[j4eubanks]

Been thinking about overdrive upgrade for some time (and no, not just because my TH350 is pissing me off . . . well, not entirely anyways). I got a bead on one out of an 89 Turbo Trans Am that I'd like to throw in my 71 Chevelle. Anyone know of any issues or things to be aware of? Any compatibility issues? I'm assuming that the 89 still used mechanical speedo gears but not 100%. I welcome any input y'all might have for me.
:thumbsup:

 

[zombie1969]

You mean a 2004r right...Ive heard they can be a good trans and an easy swap when you have a t350.I think the cross member needs to be moved a bit for it.I got one in the shed from a grand national that Ill probably never use but for $20 I couldn't pass the deal up.

 

[JAYARTER]

We just did a 192, Il6, power gluide to 327, 200r4 in my daughters 63 Chevyll conv, very easy swap and she loves the car. Kims Nova on my photobucket. I did 69 Camaro PG to 700r4 3 years ago and my wifes Elcamino last month to 700r4. Its harder due to driveshaft cut but both are much better road cars now, and they have killer 1st gear. Jay

 

[richietables]

Not sure about the mechanical speedo or not, but the gas prices are making the swap to OD sound pretty good. 200-4R is the way to go. What gear are you running in the back?

Better 1st gear :thumbsup: than the TH350, too.

 

[j4eubanks]

Currently running 2.73 in the rear. Considering 3.55 posi down the road after OD trans. I read a while back that as a good rule of thumb 1st gear (trans) x rear axle > 10.0 is ideal for good acceleration, and final gear (trans) x rear axle < 3.0 keeps the cruising rpm tame. I did the math and it seemed like 200-4r and 3.55 would be a good combo. I'd be interested to get feedback from the field! Got a lot going on right now, but planning future mods for after my next deployment.

 

[richietables]

Jeremy, a 2.73 won't really be compatible with a 200-4R's .67 OD. It'll really lug, especially locked up. You might think of making the swap to the 3.55 (or whichever) at the same time...

 

[Chevy67]

The 2004-R with a 3.73 works great in my '67. The swap is really easy if you have a short TH350. No cutting, move the crossmember back alittle and you are good to go. I agree with Rich, the 2.73's have got to go for it to really work.

 

[richietables]

I guess one idea would be just to run the 200-4R in 'drive' (1-1 ratio just like the TH350) and don't use the OD until you get a gear that'll be more friendly for the .67 OD. Just my 2 cents...

 

[The Old Reliable]

Was the Firebird the 20th Anniversary turbo-V6?

If so, it also has the Grand National BRF valve body. :thumbsup: