700r4 build, what is a vette servo?
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700r4 build, what is a vette servo?
ok so i want to build my trans i was thinking of a transgo shift kit most people on here agree but what is a corvette servo? what does it do? and what do i need to make it shift from 3rd to 4th in WOT i seen this (you can either block the Detent passage in your Throttle valve plunger bushing, or just replace the plunger bushing with an
aftermarket one from companies like Superior. The GM Valve kit is P/N 8671953. It replaces the 3-4 shift valvetrain) but i wasnt sure about what to look for in this mess
aftermarket one from companies like Superior. The GM Valve kit is P/N 8671953. It replaces the 3-4 shift valvetrain) but i wasnt sure about what to look for in this mess
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Re: 700r4 build, what is a vette servo?
Don't you read? I just explained that yesterday in Rusty Vango's thread.
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Re: 700r4 build, what is a vette servo?
Blocking the detent passages is by far the cheapest way to go. ($1.25 vs. $40.00 - $60.00) The GM valve kit is for the early 700R4's if I remember correctly. The TransGo Shift kit when setup correctly will give you smooth part throttle shifts and firm WOT shifts. The Corvette servo was designed to improve the 2-3 shift. As horsepower was increasing the 2-3 WOT shift began to exhibit problems, such as a 2-3 shift flare (transmission neutralizing). The 2nd gear servo is the 3rd gear accumulator. Increasing the band release area slows down the band from coming off to fast, thereby forcing more 3rd apply oil to the 3-4 clutches. This will prevent the "shift flare" that was/is somewhat common when using the factory 553 2nd apply servo. This was using the stock six clutch 3-4 setup. Just adding the Corvette servo will also give you a firmer 1-2 & a slightly quicker 2-3 shift. The accumulation needs to be addressed to keep the 1-2 shift from being to firm. The TransGo (Junior & Senior) Shift kit does this. The 700-2-3 Performance Shift kit does not address this. Remember, you want smooth 1-2 part throttle and quick WOT shifts.
Last edited by Pro Built Automatics; Jul 5, 2012 at 04:55 PM.
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Re: 700r4 build, what is a vette servo?
Blocking the detent passages is by far the cheapest way to go. ($1.25 vs. $40.00 - $60.00) The GM valve kit is for the early 700R4's if I remember correctly. The TransGo Shift kit when setup correctly will give you smooth part throttle shifts and firm WOT shifts. The Corvette servo was designed to improve the 2-3 shift. As horsepower was increasing the 2-3 WOT shift began to exhibit problems, such as a 2-3 shift flare (transmission neutralizing). The 2nd gear servo is the 3rd gear accumulator. Increasing the band release area slows down the band from coming off to fast, thereby forcing more 3rd apply oil to the 3-4 clutches. This will prevent the "shift flare" that was/is somewhat common when using the factory 553 2nd apply servo. This was using the stock six clutch 3-4 setup. Just adding the Corvette servo will also give you a firmer 1-2 shift. The accumulation needs to be addressed to keep the 1-2 shift from being to firm. The TransGo (Junior & Senior) Shift kit does this. The 700-2-3 Performance Shift kit does not address this. Remember, you want smooth 1-2 part throttle and quick WOT shifts.
Transmission slipping?
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