Hey guys, I've come to notice that most of you on this site have catbacks such as Borla's and Corsa's and I'm just wondering how they compare in power/sound to a dual cut-out system (ex: QTEC).

The cutout is perhaps the most common mod on Fbody's (perhaps next to an air-lid), and I'm just wondering why it's not so popular on the Vettes.

I know the Vette catbacks typically offer very few extra ponies, but do cut-outs give any more?

One last question: I had a cutout on my old 98 Z28 w/ a Flowmaster axle-back exhaust and it sounded absolutely amazing. Wasn't raspy, just deep, loud and agressive. Will the same tone be obtained by installing a system such as the QTEC on a C5?

Thanks !!!

 

I love the way my cut outs sound and the 16.6 RWHP and 12.9 RWTQ don't hurt any . See my thread for pics http://forums.corvetteforum.com/showthread.php?t=914346

 

I have previously owned a 2000 SS, currently a 98 SS and a 99 C5. I've tried many different exhaust configurations so I'll try to answer your questions the best I can.

It's impossible to give you a definitive answer on power. It seems that different catbacks flow very, very different.

I have seen less than 10rwhp gain going from stock Z06 Tis to dual cutouts, on a nasty head/cam motor (~475rwhp).

But if you chose a poorly flowing catback system, cutouts would help immensely (I bet 15-20+rwhp on a heads/cam car).

Cutouts are less popular on C5s for a few main reasons. Corvette owners are generally older and don't like it to be that loud. Also requires 2 cutouts - twice the cost. It's also much tighter under a C5 - requires more work and creativity.



You can see my cutout installation. Very tight. The 2 motors are actually touching each other, and I had to modify one of them because it was hitting a rib on the tranny (the right one).


Anyway, you're not gonna duplicate F-body sound with your C5. No matter what I've done, I can't really even make it close. I had a single 3" cutout on my old modded 00 SS, and now I have dual 3" cutouts on my heavily modded 99 C5, and they sound worlds different. The f-body was much much deeper and nastier. The C5 still sounds great, but it's higher pitched and more...exotic.

I even used the same high flow cats and dynomax bullet race mufflers. The dual exhaust with X pipe just changes the tone too much I guess. I wish I could duplicate the sound of my old Camaro on my C5.

Dope

 

Thanks guys, I guess we can't have it all. I would have throught C5s can sound just like an Fbody, now I know they can't.

If you don't mind me asking, how much did it cost, all said and done, for the dual cutout job? Exhausts are ~1K, I'm figuring it must be slightly cheaper to do cutouts?

 

Cutouts are a nice mod for the C5 and give you more flexibility in how the car sounds. I spent ~$420 total, including fabrication, on my setup.

 

From what I have been reading, I am concluding that a stock exhaust + cutouts is pretty much as free flowing (if not more) than a catback system with no cut-outs, right?

 

I got around 200.00 in mine, but they are manual not electric.

 

Keep in mind, it will still sound really nasty. You can get it deeper/nastier by keeping an H pipe and not going to an X pipe.

Total alltogether? The cutouts were ~225 (McCord) and the fabrication work on everything (welding in the bullet mufflers, cutouts, and flanges and such) was about $300.

Dual cutouts, whether 2.5" or 3" will outflow any aftermarket catback, period.

Dope

 

This forum rocks, you can get basically any question answered! Thanks !!!!