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Paul Merolla 12-02-2009 02:21 PM

Another transmission question...
 
I didn't want to hijack Rick Lester's thread, so here goes...
Alan and SS3011 - I have a 700R4 in my 68 Camaro and it upshifts way early. When you said output shaft speed affects shift points, my ears perked up because my car has a 4.11 rearend gear. Also, I have the TV cable from Lokar and basically set it up so that when the throttle is wide open, the cable is pulled all the way out. I guess my question is, can I swap governors and cure this? The shop I bought the trans from recommended a Corvette gov.
Thanks

dartman 12-02-2009 02:46 PM

Re: Another transmission question...
 
Changing the governors weight will help to a point.

Alan Roehrich 12-02-2009 07:20 PM

Re: Another transmission question...
 
Yes, a Corvette governor will help. But in all honesty, I prefer to use a Superior valve body kit to raise the line pressure, as well as the big TV and low/reverse boost valves from TCI. I also use the Superior TV valve kit, as it helps line pressure rise. Getting really good line pressure rise makes a 700 R4 used in a hot rod work better and last longer.

I used all of that in the 700 R4 in my Cutlass which has a 4.11 gear. It works like a champ. The part throttle shifts are nice and crisp, and very well timed, the WOT shifts are very clean and firm, and also well timed, although I usually shift it manually at WOT.

I NEVER use a TransCo or TransGo shift kit of any kind in ANY 200 4R or 700 R4. They seem to give the absolute worst line pressure rise of any kit made. If I get a valve body that has one of those kits, I'll replace the valve body, I simply won't work with any of those kits.

Paul Merolla 12-03-2009 11:46 PM

Re: Another transmission question...
 
Thanks Alan. If I were building a fresh trans, I'd do all that, but this car is in no position to want $$ or time spent on itself that would delay stocker project needs...sooo, I'll look into a vette gov and call it good.

ss3011 12-04-2009 10:21 AM

Re: Another transmission question...
 
If all you have is a shift point problem, then buy a B&M governor kit. The kit has governor weights and springs, and a set of instructions, so you can reconfigure your governor. Most GM transmissions that rely on a governor to shift them, are calibrated with a combination of valves and springs in the valve body, and the governor. So my recommendation is to start with a known calibration set, such as a valve body and governor from a Camaro, or Corvette, and then tweak on the governor using the B&M kit. Small changes will keep you from getting out into left field .

tranzbuilder 12-05-2009 12:52 AM

Re: Another transmission question...
 
I was curious which upshifts are to early wot only or light throttle or mid throttle. there is many ways to change all of them depending gear ratio, tire size, geometry at the carb center to center distance from throttle shaft to cable stud. most good transmission shops should have asked you those questions before building the unit ! also curious about the statement the other gentlemen said about NEVER using TRANSgo products in 2004r or 700r4's what inside those kit's causes the worst line rise ever? thank's for listening

Alan Roehrich 12-05-2009 08:52 AM

Re: Another transmission question...
 
I don't know exactly what it is TransGo does. But I've fixed dozens or complaints by taking the TransGo stuff out, provided whoever installed it did not do the permanent modifications. The absolute best thing you can do for either transmission is use the big TV boost and low/reverse boost valves, and a good pressure regulator spring.

Paul Merolla 12-05-2009 11:18 AM

Re: Another transmission question...
 
Quote:

Originally Posted by tranzbuilder (Post 154806)
I was curious which upshifts are to early wot only or light throttle or mid throttle. there is many ways to change all of them depending gear ratio, tire size, geometry at the carb center to center distance from throttle shaft to cable stud. most good transmission shops should have asked you those questions before building the unit ! also curious about the statement the other gentlemen said about NEVER using TRANSgo products in 2004r or 700r4's what inside those kit's causes the worst line rise ever? thank's for listening

Light throttle, as in every time I stop for a light and take off again. It was an ebay purchase, not a trans built for me. I should also say that I've been very happy with the trans all in all...when I take it to the track and shift it manually, it works well and shifts are firm enough to break the tires loose. (no slicks...8.2" 10 bolt time bomb)

tranzbuilder 12-05-2009 06:41 PM

Re: Another transmission question...
 
If your only problem is light throttle upshifts corvette govenor will not fix that problem. What carb do you have on the car? should be able to fix your problem pretty easily with lengthening the center to center distance from throttle shaft to the cable stud. it's just a matter of correcting the goemetry at the carb to match factory linkage inside the transmission.

Alan Roehrich 12-05-2009 07:31 PM

Re: Another transmission question...
 
Paul, that's a lack of line pressure rise. If you'll get the pressure regulator spring and those two valves I told you about, that will fix a lot of that. Get the two biggest valves TCI makes, you can pick them up cheap at Jeg's or Summit. A transmission parts house will have a Superior valve body kit. Outside of that, you'll need a pan gasket, a filter, some Vaseline, and some fluid. You do not even have to drop the valve body. Everything you need to work on is behind a snap ring in the pump.

If you have a Holley carburetor, you may want to pick up the piece they make to go on it to improve the geometry for the cable.


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