Side Pipes

[RonNichols]

I put together a couple sets of side pipes this last spring and tested them on the local dyno. The first set was a 3" x 22" Classic Chambered with a 7 degree transition from SPD Exhaust. I made the transition just slip inside the factory SPF collector such that when welded, looked like a standard SPF side pipe and it funneled the exhaust into the muffler from the 3.5" collector to the 3" bore smoothly. I ended up with an extra 40 ft-lbs of torque and 31 hp over the factory set up on a Mustang dyno. But it was the whole area between the new curve and the old curve that made it a completely different car performance wise. Beyond 2100 rpms, it just left the factory muffler in the dust.

Figuring bigger was better, and having an extra partial set of side pipes to play with, I put together a set with a Megs venturi collector and a Howe 3.5" racing muffler. I made more noise but I actually lost 7hp and 11 ft-lbs of torque over the 3" bore mufflers. These tests were done a month apart from one another so direct comparison I guess can't be done. I would like to put together a set with the Megs venturi collector and a Classic Chambered 3" bore muffler to see if I get some power back and trim some dB's.

I love the sound of the 3.5" setup though, and the Megs collector to me looks great and has a racey look to it. I may just stop here and send my welding fixture I made to another SPF buddy of mine to play with. All in all, it was a fun experiment and I learned alot.

Hope this helps.

R