Transmission Crossmember Modifications:
In order to accomodate dual exhaust with
full-length headers, some modifications to the stock crossmember
Click here to see how I installed a 700-R4 trans into my Monte using the stock crossmember.
Monte Carlos and other G-bodies used different crossmembers depending on year and/or transmission. Most Turbo 350 and Turbo 200 equipped cars used a "diagonal" style crossmember (this is the one my car has). When the Turbo 200-4R became available, A "straight across" style crossmember was used. Some early 80's cars can use ONLY the diagonal-style crossmember. Later years had mounting bosses on the frame to use either style crossmember.
The passenger side of the crossmember is designed to clear the stock cat and single exhaust pipe. On the drivers side, there is no clearance, forcing you to bend the pipe under the crossmember, which is not optimal. To correct this, I notched the stock crossmember (A). I marked the part that needs to clear the exhaust pipe, then cut it with a sawzall. Being the crossmember is hollow, I used some 3/16" x 2" wide steel to box off the notched area(B). The pieces were traced onto the 2" wide steel, which I then cut using a sawzall and a hacksaw.
Once the steel was trimmed to fit, I had a buddy weld it. It's not the prettiest thing, but it works. Just for kicks, we added some triangular supports to the sides (C). This is probably not necessary. I hit it with some black Russel frame epoxy spray paint before bolting it back into the car.
This gave me enough clearance for 3" pipes. G-Force Performance offers custom made crossmembers.
Here is my finished exhaust system. Click on my exhaust page for more info.