Exhaust pipe material vs velocity

Bruce_Hearn@cd-tech.com Bruce_Hearn@cd-tech.com
Wed, 1 May 2002 15:20:59 -0500


All the muscle car magazine articles I've read over the past twenty years
indicate that once you're past the collector(s), go as big as you can.  Pipe
size tuning is mainly ahead of the collector, especially with stepped or tri-Y
headers.  I've never read of an instance where power was lost as exhaust pipe
diameter went up, though I did see one mention that power was lost with an open
header.

Once you've wrapped an exhaust attempting to keep velocity up, the O.D. is the
same as just going with bigger, cooler pipe.

I'm going to try to dyno some different pipe sizes while I build my race car.
These will be shorties strictly to satisfy sanctioning rules, but it should be
generally applicable to street exhausts.

Speaking of which, all you poor college kids need to start saving your lunch
money.  My Courtesy cat-back will be up for sale in about six weeks.

Bruce in Houston
'94 SE-R w/ lots 'o $tuff