Exhaust issues

[SurfnSun]

Now that I am firmly commited to buying a Callaway I am interested in building the best exhaust possible for the car. My ONE and only hang up is that it must have near zero resonance. My old 85 with 2.75" Borlas and no cat was almost impossible to drive. I am thinking of a dual exhaust all the way back trying X and H pipe to lower resonance. A chick that works with me has a husband who owns a muffler shop so I can get experimental with out incurring large costs. Any one have ideas?

Lou, how is the resonance on your car?

 

[*89x2*]

The turbo's really cancel out resonance... I cannot recall any like I have w/ my other vette... Now I will say you MUST hear an 87's Megaphones as I will be buying some (at some point) for my car
Later, *89x2*

 

[90Callaway]

It will still be loud...

I pretty much agree. The turbos do cancel out some of the noise you'd expect from a really free flowing exhaust. I must say that even so my car is pretty darn loud with the Magnaflow mufflers I put on last year. It currently has a single 3" pipe down the middle (no cat) but I do plan to go true dual with an X pipe at some point in the future. Maybe Josh can be the pioneer on that one and send us all pics!

 

[*89x2*]

87's w/ the Megaphones

I have heard 2 different 87's w/ the Callaway Megaphones installed on the 87's, stock... One w/ cats, one w/ out...
The onw w/ cats was raspy and tough but not intrusive The other 87 w/out the cats was NASTY!!!!!!! one of the meanest and baddest cars I have EVER heard but no resonance
I anxiously await Josh's purchase so he can do a Dr. Jekle/Mr. Hyde on it

 

[TAC]

Re: 87's w/ the Megaphones

I have heard 2 different 87's w/ the Callaway Megaphones installed on the 87's, stock... One w/ cats, one w/ out...
The onw w/ cats was raspy and tough but not intrusive The other 87 w/out the cats was NASTY!!!!!!! one of the meanest and baddest cars I have EVER heard but no resonance
I anxiously await Josh's purchase so he can do a Dr. Jekle/Mr. Hyde on it

Mine has no precats, Random Tech hi-flow cat, no mufflers and megaphones. The sound is loud and gutteral at low revs and downright mean at 2200 and up. I literally never listen to the stereo in that car. I do have resonance at 1700 rpm exactly. It's only there when I am cruising and slowly hit that rev. When accelerating briskly, I don't hear any resonance. It's like a dentist drill going through my bones, though, when it does hit.

 

[SurfnSun]

Resonance at cruising speed is my main concern. I ruined my 85 when I gutted the cat, and put the Borlas on. I literally couldn't drive the car anymore it was so loud. That was one of the main reasons I was considering a C5.

I feel that 4+3s will always have more resonance due to the automatic nature of the tranny vs a 6speed.

I will probably try Flowmasters on the car, I heard a Callaway w/ them one time and it was probably the sweetest sounding Vette Ive ever heard. Plus they don't have the reputation for resonance that the Borlas do, and they're cheaper to boot.

I idea for the system is dual 2.75" or 3" with an x or h pipe where the main cat sits now and possibly a balance tube running between the rear sections across the spare tire area, kinda like the Dynomax rear Y pipe. Hopefully that won't be necessary though. I think that maybe having duals all the way back may help the resonance issue b/c there won't be any bottle-necking and then breaking into the rear Y. I could be way off on that, though.

As you can see Ive put alot of thought into this. Hopefully we'll find success and I won't have to wear earplugs or consume an entire bottle of advil on the trip to Carslile

 

[*89x2*]

Hopefully we'll find success and I won't have to wear earplugs or consume an entire bottle of advil on the trip to Carslile

Does this mean you have decided upon a Callaway?? Which one r u getting???

 

[SurfnSun]

Im waiting to the end of the auction before I move.

 

[TurboLuigi]

Gee.... My 91 has a stock exhaust (I'm pretty sure) with Callaway stamped tips and it is extremely quiet. People who haven't looked under the hood think its a stock car with a body kit until the pedal hits the metal and they are looking at my rear end, and the stereo sounds great through the whole RPM range. Obviously there is more noise at 4-5K RPM but it's not uncomfortable and much quieter than my GNX.

Luigi

 

[SurfnSun]

Gee.... My 91 has a stock exhaust (I'm pretty sure) with Callaway stamped tips and it is extremely quiet. People who haven't looked under the hood think its a stock car with a body kit until the pedal hits the metal and they are looking at my rear end, and the stereo sounds great through the whole RPM range. Obviously there is more noise at 4-5K RPM but it's not uncomfortable and much quieter than my GNX.

Luigi

The key word there being "stock." As Im sure you know, there is massive power potential to be gained from large exhaust on turbo cars. Which is why we see all the ricer crap. My goal is to have a large free flowing exhaust for Callaway TT's that doesn't make someone sorry to drive the car.