silver74vette

I have a 74 with a crate 350, th400 and 3.08 diff. I bought the car and it was set up for drag racing. I have installed the engine, differential and torque convertor. My problem is that my shift points seem very high. With very little throttle input the trans will shift in the 2600-2800 RPM range. I have checked the integrity of the vacuum lines and the trans shifts smoothly and has no abnormal noise from the unit (oh and the fluid level is correct). Is there a simple way to change the shift points of the trans?

Thanks in advance.

redwingvette

I don't think that a car with a 3.08 gear is setup for drag strip. The answer to your question is that if you want to change the shift points you will need to add a shift kit.

virg74

Check the vacuum modulator if it has been changed to a adjustable one that is probably where you need to check first.
Good Luck

any4xx

Run through it at WOT and note the shift points. If they are acceptable, your governor is set right. If they are also too high at WOT, play with the springs/weights on the governor to bring them down. Once you have that set, your part throttle shifts might fall into line. If not, get an adjustable vacuum modulator to tune it in.

silver74vette

Thanks for the info. The gears that were in the car were 5.57s, not the 3.08s that I installed. I have not checked the WOT shift points and am waiting until I have 500 miles on the engine. Is the governor accessable without removing the pan?
Thanks again for the info.

VETDRMS

You running 5.57 gears!? Man that must be a bear just to go 55.

Sounds like it was set up for the 1/8 mile.

You can set the normal throttle shift points with an adjustable vacuum modulator, you can set the WOT shift points by adjusting the govenor.

silver74vette

Thanks for the info, it was set up for 1/8 mile. I was hitting a blistering 42 mph at 3000 RPM but it could swing the rear around like nothing.

Thanks, Chris

any4xx

The governor is under a cap on the side near the tailshaft. Easy access & easier to play with the springs & weights. I'd hit Summit or Jegs for a governor tuning kit. They come with simple instructions and a selection of parts. Easy to mess with.

Tom

silver74vette

Found the trans tuning kit at Jegs. Thanks for the info, I'm not familiar with tuning autos and I appreciate all the help. I will update the post when I get a chance to play with it.

Thanks, Chris

PS, VETDRMS, that is a nice looking 74 you have!