Interesting Exhaust design

[-=Jeff=-]

I know this is not a LT5 but a LS conversion.

I thought this exhaust was interesting..2 X pipes.. Wonder how is sounds
https://scontent.xx.fbcdn.net/v/t1.0-9/13627095_1177314168957610_7207497168600785306_n.jp g?oh=1eb08c44365dc0d8f13df43644e88837&oe=582E7597

[KILLSHOTS]

Probably similar to the Corsa Double Helix X-pipe I have on my Stingray. Compared to a single X, this is supposed to smooth out the sound...more European and less muscle car is the stated concept.

http://www.corsaperformance.com/images/config/zoom/1464/1464a.jpg

[-=Jeff=-]

Chris,

did you notice a difference when it was installed vs OEM on your Stingray?

Granted I know the newer vettes don't have the same resonance issue as the C4.. I truly wonder if it helps to mitigate resonance. Also curious on the sound.. that set up gives me ideas.. not that I am going to swap what I have

[GOLDCYLON]

Chris,

did you notice a difference when it was installed vs OEM on your Stingray?

Granted I know the newer vettes don't have the same resonance issue as the C4.. I truly wonder if it helps to mitigate resonance. Also curious on the sound.. that set up gives me ideas.. not that I am going to swap what I have

Since he's not using mufflers in that set up it has to be to mitigate resonance sound.

[KILLSHOTS]

Chris,

did you notice a difference when it was installed vs OEM on your Stingray?

Granted I know the newer vettes don't have the same resonance issue as the C4.. I truly wonder if it helps to mitigate resonance. Also curious on the sound.. that set up gives me ideas.. not that I am going to swap what I have
Hey Jeff,

Yes, I sure did, BUT to be fair, I can't really tell you what effect the pipe itself had, because I had it installed along with headers and a cat-back. Unfortunately, the only thing I can really tell you is that guys were saying the double X had less popping on decel than the single X from Borla, and there is definitely almost none, so that's one effect that I can verify. Sorry I can't help more.

[32valvesftw]

I may need to try something like that as my single X pipe setup DROOOOOOOOONES

[5ABI VT]

Its a cool design I have the double on my corsa on my 15 mustang :-D

[WARP TEN]

I know this is not a LT5 but a LS conversion.

I thought this exhaust was interesting..2 X pipes.. Wonder how is sounds
https://scontent.xx.fbcdn.net/v/t1.0-9/13627095_1177314168957610_7207497168600785306_n.jp g?oh=1eb08c44365dc0d8f13df43644e88837&oe=582E7597

Looks like no mufflers to speak of; essentially straight pipes. So it is likely to be very loud and have substantial drone at 1800 and 3400 rpms. The double X pipe does not reduce resonance but as noted may smooth the sound a little as it helps combine the individual engine pulses. --Bob

[-=Jeff=-]

Looks like no mufflers to speak of; essentially straight pipes. So it is likely to be very loud and have substantial drone at 1800 and 3400 rpms. The double X pipe does not reduce resonance but as noted may smooth the sound a little as it helps combine the individual engine pulses. --Bob

So you had this system on your car and you know it does not reduce drone?

Resonance is an interesting thing I have to wonder, if you used that design with some muffler between and then real muffler at the end.. would there be drone?

[WARP TEN]

So you had this system on your car and you know it does not reduce drone?

Resonance is an interesting thing I have to wonder, if you used that design with some muffler between and then real muffler at the end.. would there be drone?

No, Jeff, I did not have this system on either of my cars. But over the course of 20 years with ZR-1s I experimented with and tested about a half dozen exhaust systems, worked with an acoustics engineer to dissect and analyze the problem of resonance on our ZR-1s, and evaluated which systems can reduce it and why. The "droning" that everyone refers to is essentially two resonance peaks that occur naturally at roughly 1,800 and 3,400 rpms on LT5s and other Corvette V8s. When the engine is placed under load at these rpm points one gets fairly intense "droning" unless it is mitigated. About the only way to reduce this resonance is to utilize Helmholtz resonators in the mufflers and resonator as the stock and Corsa systems do. They are specifically designed chambers in which sound waves of the "drone" frequencies cancel each other out. Since I did not see any mufflers in the pictured system that appear large enough to accommodate them, I assumed that they are not in this system and therefore "drone" is likely. I could be wrong, though. Mufflers alone (i.e., without Helmholtz resonators) do not normally reduced resonance.--Bob

[-=Jeff=-]

Thanks for the info.. Unlike many, you DID research. Helps to put the research to back suggestion of drone.

I think I will keep my corsa system as is

[WARP TEN]

Thanks for the info.. Unlike many, you DID research. Helps to put the research to back suggestion of drone.

I think I will keep my corsa system as is

Your Corsa system is a good choice. Not to everyone's taste, but I always thought it had a great sound and I knew from my research that Corsa and stock systems (at the time anyway) were the only ones that used the Helmholtz resonators to eliminate resonance. Marc H says they tend to produce the most power of the various exhausts he has dynoed. Had Corsa's on both my Z's for most of the time I owned them. I even went out to the Corsa factory quite a few years ago and met with the owners once (when they were thinking of selling the company; they didn't then). Had a great tour, learned a lot about their approach to resonance mitigation and had a ride in Jim Browning's Cadillac with an experimental (at the time) Corsa exhaust. They were also building Viper exhausts for the factory. Fun. --Bob