Imo Apita
Well-known member
- Joined
- Feb 28, 2009
- Messages
- 244
The irony if the situation; I pushed my '79 'vette to the side for blowing the transmission and now my new project has a bad transmission also.
In any case:
The dynaflow two speed is toast on my recently bought '63 Lesabre.
I have the following options:
Rebuild it if no hard parts are damaged
Replace with a TH400 from a Jeep Wagoneer which is a bolt on.
Replace with a 700R4 which requires a $800 conversion kit.
I'm torn between the 400 and the 700R4.
With a gear ratio calculator figured out that at 80mph the engine rpm is 2300 with the 700r4 and 3200 with the TH400.
Question is it worth the extra $1000-$1200 for the modifications such as TV cable bracket and so on.
The 700r4 has a 3.06 first gear vs a 2.48 for the TH400.
I understand the torque multiplication thing but considering the Buick is about the same weight as a Cadillac (4200 ish) how much difference would a 700r4 really make compared to a TH 400?
I would like a high way gear for sure but not really convinced its worth the extra expense.
How much faster does a 4000 lbs car really accelerate with a 3.06 first gear.
The rear gear ratio is 3.23 for the Buick by the way.
Any help appreciated as I need to pull the trigger pretty soon on this one.
In any case:
The dynaflow two speed is toast on my recently bought '63 Lesabre.
I have the following options:
Rebuild it if no hard parts are damaged
Replace with a TH400 from a Jeep Wagoneer which is a bolt on.
Replace with a 700R4 which requires a $800 conversion kit.
I'm torn between the 400 and the 700R4.
With a gear ratio calculator figured out that at 80mph the engine rpm is 2300 with the 700r4 and 3200 with the TH400.
Question is it worth the extra $1000-$1200 for the modifications such as TV cable bracket and so on.
The 700r4 has a 3.06 first gear vs a 2.48 for the TH400.
I understand the torque multiplication thing but considering the Buick is about the same weight as a Cadillac (4200 ish) how much difference would a 700r4 really make compared to a TH 400?
I would like a high way gear for sure but not really convinced its worth the extra expense.
How much faster does a 4000 lbs car really accelerate with a 3.06 first gear.
The rear gear ratio is 3.23 for the Buick by the way.
Any help appreciated as I need to pull the trigger pretty soon on this one.