TM 200 4R swap

[Lawfree]

I am finally getting my 84' GN 8.5" rear installed in my 80" Cutlass Calais. I plan on swapping out the Turbo 350 with a 4 spd 200 4R. I added a G force crossmember to the project so I could run dual exhausts. When I bought it they told me that it would work with the 4 spd auto with just the addition of a frame rail extenetion. I just got a reply from G force and Now they say that it won't work and I'll have to buy an all new one. I've been scrimping and saving for a long time to get a regular
200 4R re-built to hold up behind a fully built 73' Rocket 350, and REALLY don't want to spend another $200+ for another crossmember. None of the MFGRs will tell me why it won't fit and I'm getting alot of mis-information and conflicting answers. G force says none of their crossmembers will work in a Cutlass Supreme and I know that's not right because I put one in myself.
With just some rough measuring it looks like the crossmember I have just needs to be moved back a ways. Any advice of info on this would be greatly appreciated.

 

[Bonnewagon]

That doesn't sound right. Who sold it to you and which part# do you have? I am useing the 2004R/T-400 unit and it came with the short frame extension, which is nothing more than a short piece of rectangular box tubing. They want $100 for it but I would make my own if I needed one again. http://www.crossmembers.com/g-body.htm

 

[DrRansom442]

why specifically did they say it won't fit? Did you not buy the extension too? and if it won't fit why are they not offerring a calltag to pick it up with a full refund? With the notable exception of the frame extension ANY crossmember for a G-body fits ALL 78-88 Cutlass. If there crossmember doesn't fit your 1980 A-body then it obviously fits NO G-body cars either.

 

[FE3X CLONE]

This sounds like the STUPID header myth on the older Cutlass Supreme's. You'll notice that most header companies will list a header as fitting a Cutlass but not the Cutlass Supreme. No body know's where or how this myth was started but there IS NO difference between a Cutlass or Cutlass Supreme frame.

Somehow this has now carried over to a G-body Cutlass Supreme and even more odd, to these aftermarket crossmembers.

If you bought a TH-2004R crossmember, then its going to fit just fine and you tell G-force to screw themselves. What other crossmember would they want you to buy???
I've installed two G-force crossmembers into two different Cutlass Supreme's and both fit fine. I did have to do a little floor board manipulation but that's it.

 

[jae]

Definitely agree with the Dr. and the rest. If you talked to them and they sold you the one with the frame extension and that's the one you bought then it should work. If they sold you the wrong one, they have to send you an RAF# so you can return / exchange it - they should also pick up shipping.

As stated, what p/n did you order? Who did you talk to at G-Force when you originally ordered it, and who is now saying it won't work? Did you get an extension with it?

In any event, something's wrong with this picture. I'm running a G-Force crossmember and it bolted right up.

 

[DrRansom442]

I'm using a factory Xmemeber but their extension. So I'd say there isn't anything different about the mounting locations. Perhaps Andy can elaborate on the BFH work .... was the crossmember THAT tight a tolerance to the floor pan?

As for the age old header myth thing. For some odd reason my 260/th350 sat right were they should. When I instaleld the 350/200-4r with all new mounts ... I did find everything sitting about 1" forward and 1" inch offset. Dunno if it was Advance's great India made mounts but we could NOT get it to sit right. A trans mount for a Turbo Regal fixed all issues ... seems they are offset from the factory. Ofcourse what throws a wrench into the "Cutlass Supreme theory" mines a Calais.