Running duel exhaust out of manifolds
 

I'm going to run a dual exhaust on 77 lemans. I need help on where to mount the hangers on the car. I don't really want to drill into the floor of my car to mount them in the floor. Any advice?

I think hangars are usually mounted to the frame not the floor. I would just duplicate the mount locations of an earlier car that came with dual exhaust. Might need an earlier cross member.

On earlier model LeMans, the hangers were positioned on the frame cross member just forward of the rear end and then on the frame rails near the fuel tank or just rear of the fuel tank. This may have been different on a '77 due to catalytic converter and single exhaust but with duals it should be fine. Also, some exhaust shops mount to the trans crossmember by simply welding a length of threaded stud or bolt to the trans crossmember and bolting the hanger to that. Are you building your own system or using an aftermarket system? I ask as I don't see much available in aftermarket dual systems that will boilt up to manifolds except one offered on E-bay for '73-'74 Cutlass. which should fit your car i would think.

I guess I'm kinda building my own, as I've got the header back exhaust system from summit. Then I've got the down pipes for a 69 to 72 that pypes makes. I've had to cut off quite a bit from the summit kit but should have it all bolt up tomorrow.

Success took me bit but it's all ran time to run clamps and hangers

Well both sides are done up. Had to put a custom hanger on the driver side. But never say never to having true duels on a late model a body.