200R4 mods for a heavier car

[techg8]

I thought Id ask the 200R4 experts for opinions:

I am swapping a 200R4 (86 Cutlass) into a 72 Buick Skylark 350 (~315HP,360Torq) that will not be revved over 5000RPM.

It is a heavier car, and I am looking for suggestions on what mods to do to the trans.

Currently I am planning on leaving the stock frictions in there.

I have a CK Performance shift recalibration kit on the way, I have a D5 converter I will use, .5 TV boost, .296 lo/rev boost.

Is a performance servo a must-have?
Am I headed in the right direction?
What are your thoughts on the trans core I am using?

My plan is to run it with relatively light modifications until it gives up, then I would consider a full performance rebuild.

thanks for any input.

 

[SSedan64]

The Cutlass may be heavier than the Skylark. CK's kit should help alot. Servo can't hurt, GN or better.
Replace all the seals you can get to & fluid/filter before the install. I'm no trans expert.
What code is the trans?

 

[techg8]

What code is the trans?

BM81 7-15-80

Thats what is stamped on the tag.

 

[KL Mallender]

I would suggest that you check and verify what rear axle ratio you have in the car right now before you begin, if your car is equipped with a 2.73-3.08 I would advise you NOT to update to the overdrive, using an overdrive on top of such a low(numerically) is asking for disappointments, it will be VERY difficult to maintain overdrive let alone lockup with such a combination.
The benefit of the 200-4R is the ability to use deep gears(3.73-4.56) for acceleration without the penalty on the highway, turning less rpms sounds great except you will most likely be driving around constantly in "power enrichment" mode, negating any benefit of less rpm. I have done many conversions into the older cars using 200-4R/700R4 and can honestly tell you nothing will run better than a nice 200-4R backed up with a 4.10(2.74 final in OD) Good luck.

Kevin.

 

[techg8]

thanks for the reply.

I am running a 3.42 posi 8.5" 10 bolt rear in my 72. My motor likes that ratio the best, runs GREAT with my combo in gears 1-3. I specifically wanted to put in a 200R4 to reclaim highway abilities at reasonable RPM, since I will be driving the car to some tracks this summer. I am glad you can relate to what I am trying to accomplish.

 

[KL Mallender]

10-4,

A 3.42-3.73 will work very well(Buick and Olds liked'em )
You will gain what you seek, good job on the homework.

Kevin.