So my 1969 Oldsmobile Cutlass S is finally coming to the point where I can think about exhaust systems. I have a friend of mine who owns a muffler shop and will custom bend me an exhaust but asked me to check if it had a crossover pipe or not and see if it had a double hump crossmember (which it does, whew) but my concern is, can I use the stock manifolds for dual exhaust? Drivers side manifold has a pipe going down and under the motor, and connects to a port on the passenger manifold, then the passenger manifold has a second port that runs a pipe out to the back of the car. The car is all stock and original as it rolled off the factory in '69. Would I have a problem with capping one of the outlets on the passenger manifold, and running dual exhausts on the car? They would exit in front of the back wheels so no concerns other than the manifolds.....

 

The cap goes on the rh front opening that the crossover connects from the lh.The lh would get the new pipe for dual exhaust.

 

Okay cool. Would I run into any problems with the driver side manifold and clearance for a pipe? It exits straight down, at the very back of the manifold, and the pipe goes down and slightly toward the front of the car. There seems to be a hump near the pipe, I'm worried it may hit if I try to redirect the pipe toward the back of the car. Have you done a dual exhaust on a car set up like this? Did you run into this problem?

 

I had duals done like that on my 72 98,my 75 455 cutlass.The current 65 330 cutlass has duals done like that.A good muffler shop can bend the pipe and make it look good to boot.