Reddragon88gta

I was looking into this mod and when looking at the TransGo site they stated this came on TPI Corvettes and "high performance" Camaro and Firebirds. I did a search but could not yield an answer...I don't want to go through the trouble of installing one of these if it came from the factory with it. I have a 88' L98 GTA largely stock and am assuming it may already have this is servo if TransGo is correct. This is also a popular modification on our cars and I am just curious if anyone can verify this.

TTOP350

iTrader: (8)

I have heard it came on the B4C camaro but not sure on anything else. Dana @ Probuilt may know more

Reddragon88gta

The guy at TransGo did not know, that's why I threw it out here. I'm debating on going with the Vette servo and maybe an Edge 2500 stall in the spring, I have a pretty mild build as seen in my signature and 3.27 gears but a lot of guys seem to say the stall will give it a nice boost even on largely stock cars.

blacksunshine'91

iTrader: (10)

I highly doubt that an '88 GTA had a corvette servo. Maybe the 1LEs or B4Cs might have them, but I would find it very unlikely that run of the mill production cars had them at that point.

Reddragon88gta

That makes sense, I forget that when you order certain parts for these cars they offer a performance option(like brakes) and its the 1LE or police versions that deem that classification. I think that probably settles it then.

daferris

iTrader: (8)

My '88 5.7 IROC did not come with the Corvette servo.

Reddragon88gta

Did you install a Corvette servo? If so did you like it as opposed to stock?

BHR

no they didnt thats why it was called the corvette servo, only 4th gens 4l60s had the corvette servo in them stock

go with the sonnax 2nd gear servo it has more area then the corvette servo and still uses the cushion spring unlike the superior super servo

if your changing the convertor also drill out separator plate feed holes larger high stall convertors soften all your shifts

Reddragon88gta

Thanks for the info, I’m not looking for something really extreme just a little more than stock to give it a quicker 1-2 shift but the sonnax looks like a quality part, lot of choices for this and I want a quality servo. I saw global transmission had one that is drop in ready to go but do not know much about their quality

BHR

the servo from that site is the corvette servo
https://globaltransmissionparts.com/...y-700r4-4l60e/

you dont need all that the rest is the stock stuff cover, 4th servo, cushion spring, return spring ect. that you already have, the piston is the only difference and what makes it shift faster and harder
https://www.ebay.com/itm/4L60E-700R4...sAAOSwsR5fhy0X




this servo has the most apply area and shifts the fastest and hardest but a cushion spring cant be used and the shift is very harsh if the separator plate holes arent made smaller than stock


in this page its just two servos the corvette piston, the complete superior servo, the superior 2nd piston only and the complete corvette servo which is the first item on the page with the rest of the stock components
https://globaltransmissionparts.com/...vos-governors/

Pro Built Automatics

Until the 4L60E, the Corvette servo was only in Corvettes. With the 4L60E, the Corvette servos were available in Hi-performance TA's & SS Camaros.The newer Superior Super Servo uses the steel cover and cushion spring. I don't know if the old sty;le is still being made by them. They are very similar to the Sonnax servo, without the dual apply sealing rings. The reason that the Corvette came about, was as horsepower improved, the 2-3 shift started having a 2-3 shift flare at WOT. The Corvette servo helped solve this problem, along with the .471" main boost valve and sometimes the .296" intermediate/reverse boost valve, available in the Corvette. The .296" intermediate/reverse boost valve firms up the 1-2 manual shift at all throttle openings. Another benefit of the Corvette servo, was improved 3-4 clutch life. I use these in the vast majority of my builds. Once I get over 675 FWHP, I use the Sonnax Servo, or the later Superior Super Servo. If below 675 FWHP, and the driver, drives very aggressively. I will add the larger servo.

BHR

i have not seen a 4l60 from any 93 f body or 4l60e 94-02 fbody not have the vette servo in them stock no matter what model they are

for the superior servo where do i install the cushion spring?

imo they are not similar to sonnax the superior has the largest apply area and the shifts and downshift clunks are the harshest

Pro Built Automatics

I stand corrected. I forgot the 1993 700R4 in Camaros & Firebirds had the Corvette servo. I mentioned the later Superior Super Servo that has the ability to use the cushion springs. The earlier Superior servo, could not use the cushion springs.