The overdrive would be better but it would be much more expensive. You would have to buy quite a few parts in addition to the transmission to convert it over. It would also be more work.
A 200-4R would be much closer to a bolt-in. A mag did that on a '67 GTO with good results, and I'm sure others here have also used the 200-4R. Worth a check at least.
ok im back, so if i was to change gears ,what would be the best opt. dyno out of car at 359.3 at5000 and 387 torq, 17inch wheels and i wanna go highway then light to light
If you want to go highway at all 3.55 is the ceiling without overdrive. My 69 has 3.55 and after about 50 miles at 80 mph I'm ready to 'give it a break'.
High Performance Pontiac, a six part series starting in April '98. They use these behind the GN Buicks and can handle 500 hp fairly easily when built. Some say they are easier to built for that hp level than the 700-R4.
I used a '200r4' and it was not a hard swap at all. Run a 3.70:1 rear gear. I like the way it works for me. I like to spend a lot of time on the highway.
For the 200 there are very few 'special' items needed. That is why I chose the 200r4. I believe a company called "shiftworks" does have some stuff for the shifter itself. Most all of the rest can come from the parts store. In some cases you'll need to get parts for the transmission's application or an application that uses that transmission. In many cases it is a simple matter of common sense and practical engineering. HPP's articles on the changeover is very informative.
