Join Date: Feb 2009
Location: Largo, FL 33774
If you are going to keep it at the original height, you can put the hump in your trans cross member. The pipe will run close to the floor, but you can pretty much mirror the passenger's side. I welded a channel piece from a junk yard cross member to the top of it, then cut the bottom out, and welded the holes closed. with pieces of what I cut out. You can cut the whole way to the inside of the top of the tube. You can bolt a hanger on the end bolt of the drive shaft loop.
If I did it over again, I would clearance the floor a little. I deleted the cat and did not use one on the driver's side. Without the cat, I did not install a heat shield, and do not notice any heat. If you are going to run the pipe along side of the tank, you should put a heat reflective tape on the tank. I put shorty headers on the car as well. One caution is to put the trans in 1st gear when setting up the pipe clearance.
I am running 2 1/2 inch pipes, and I have about 1/8 of an inch sticking below the frame. If you have load leveling, the driver's side muffler will take its place.
I wrapped my headers (they all rust unless they are stainless) to keep the engine compartment temps down. I am trying to be kind to my wiring, and the brake lines beside the driver's side header. You also need to put some insulator material around the area in front of the trans linkage pivot on the frame to keep from burning the wires.
1991 OCC 461 (.030 over 454) BBC, 3.23 posi, flash to pass, drop spindles & springs, Impala rims, Hydroboost, Recaros, MOMO/wood SW w/QR, custom wood shift knob, Pioneer DEH P77DH
1992 OCC now with 5.7 tbi, DEH P77DH
For a parts list, check https://www.impalassforum.com/vBulle...ion-parts.html