Rotti54

Hey guys I have an 82 Trans Am in super nice shape, but my long term plans are to put the original motor and transmission on a stand and build it up. I'm up in the air whether I should do the easy TH350 swap or go with the 700R4. Whatever trans I go with it needs to hold about 500hp 480Tq. What are your thoughts? I know some of you must have done this swap what were the pros and cons, unexpected issues etc??? Thanks you for any info

NoEmissions84TA

iTrader: (1)

The TH200 can be built to handle more power than a 700R4 and has a better gear spread. It's also lighter. Bonus for you - no conversions.

skinny z

If my information is correct, the 82 Bird is more likely to have the TH200C. That was a 3 speed automatic. At least that's what was in my 82 Z28.
The TH200R4 is the overdrive unit that has good potential. It's also the one that matches the TH350 in length and mounting locations. (As per NoEmissions post above).
The TH200C to 700R4 swap would require a different crossmember but everything needed is OEM and readily available. Not sure about overall case length as it relates to the driveshaft.
You might want to verify my bit of info though.
FWIW. The 700R4 can handle your power requirements. For a short time on the cheap. Spend more on better hard parts and it'll last a long time.

Rotti54

Thanks skinnyz I appreciate the info.

sofakingdom

iTrader: (1)

Right the 200C is a giant piece of dung, not even adequate for a 6-cyl let alone even the weeeeeeeniest V8 such as a LG4. The 200-4R is a COMPLETELY different transmission; not so much as the slightest internal resemblance of even one single part (well, maybe one... I think the extension housing bushing might be the same); not sure why they used the same model # for it, but w/e.

An 82 chassis lacks the rearmost bolt holes for the 700/T-5 crossmember. Although, it wouldn't be too hard to mark and drill them, then hole-saw through the floor pan right above them and tack-weld a nut inside the "frame" thing, then put a hole plug over the hole. You'd need a shorter drive shaft as well.

A 350 is easier in that you can re-use the crossmember and drive shaft you have now (if you use the right 350), but then you lose the overdrive advantage of the 700. Best choice would depend on what you intend to use the car for.

Rotti54

Honestly I'm not going to be on the highway much I think I may just go with a built th350 done soup to nuts rated at 500-650 hp somewhere in that range