GM to Ford tranny swap possible?

[oxiderush]

I'm trying to put a c-4 in my 89 firebird formula. It has a t-5 tremec(borg warner) that won't shift into 5th or reverse. What special bellhousings or brackets would i need to make the swap?

[MagicRat]

You would need a machine shop and a couple of engineers from NASA. Do you already have the C-4 transmission? It is a bad idea to base a component swap just based on parts you have lying around.

The biggest problem is that the bell housing and torque converter is quite differnt than a GM transmission in terms of bolt pattern and size. It simply would not bolt up to your engine unless you did extensive metal work and fabrication. There are no adapters because GM cars had their own excellent automatics. Also, the transmission mounts and shifter are not compatible between the C-4 (Ford ) trans and the GM chassis.

The C4 trans is not such a good unit. It has a 3 speed trans with no overdrive (4th) gear. Most had no lock - up torque converter and it is not particularly strong, unless modified.

If you want an automatic you are MUCH better off using a stock GM 700 R4 (if you have a 305 V8) or a 200 R4 (V6). The best way is to get one from an automatic Firebird of that year, so you get the console, shifter, trans mount etc.

However, your car is worth more and is more desirable if you keep and fix the stock T5 transmission. It's also cheaper than doing the trans swap.

[public]

Originally Posted by MagicRat

You would need a machine shop and a couple of engineers from NASA. Do you already have the C-4 transmission? It is a bad idea to base a component swap just based on parts you have lying around.

Hey!!! I say go for it.

AMC made an entire corporation out of this "Plan of Action" I had one with a International Harvester Block, GM distributor, Chrysler Ignition with ballast resistor(God I hated those things), Ford Alternator, and I believe a Ford Tranny. The entire car seemed to be made out of an Adapt-O-Kit.

So call NASA (1-800-rocketscience), get some engineers, and order yourself a CNC milling machine (a new Cinncinnati is always cool at $100k) and have fun..

[MagicRat]

Originally Posted by public

AMC made an entire corporation out of this "Plan of Action"

Yeah, I have an '84 AMC Jeep Cherokee with a Chevy engine, GM steering column, Chrysler transmission and transfer case, Steyer/Puch torque converter (from Austria) and Ford electrics, glass (Carlite) and switch gear.

[curtis73]

I think transdapt could help you with the tranny adapter.

At any rate, I applaud you for using non-traditional parts, but I don't think the C4 is a very "worthy" tranny for all the work you'd have to put into it. Its a fine tranny, but nothing special. You're looking at a custom crossmember (or mods to yours), a custom driveshaft, custom adapter, custom flexplate or TC, custom shift linkages and speedo cables; all for a tranny that is no better than a TH350.