700R4 shiftpoint question?
Thread Starter
Joined: Dec 2001
Posts: 9,947
Likes: 644
From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
700R4 shiftpoint question?
Can a bad speedo gear drive, affect shiftpoints on an '83 700R4?
Previous owner claims that tranny was rebuilt about 2K miles ago with a "Corvette servo". The speedometer needle flutters alot and even at WOT the trans shifts at only about 3500 RPM or so - no higher. I was trying to see if there is a connection between the speedo and low shift points.
Previous owner claims that tranny was rebuilt about 2K miles ago with a "Corvette servo". The speedometer needle flutters alot and even at WOT the trans shifts at only about 3500 RPM or so - no higher. I was trying to see if there is a connection between the speedo and low shift points.
Supreme Member
Joined: Apr 2002
Posts: 1,353
Likes: 3
From: Austin
Car: 82 Z-28
Engine: 383 TPI
Transmission: 700R4
Re: 700R4 shiftpoint question?
The computer gets vehicle speed from speedo and controls when to lock and unlock the converter. Other than that, no.
Check TV cable adj for early shifts.
Check TV cable adj for early shifts.
Thread Starter
Joined: Dec 2001
Posts: 9,947
Likes: 644
From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Re: 700R4 shiftpoint question?
Yeah, I adjusted the TV cable. No difference.
And that 'Corvette servo' (if that's what it really is), is just plain annoying. At WOT it chirps the tires hard at it's 3500 1-2 shift point, even breaking the rear loose and causing it to fishtail. And I don't think it downshifts as agressively and effectively as it should either. Hey, I 've got an LU5 and 2.93 gear, I need all the help I can get. And this trans is just not doing it's share.
I'm thinking of just going to a tranny shop and having them replace the servo with a stock one and having them reset the governor.
And that 'Corvette servo' (if that's what it really is), is just plain annoying. At WOT it chirps the tires hard at it's 3500 1-2 shift point, even breaking the rear loose and causing it to fishtail. And I don't think it downshifts as agressively and effectively as it should either. Hey, I 've got an LU5 and 2.93 gear, I need all the help I can get. And this trans is just not doing it's share.
I'm thinking of just going to a tranny shop and having them replace the servo with a stock one and having them reset the governor.
Last edited by chazman; Jun 5, 2008 at 09:22 PM.
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