C4s but would like to help him. What is the proper set up for the kickdown cable? Its connected at the Caburetor with a short chain.

[shifts]

A couple things to check: Modulator pin is too short or someone has left it out.Modulator leaking fluid. Feel free to call me if you need more help. (715) 835-0128 Dave

[manyolcars]

The downshift cable is stuck. Its not doing anything.--Hey, Shifts --How do I identify the trans, what downshift cable do I ask for?

[HOTRODPRIMER]

Try unhooking the throttle kick down and give it a go....

I'm not sure about a C4,but some 350 turbo transmissions have an adjustment screw in the modulator valve. HRP

[manyolcars]

Thanks, I already did that.

[andysdeuce]

On my boys Mustang we adjusted the kickdown linkage behind the carb and it seemed to help it a little. Also have him check the modulator on the tranny....if tranny fluid comes out of it when he disconnects the vacuum line then he probably needs a new modulator valve. They are cheap and easy to install. We put a new one on the boys c-4 and it made it shift a lot better.

[Curly]

I was just reading another post with a link in depth on this exact same thing! Here is a link:

http://www.nationaltbucketalliance.com/tech_info/drivetrain/tranny/tranny.asp

It put a whole new twist on what I thought I knew.

[Flatdog]

The first thing to check is the modulator. Is it push in or screw in, and what is the color os the stripe on it. What size motor are you running and what kind of vacum are you pulling. C-4s with shifting problems used to give us fits in the old days. Most cars shift by electric signal now. The questions I'm asking are very important for dialing in a C-4.

[Cadillacin Marcus]

B&M Transpack kit works wonders on the C4 as well as a nice stall converter

[manyolcars]

Hi Flatdog. A neighbor just bought this 1933 Ford truck with C4 and 302 (we think). We really know very little about it but tomorrow I will get under it and look for the modulator. Thanks Bruce