Contour Enthusiasts Group Archives Forums Modifications Duratec Performance Would a exhaust leak make a exhaust sound "Boomy"

Do exhaust leaks have that much effect on the sound of a exhaust system? I just replaced my intermediate pipe between the MSDS "Y" and the beginning of the catback exhaust with a 2.5" hi-flow cat and pipe, but I had trouble lining up the 2 bolts for the catback and the end of the new cat converter and I'm not real sure if it is a good seal. Anyone have a leak right there then get it fixed and have the exaust sound drastically different? If it doesn't then I'm pissed cause it sounds like shizzle and tomm morning I had a appointment to get my rear ultraflows replaced with bullets cause it wasn't loud enough, now I'm torn. Anyone know if a cat takes time to break in and sound good, I also had to tilt the cat at a 45 degree angle to fit because Stanzi took the "S" out of it like there is on the stock one, would that have any impact?

I think they might make your exhaust note sound a bit muffled on acceleration and putty (almost backfireing sound) on deceleration.

Do they have any affect on pwr/tq?

Possibly louder (bigger leak) Depends on size of leak

Definitely hear that "putty" / leaky sound

Yes they cause a small loss of power.

That putty leaky sound must be what I am hearing when I let of the gas and decel up to a stop. I must have a leak there, still unsure if I'll swap the rear mufflers though, I have a appt in 2 hours! Thanks for the replies

I always thought exhaust leaks made it very whiny and high-pitched.