Yesterday I was messing around on the highway, took it up to about 120mph and noticed that after 105-110 it got REAL loud....like deafening, around 3500-4000 RPM's. I have 3.73s and an A4, is this normal? I have over 600 miles on the catback if that matters. Hope it's not the driveshaft vibrating or anything, but it sounded like the exhaust droning. It was SO loud though, usually if I go WOT around town not at high speeds it's never that loud.

 

I dont believe my cat-back does that, but I'm never going any faster than 90 mph really and thats rare. My car is fairly loud compared to some others mostly due to longtubes and no cats, but i'll have to check that out though when I bring my car back out in 2 1/2 months.

 

The car has 82,000 miles with factory U joints (as far as i know) and driveshaft.....does it sound like either of these would cause this? The weird thing is that I've had the car to 130 before the catback and gears and nothing abnormal happened.

 

my doesnt do that either, or at least its not loud enough to notice a difference between going that fast and goen 30 at WOT and i have about 4000 miles on mine, but i think as i put more miles on my it got a little louder? hope this helps!

 

I've hit 130 almost daily on the highway onramp here... never experienced what your saying.

 

Your engine really starts to roar above 100 anyway. I don't have the catback installed on my car yet, still waiting to be shipped out here. I have headers though, not really sure what difference that makes in overall sound, but the car really screams when it's in the mid 100s. I took the car to 150-155 the other night and it wasn't deafening loud, but it's still pretty loud. Maybe when I get my Hooker it will be different. Who knows.

 

Alright thanks.....it's probably normal I guess. Sounded like a really loud droning noise similar to what it was like when I was running a cutout.
Sorry, I'm probably just paranoid