New Gears vs. New Tranny?

[West]

In my 68 Firebird 400, I have a TH350 and 3.73 gears in a 12-bolt rear-end. The engine has about 450 horsepower and over 500 ft-lbs of torque.

Here's my problem. At highway speeds the engine turns over way too fast for me.

So, I either need to change the gears (something like 3.08), or change the tranny to an overdrive tranny (like a 700r4).

Obviously, if I change gears, I could lose some acceleration, although with this much torque I might not notice it. Also, if I change trannies, I would probably need a seriously strong 700r4 to handle this kind of power.

Thoughts?

[chicane67]

2004R.

Do a trans... it works out in more ways for the better for you, especially your mileage and wear and tear on your drivetrain. you couldd even paddle shift it too.... http://www.twistmachine.com/

The 700 has a weak point that isnt evident in the 200. The 200 is basically the TH350 of today with an overdrive.... and all the strength and lighter weight of a TH350.

Read the following about both the 4L60/700 and also the 2004R. This cat builds all of the high hp/tq 200's for Dutwiler and the 800+hp turbo buicks he builds. Its some good information, but dont always take one opinion as the gospel. Do your homework and get as many opinions as you can before you form your own, educated opinion on this subject matter.... as I am sure there is going to be both sides of the 200 vs. 700 comparison and different facts supporting both choices.

4L60/700: http://www.drwtransmission.com/4L60E.htm

200: http://www.drwtransmission.com/thm_200-4r.htm

[Bandit]

Go with a manual conversion and drop a TKO 600 in there. Get to keep your steep gears, and have a 4-speed with an overdrive in a trans that will laugh off your 500lb-ft of torque.

C'mon, everybody's doing it!!

[ItalianBullitt754]

As Bandit says "DO IT"