Summit 2.5" exhaust

I bought the Summit 2.5" kit because i needed mufflers and tail pipes. The Mandrel bent pipes are really nice, and it came with the Summit turbo mufflers.

I got around to installing it today on my car (69 Dart Swinger 340) For now, I just used a bushing to go from my existing 2 1/4" head pipes to the 2 1/2" mufflers. The over the axle pipes and tail pipes went together very easily. I needed to trim an inch or 2 off each to get the right fit, and I cut the tailpipes short so I could attach the new 2 1/2" reproduction tips I have.

The driver side over axle pipe was not perfect, I think it was because my existing head pipe had too much of a bend at the muffler connection, causing the muffler to angle out toward the rear tire too much. Any way, I cut the axle pipe, clocked it slightly, and welded it back together. The rest was pretty straightforward.

The Summit mufflers produce a DEEP mellow tone at idle, and are pretty quiet at cruise speed, but at 1600 to 1800 rpm, or any time you accelerate at 1/3 to 1/2 throttle, there is a deafening drone to the exhaust.

I did find a big leak at the passenger side manifold to headpipe connection, so I will fix that and hope that it quiets the drone. I did check, the exhaust does not hit the body anywhere and there are no other leaks.

Anyone else have this issue with the summit mufflers?

The kit is designed to be a complete header back system. Future plans include using the rest of the pipes in the kit, and then fabricating connections to the manifolds. The passenger side is pretty straightforward, but that driver side HP manifold, pitman arm, starter and torsion bar maze scares me.

Anyone here custom make you own down pipe? any tips for the drivers side? Can it be done with 2 1/2" pipe?