In Reply to: What do "decibals" have to do with power? posted by Greg I on December 23, 2000 at 02:25:01:
I don't think it matters if "DTM tips" are single, dual, or quadruple. In the DTM they used to route the exhaust tip(s) upwards so that they could squeeze out a couple more decibals of sound (freer flowing exhausts for more power) without getting penalized. Not sure what the allowable decibal was unfortunately. Anyway, this awkward direction of exhaust tips eventually became the hot item for people on the street... I was told this by a former employer, but I trust he wasn't BSing me since he had entered numerous E30s in the DTM.
Whenever I see cars with "DTM tips" I always grin. Do they know why they're called "DTM" or why they're even curled upwards? One day i'm going to design my own exhaust that will extend 10 feet above the rear bumper and see if people catch on ;)
Future Super Duper DTM Exhaust Owner!!
Decibels are a measure of sound; sound does not correlate to the power of an exhaust (hell, run the car without headers and rev it up -- not only will you eventually destroy the engine, but you will get an absolutely thunderous roar; make sure you're standing back and wearing ear protection).
I also fail to see how the length of the exhaust tip itself has any sort of significant bearing on what kind of horsepower your engine produces.
I think what he was saying was that by having the the tips pointing away from the sensor they could get away with running a less restrictive exhaust which was louder instead of running the quieter more restrictive exhaust.