I have a couple of qustions about my 2-3 upshift. i have a transgo shift kit and a custom 3200 stall and my 1-2 upshift is awesome but my 2-3 shift is really slow, especially when i run open headers. I talked to the guy who built my tranny and he said i had it shifting too high(6200rpm) and that it would only shift hard at 55-5600 rpm. So I used tuner cat and changed all the tranny tables (ie: normal, performance, manual, and kickdown) so it would shift at 29mph out of 1st and 58 mph out of 2nd. I took the car out and test drove it, the 1-2 shift was right on the dot and the 2-3 shift did not change at all. So i was wondering what i could do to:
1.) get it to shift at 5600rpm or
2.) do something to my tranny to make it shift like the 1-2, like a servo or accumalator upgrades

 

Hmmm...I can't say we have any problems with the 2-3 shift quality in our race rebuilds. Apparently, you're transmission builder doesn't know how to build racing 4l60E's. Unfortunately, most transmission "parts swappers" don't know what should be put in a 4L60E. All 700 / 4L60E's are designed to start dropping pressure at 5000 rpms. Ask your transmission builder if he put a Sonnax "high RPM" slide spring in the pump. If he didn't, don't worry...It only means you'll have to pull the trans back out, so you can get to the pump.

You might also want to try a Fairbanks billet 2nd servo. The Fairbanks unit does away with the 3rd accumulator usually found in the stock "Corvette" servo. We use billet servos in all our race transmission. Yes, they cost a little more, but I prefer to do it right.

What 3-4 clutch arrangement did your builder use? Stock? 9 clutch? Did he reinstall the "load release springs"? The only way to get 3-4's to last is with the Raybestos "Z-Pack", and removing the load release springs. Unfortunately, the Z-Pack costs over $50, so most builders don't use them. We also use the Z-Pack in all of our racing 60E's.

The reality is, your transmission builder is feeding you a load of crap. If you use the right parts, and build techniques, you can make a 60E shift great on the 2-3...even at 7000 RPM's.

Frank

 

Frank Cahall for the win

 

Hey Frank...

Trying to get in touch with you. Are you getting my PMs and e-mails? If not, please let me know so I can resend them.

Thanks!

 

I'd say get a billet servo because Frank said so and he knows tons more than me.
And from my limited 4l60e experience I would suggest the following:
Install TransGo SK 4l60e series L shift inprovement / correction kit shown here. $38.95
and
Sonnax servo release check valve #77701-076 shown here $12.98. It allows modification of the spacer plate to increase apply oil flow to the 3-4 clutch without affecting 2nd gear release. It really improved the 2-3 'shift timing' as well as firmness on my car.
I listed Bulk Part because that's where I bought most my stuff, but I imagine Frank can get you the parts with no problem.
I have only a few pictures of my rebuild that may help a little seen here
and here
Be sure to follow the instructions included with the transgo kit.
Have fun!!!

 

You can modify the hole sizes in the valve body separator plate to solve this. Give me a call and I will walk you through it. The vast majority of the time this can be solved without the transmission coming out. This is assuming that the 3-4 clutches are still in decent shape. I have been using the Borg Warner Hi-Energy clutches in the 3-4 clutch pack for the last 10 years with much success, and have very little 3-4 clutch problems. The Corvette servo will work fine with the matching accumulation from Trans-Go, along with the proper band clearance. Call me at 909 7951876 anytime past 11am PST.

 

Thanks, ill see if i can give you a call on monday the 12th