Hi Everyone

We own an 82 Indy Pace Car fully optioned. Unfortunately the previous owner replaced the rear differential with a 4th Gen rear end. I have sourced an 89 posi, disc rear end & replaced all wheel bearings & seals etc, now rebuilding the PBR callipers & brake lines. Due to the low ratio gearing (3.27) I want to get a bit more fuel efficient open road running out of her so my thoughts were to fit a 700R4 to give me that extra gear on the open road. As we are way down here in New Zealand, there are limited options locally.

Can anyone advise me on any fish hooks in doing this? Our car has no computer due to its age so not sure how the overdrive would be activated?

 

If auto and stock, you have a TH200-C (TH200 3 speed auto with lockup.) U.S. models had ECM, Canadian may not have. You should be able to re-use existing TCC wiring to lockup the torque converter clutch in a TH700-R4 or TH200-4R. The connector may differ. And if yours is removed, there are aftermarket lockup kits.

Your stock throttle valve cable is re-used with either.

The 200-4R is the same length as stock and the mount is further back. Any dual pattern (Chevy and BOP) bellhousing pattern unit bolts up (they made some BOP only units.)

The 700-R4 needs to be V8 car or truck and is 2.92" longer.

The 700-R4 crossmember bolt holes were added to the floor in 1983. So you have no fully bolt-in option. While you could shorten your torque arm and bolt it to an F-body 700-R4 tailhousing mount, mounting to the crossmember is better for trans. mount life.

I have owned and driven a few and favor the 200-4R, which has the dame 1-3 ratios as TH200. A nice stock higher stall converter with lockup should make drivability nice for a cruiser.

 

Thanks for your comments. Since I posted this, we realised the trans being offered to us was the TH200c, not TH200R4. I have now secured a low mileage TH700R4 trans. As the bolt holes are not in the chassis for the later trans, I can fit captivated bolts to suit the longer trans & shorten the driveshaft. I was even thinking a building an aftermarket crossmember to mount the rear of the trans as it should & mount the torque arm swing mount as per the attached.

 

When I did a trans swap in my 82 I added the extra bolt holes in the frame. It was pretty easy.

 

How did you do the captivated nuts in the chassis?

 

I used the crossmember as a template for location of the holes. I drilled holes in the frame slightly larger than the bolts I was using. The holes were about 3-4 mm wider in diameter than the bolt. I sourced grade 8 nuts and bolts. Took some 2 or 2.5 inch wide steel stock and cut it so it was 2.5-3 inches long and drilled a hole the same diameter as the new hole in the frame. I welded the nut to the plate. Then used tape to affix a long piece of 2-3 mm rod to feed the nut plate combo through the oval opening in the frame. Once the nut plate combo was where I wanted them on the inside of the frame I got the proper bolt partially threaded. I drilled two small holes in the frame next to the bolt head on each side. The holes were probably 7(ish) mm each. I drilled through the frame so I could see the plate the nut was welded to. Then I welded to the plate to the frame and filled in the 2 7 mm holes. The heat from the welding released the tape holding the rod that was affixed.


I hope I explained it well enough. If you have questions let me know.