95jersey

I figure instead of shilling out $1500 for some cheesy cat back system that is too loud for the street and not loud enough for the track, it seems like the old fashioned "cut out" solution would be perfect for me.

For the street I like the quietness of the stock exhaust, but at the track I miss the sound/power/throttle response of an open exhaust. I would not be happy with some mediocre Corsa exhaust and I was sick of the loud abuse of my open exhaust on the street.

It seems like putting a simple manual cut out after the cats, but before the muffler would be the perfect solution for some extra sound and power for the track.

Anyone have these on their car? Any drawbacks? My only concern would be the raw heat from the exhaust blowing basically right on the transmission/rear. I spoke with my local muffler guy and he is saying they could probably make some turn downs to direct the exhaust toward the ground.

Any thoughts? Real world advice?

stairman

watch out for melting your rear spring, it happens a lot with cut outs blowing direct heat on it.

NoOne

I melted my rear spring, now have downturns.

If you want the "loudest car at the track award" then get them

It makes it easy for people to find me on the track, car screams. I have QTP long tubes, no cats and their H with the built in cut outs.

Only con is they sound cool at idle but anything less than WOT they sound muddled. With an X pipe you might do better for sound.

However at WOT I'm told the car sounds amazing going down the straights.

gkmccready

Removing the exhaust restrictions wouldn't you need a different tune in the computer?

95jersey

Where did you get the turn downs? Did your shop make them?

I just like the sound of a loud motor at the track. I can actually hear my revs match during heel/toe. What's attractive is that I can switch back and forth.

Regarding the tune, you wouldn't NEED a tune. You would probably gain a few more HP if you have one, but who cares. For $100 bucks it looks like a great exhaust mod for the track.

Thanks for the advice about melting the spring. I never even thought of that...

great F'n forum man!

xsiveone

I've seen those electric cutouts dump right back by the rear diff. Not a good idea IMO. If the car runs well enough (not needing a tune) with the exhaust open, I don't see a problem unless the cutouts dump right on a critical part of the car that can't take the heat (springs, rear diff, etc).

NoOne

I have electric cut outs, just had the local shop make me down turns.

Its not hard, a flange, a 90 degree turn, cut it level. Weld the two together and bolt on.

I'd really go with electrics...its a PITA to get under the car to open them up.

You generally get more HP, less torque, maybe a 2-5 percent loss in torque and the same amount of rise in HP.

To me a lack of torque in some places at the track isn't a bad idea.

95jersey

I looked under the car today and there isn't much room. I have a C6Z06 with 3" pipes and it's fairly tight. Do any of you guys have pics?

XPC5R

The C6 is a better candidate to build the cutout at the rear muffler area, or just have the rear mufflers removable , using nice v-band clamps for track days.

Also consider a magnaflow or borla muffling setup. Those steel/ceramic packed mufflers are much more mellow and refined sounding around town at low loads, but will bark nicely due to the free flow design at WOT. There is a reason so many street rods and hot rods use them in the builds - just listen to any of the overhaulin builds start up. Corsa's and others that just use chambers always end up a little less impressive as they leave too manyy high frequencies.

I take it the factory dual mode mufflers are not loud enough

95jersey

I will never if maybe once have them off on the street. The car is 85% track duty. I like the sound of my last car with open exhaust and pair of stingers, but it was too loud on the street. The C6Z is too nice of a car to put open pipes and drive around town. On the other hand at the track, I don't care about resonating frequencies and refined sounds at low loads. Just looking for raw sound and some extra power/throttle response.

xsiveone

That's the con. From what I've seen, there's really no good place to dump them out IMO. Maybe someone here will surprise us though.

GT40_GearHead

there is a dude that put electric cut outs on his C4, but he welded back pipes to the cut outs to get the exhaust out from under the car.

i'l go find his post....

EDIT: here ya' go : pics and thread

BrianCunningham

I run muffler eliminators, basically replaced the mufflers with straight pipes. It's not as loud as you think since I'm running the cats.

With cutouts, you should have two fuel maps with and w/o the mufflers, but since you can't you'll need to have it remapped w/o and then just run in not optimized with the mufflers.

jpobrien

Without the restriction of the mufflers, the engine will move more air. Without changing the tune, the fuel/air mixture will run lean, which will lead to higher combustion temperatures. Rich mixture is safe.