orange1997GT

People on here are always mocking "rustmasters" lol for their drone at highway speeds. I have a flowmaster cat-back and a BBK o/r x pipe. I love the sound. What are they talking about with "drone"? In person I've heard SLP LM1's(on a 94 GT), Magnaflow(86 Z28), Borla(99 GT), and Dynomax(88 Trans Am). The Flowmaster sound to me sounds the best! The SLP is really raspy, but I do like the exhaust tips, they're really big and chrome. I just wish that the Flowmaster cat-back for the 94-98's had bigger exhaust tips!

BraMas

You notice more when your cruising on highways. It's around 2200 RPM's could be different on other cars but usually above 2000. It's an annoying humming sound . Only option is to speed up (speeding) Down shift (burn more gas) or turn up the radio and not talk to anyone in the car with you

cliffyk

The previous owner of my '03 had welded in Flowmaster 40s, at 2100 to 2200 rpm with the windows up it was nearly painfull.

It's a harmonic reinforcement relationship between the frequency of the exhaust pulses (around 140Hz at 2150 rpm), muffler placement relative to the cabin, and the cabin volume/size that can really get cooking...

I now have a UPR catted X-pipe and Magnaflow catback. The cabin noise peaks a bit at 2100-2200 rpm, but it's not as overwhelming as the welded in Flows...

jwarner0297

I don't have that problem with mine, to me its at about 1800-1900 rpms. although some versions of the 40s are different

steve0914

i have the problem thats why i hate my flowmasters... its almost like a vibration inside the car.. its so annoying i can't wait to get a new catback... i think flowmasters sound good outside of the car, buy i hate the drone...

orange1997GT

I thought that noise was how it was supposed to sound lol! I like really loud all the time, people riding in my car are always annoyed. And I have been told that the MAC cat-back sounds good, and they make 3.5 inch exhaust tips. But they're chambered, like Flowmaster.

03FstStngKB

Personally for me from reading all the posts...god knows how many exhaust posts you see on here in a year's time but from reading on here about the flowmasters...I got a sense that it would be unbearable? That has not been the case for me. I am running an h-pipe w/no cats all the way to the cat back portion of the exhaust right thru the mufflers to the tailpipes out the rear of the car. I actually think it's not loud enough till I'm putting some pressure into the throttle but for normal crusin the sound level in the car is not that bad. Now there is a humming or drone noise right around 2000 rpms give or take a few hundred but even with the radio up and windows downs it still is not like what people are saying as unbearable. Going up steep hills which is putting more of a load on the engine it gets a little louder but not nothing to sneeze at.

I had a 91 5.0 mustang and ran 40 series flowmasters on those w/cats and it didn't sound much different than stock. I didn't swap in a h-pipe w/out cats in that car so I just took of the bending pipe that goes around the axle tube and ran turn downs after the muffler and it was insanely loud...I liked it. So that is one way to make it louder inside the car.

steve0914

i agree with you oneqwk, it is quiet when you are not on it and sounds good when you are, but outside the car... i may be eating my words after i get pypes violators, but i went on an 8 hour trip and had a headache the whole time...

russ98stang

i got a borla cat back (or so i think thats what they are) and it can be pretty annoying also, but i dont have my mid pipe installed yet either.

undecided.steve

Hi Cliffyk!

I have the stock H-pipe and the Magnaflow cataback, not the packs, and yes it drones under load at around 2k rpm. Bassani Baffles help, but the drone is still there.

Also I have a vert (2003 Centennial) so it's even worse in my car.

I actually took some measurements, recording the interior noise while driving over the same road and trying to aggravate the drone on purpose.
I sent it all into Sony Soundforge and reached the pretty much the same conclusion you did as far as frequency is concerned.

Note, the Bassani Baffles did reduce the drone frequency by about 3db.

Which Magnaflow system do you have and how do you like the X-pipe/Magnaflow combo?
I'm thinking og dumping the stock H-pipe and going X-pipe but I don't want it to sound "ricer farty" if you get my drift.
I also don't want to make the drone any worse than it is, which is mild compared to the various cars I have been in with Flows..

Here is a screenshot from SoundForge...