Hi guys. I have an aftermarket C6 R code servo that came with two springs. One light and one heavy. Which spring will give me the hardest shift?

The tranny flares up a bit between 2nd and 3rd, what else might cause this other than the servo?

 

Worn direct clutch.

 

How about on a year old rebuild? Street/strip car with less than 500 miles per year. Its a C6 behind a 460 with around 650 HP with the nitrious. I just put in the R code servo and it didn't seem to help much. I guess I will try the heavy spring next, as I put the light one in on my first try.

 

One year, ten years.

The direct clutch is 3rd. gear.

A heavier spring will detract from 2nd. gear.

Oil pressure must increase to overcome the spring tension and the release will be that much quicker.
If you have a worn clutch assembly or excessive clearance this could make the flare worse as the band releases before the clutch applies.

What has been done to the valve body?

 

The valve body has not been modified by me, but it is an aftermarket unit. Probably a TCI?

My transmission builder is a chevy guy and doesn't seem like he knows all the tricks for a C6. I have limited experience with some C4s. If the vavle body needs to come out, are there mods to make it right or should I start saving for a new one?

 

The C6 rebuild video advertised on this site, I believe called Bad Shoe Productions (you can check the site banner) is very helpful. You watch a complete teardown and rebuild with points all along the way on how to modify the C6 for performance and endurance. You also get a parts list if you want to put in bearings or low ratio gear set. All in all worth the money for yourself or to pass on info to your tranny builder.