Inliners International Forums General Discussion Engines Exhaust size effect - is bigger always better?

JimW- bear in mind, usually if you just pull the muffler off it will be slower - down low and also sometimes even up on top!

You have to generally kick the timing up a couple degrees, and jet up say 3 numbers richer. These changes will NOT help with the muffler on. But now, when you uncork it, if the open pipes are the right length, you will hear a roar out the headers as the rearend fishtails from the low end, and your friends will hear the car from 4 miles away as it sings at top end. BTDT!!

J78: If you still have the stock 250cid in there (about 140hp gross, 110net) I'm not sure that you need more than a single 2", since 2" duals are plenty up to near 300hp, a 2" single is plenty up to maybe 140-150hp, no need to go bigger.

Its more like BIUB (Bigger Is Usually Better), but BINAB (Bigger Is Not Always Better)!