Kenny2428

Ive got a 2006 base A6 car. The car has Texas Speed headers, no cats and has also been cammed and tuned by 21st Century Muscle Cars. Anyways the car still has stock mufflers but the previous owner drilled a 1 inch hole into each muffler. It actually sounds pretty good, but the drone is insane. I know Corsa Sports are very popular because they dont drone or atleast they dont drone on a stock engine with stock manifolds. Does anyone here run the sports on a cammed engine with no cats? Also I am kind of leaning towards putting the NPP exhaust on with a mild to wild switch. I just dont want to spend a ton of money on the Corsas and they still drone.

jaybee924

The best thing to do is get the stock NPP mufflers for your years car and add the mild to wild and be done and cheaper also. Loud when you want it quite when you want it. Drone is subjective best to play it safe than be sorry in the end.

Soneat

NPP mufflers will give you drone free in low rpm when you want it, and loud w/ drone when you do with mild 2 wild setup. Even in the mild setting, the mufflers open up in the upper rpm. Really is a great setup.

old motorhead

Is that something new? I had NPP in a box a while back and it stayed closed as long as you had it in the quiet mode...no matter the rpm.

To the OP, I had Corsa Sports behind a supercharged LS3, cam, long tubes with no cats. Virtually quiet at cruise on flat terrain. If you had to go uphill, you could hear a little exhaust note, but nothing I would classify as "drone". More of a purr. At WOT, it's another story. My son was positioned at the 1/8 mile mark during a 10 sec quarter mile run. He said it sounded like it was eating asphalt at it passed by.

I have ZR1 bi mode mufflers on this Vette. As jaybee said, a dual mode exhaust is the best of all worlds. Even with cam, LT's, and no cats, it's totally quiet at cruise. At WOT, it's louder than the Corsa Sports.

Dave S

That's an oxymoron with your set up....the cam & cats delete change the harmonics in the exhaust so even a setup that's reported as "drone free" by others may or may not give the same results for you. IMHO you'll have to make the best choice you can & then keep your fingers crossed that you get what you're looking for.

Kenny2428

Yup, thats what im thinking also. I will give the NPP exhaust a shot.

old motorhead

You'll be just fine. I've had all three of the GM bi mode C6 Mufflers. Actually two sets of NPP's on two different cammed LS3's with no cats. My current Vette has ZR1 mufflers which replaced 2010 and earlier Z06 cans. All cammed with Long tubes and no cats.

The NPP and ZR1 mufflers are the loudest with the flaps open. The early model Z06's are quieter with the flaps open vs the other two. They are all about the same with the flaps closed. No drone what so ever.

rc51racer

I just installed Kooks 1 3/4 Long Tubes no Cats and added NPP exhaust plus NPP in a box kit on my 2005 Z51 6 speed.
Quiet no drone when valves are closed and loud when open. I really like it!

old motorhead

To the OP, I'm near Houston and have a pair of Z06 mufflers for sale. If you're interested, send me a PM.

L98IROCZ89

I think this is a matter of being clear.

Believe factory NPP like on a Z06 automatically went from mild to wild at a certain RPM, or you can install NPP In A Box to have control with the push of a button as to whether it is open or closed regardless of RPM.

Then there is a car that didn't come with factory NPP, these don't open and close at all unless you get NPP In A Box in which case you have control with a button.

TucoTom

Kenny go with long tube headers & x-pipe since you already have headers & cam.

Kenny2428

I do have longtubes and a x pipe.

saplumr

Don't buy into this "no drone" stuff. Any loud exhaust with the right/wrong mod combination has the real potential for drone. Once the offroad x is in place, pandoras box is open.

jim2527

2 different mufflers may help. Or 2 different length mufflers.