Check out the photo "dual exhaust" I had a problem with
my supercharged engine overheating, and I noticed the super high
heat paint burned off my muffler. I drilled and tapped my muffler
and installed a gauge. I had 7 lbs. of back pressure, that's a no
no! I checked my F.O.R. and it had 4 lbs. You want 1 to 2 lbs at
most. I put the dual tailpipes on the muffler and brought the
F.O.R. down to 1.5lbs. I put the muffler back on the Hot Shot and
still had 2.9 lbs. I then cut the muffler open and removed 2 of
the 4 baffles. I ended up with 1.3lbs of back pressure. Now the
engine revs up quicker, sounds much better, and no overheating
anymore. Barry
Chevy1943 – Summer 2009
Pulled the 7/8" exhaust off last night and ran an open header. Significantly more power! Had to richen up the needle because it ran leaner. I've got to make an 1 ½ inch exhaust and a nice flowing muffler now! Anybody make a 1 ½" exhaust pipe pre bent?
Slackline47 – Summer 2009
I just put 1 ½" exhaust and a 12" glass pack on our Crosley runs and sounds great. We had it custom made. It's tight going over the rear axle.