89 Tranny Question
Thread Starter
Heel & Toe
Joined: Nov 2008
Posts: 15
Likes: 0
89 Tranny Question
This may sound like a stupid question but here goes.
My latest vette is a 89 convertible with the automatic trans.
I have had a 89 coupe auto and a 85 auto. Both of those cars shifted very hard. It was very easy to grab second with those cars.
I have a friend locally here that has a 86 auto and it too will grab second every time if you get on it a little.
My 89 convertible shifts very smooth but not hard like the other cars I have talked about.
Does anyone know if the convertible has some differences from the coupe cars?
This is my first convertible and really dont plan on doing many mods rather just restore it have something to do but it would be nice if it shifted a little harder.
Any input guys
My latest vette is a 89 convertible with the automatic trans.
I have had a 89 coupe auto and a 85 auto. Both of those cars shifted very hard. It was very easy to grab second with those cars.
I have a friend locally here that has a 86 auto and it too will grab second every time if you get on it a little.
My 89 convertible shifts very smooth but not hard like the other cars I have talked about.
Does anyone know if the convertible has some differences from the coupe cars?
This is my first convertible and really dont plan on doing many mods rather just restore it have something to do but it would be nice if it shifted a little harder.
Any input guys
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
The 700r4 (and most transmissions) have a jigger called an accumulator. The accumulators job is to cushion the shift. 700r4 has 4 of them. They are set using specific springs, with specific spring tensions. Manipulating these will make it shift with any firmness desired. They can also be locked. Most shift kits manipulate these accumulators.
Toss a brown spring in the 1-2 accumulator, and a white spring in the 3-4 accumulator.
Toss a brown spring in the 1-2 accumulator, and a white spring in the 3-4 accumulator.
Drifting
Joined: Aug 2002
Posts: 1,774
Likes: 125
From: Birmingham AL
It is likely that your transmission was rebuilt and the builder did not use the Corvette parts for replacement. Aamco did this to my previous Vette and it shifted like an Impala or something. The original Vette transmission should have a firm shift. Maybe not as firm as some aftermarket shift kits, but not sloppy either. There are Vette specific springs, a governor, and a servo if I remeber correctly. And stay away from Aamco as they like to put 7 transmissions in your car in 18 months. 
