Exhaust Resonator Question - ZR-1 Net Registry Forums

Johnny5 · 02-26-2015

On my previous 1994 LT1 i deleted the resonator which gave a deeper rumble in the exhaust (sounded very nice). I was thinking of doing the same with my 91 ZR1. Doing this won't throw any codes will it? (the service manual says replacement of resonator assembly will require replacement of both mufflers) And has anyone tried this yet and kept the stock mufflers? How does it sound? I originally wanted to put a corsa on but I'm waiting to do my tuneup first....injectors, coil packs. wires, fuel filter and maybe the fuel pumps.

GOLDCYLON · 02-26-2015

Quote:

Originally Posted by Johnny5

On my previous 1994 LT1 i deleted the resonator which gave a deeper rumble in the exhaust (sounded very nice). I was thinking of doing the same with my 91 ZR1. Doing this won't throw any codes will it? (the service manual says replacement of resonator assembly will require replacement of both mufflers) And has anyone tried this yet and kept the stock mufflers? How does it sound? I originally wanted to put a corsa on but I'm waiting to do my tuneup first....injectors, coil packs. wires, fuel filter and maybe the fuel pumps.

No it wont throw any codes a lot of folks have went to x pipes and switched out the exhaust as well. However you will pick a resonance issue between 1200-1800 RPMs.

I also a spare Corsa resonator if your interested.

KILLSHOTS · 02-26-2015

That was my "STEP 1". I didn't notice any difference. I'm in the minority, though, as a couple of other guys have done the same thing and really liked the extra rumble. My advice: remove the resonator AND the mufflers...it sounds amazing!

WARP TEN · 02-26-2015

Goldcylon is right. The ZR-1 engine has pronounced natural resonance at two rpm points, about 1800 and about 3400. I believe he is right that the center resonator handles the 1800 rpm frequency and the mufflers handle the 3400 rpm frequency, although it might be the reverse; can't remember. Both contain what are known as Helmholtz Resonators, essentially empty containers specifically sized to damp down the resonant frequencies at those rpm points. Deleting the stock 91 resonator should provide a modest performance gain as the early resonators were quite restrictive. See Marc Haibeck's website to more on that.--Bob

Okiedoke · 11-13-2015

Quote:

Originally Posted by WARP TEN

Goldcylon is right. The ZR-1 engine has pronounced natural resonance at two rpm points, about 1800 and about 3400.

Well, that certainly helps explain things. I've been getting these annoying vibrations (okay, maddening vibrations) near these RPMs and my mechanic tracked it down to a busted resonator. So now I need to look for a replacement.

Johnny5 · 02-26-2015

Quote:

Originally Posted by GOLDCYLON

No it wont throw any codes a lot of folks have went to x pipes and switched out the exhaust as well. However you will pick a resonance issue between 1200-1800 RPMs.

I also a spare Corsa resonator if your interested.

How much did you want for it? And whats the difference if i just get meineke to weld an x pipe?

Johnny5 · 02-26-2015

Depending on the price welding thr nex x pipe or resonator i may just buy a used corsa or new obx after i fix my fuel issue. I want it to have a nice deep rumble but not too loud. I love the way my brothers 04 Z06 sounds (stock titanium mufflers).

GOLDCYLON · 02-26-2015

Quote:

Originally Posted by Johnny5

How much did you want for it? And whats the difference if i just get meineke to weld an x pipe?

PM Sent. The difference is you will pick up significant resonance and your exhaust will be louder. The CORSA resionator flows better than stock and you wont have the resonance issue.

Okiedoke · 11-13-2015

Quote:

Originally Posted by GOLDCYLON

PM Sent. The difference is you will pick up significant resonance and your exhaust will be louder. The CORSA resionator flows better than stock and you wont have the resonance issue.

Goldcylon, do you have the model number of this CORSA resonator? Would it adversely impact smog tests? Do you know if it's still possible to purchase a stock resonator?

WARP TEN · 11-14-2015

Quote:

Originally Posted by Okiedoke

Goldcylon, do you have the model number of this CORSA resonator? Would it adversely impact smog tests? Do you know if it's still possible to purchase a stock resonator?

The Corsa resonator would not adversely impact smog tests although visually it is slightly different from the stock one. Lee (LGAFF) has a used Corsa system for sale listed in the parts for sale section. --BOb

02-26-2015	#1
Johnny5 Join Date: Nov 2014 Location: New Jersey Posts: 363	Exhaust Resonator Question On my previous 1994 LT1 i deleted the resonator which gave a deeper rumble in the exhaust (sounded very nice). I was thinking of doing the same with my 91 ZR1. Doing this won't throw any codes will it? (the service manual says replacement of resonator assembly will require replacement of both mufflers) And has anyone tried this yet and kept the stock mufflers? How does it sound? I originally wanted to put a corsa on but I'm waiting to do my tuneup first....injectors, coil packs. wires, fuel filter and maybe the fuel pumps. Last edited by Johnny5; 02-26-2015 at 08:25 AM.

02-26-2015	#3
KILLSHOTS Join Date: Feb 2014 Location: AZ Posts: 857	Re: Exhaust Resonator Question That was my "STEP 1". I didn't notice any difference. I'm in the minority, though, as a couple of other guys have done the same thing and really liked the extra rumble. My advice: remove the resonator AND the mufflers...it sounds amazing!

02-26-2015	#4
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,151	Re: Exhaust Resonator Question Goldcylon is right. The ZR-1 engine has pronounced natural resonance at two rpm points, about 1800 and about 3400. I believe he is right that the center resonator handles the 1800 rpm frequency and the mufflers handle the 3400 rpm frequency, although it might be the reverse; can't remember. Both contain what are known as Helmholtz Resonators, essentially empty containers specifically sized to damp down the resonant frequencies at those rpm points. Deleting the stock 91 resonator should provide a modest performance gain as the early resonators were quite restrictive. See Marc Haibeck's website to more on that.--Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough" Last edited by WARP TEN; 02-26-2015 at 10:55 AM.

02-26-2015	#7
Johnny5 Join Date: Nov 2014 Location: New Jersey Posts: 363	Re: Exhaust Resonator Question Depending on the price welding thr nex x pipe or resonator i may just buy a used corsa or new obx after i fix my fuel issue. I want it to have a nice deep rumble but not too loud. I love the way my brothers 04 Z06 sounds (stock titanium mufflers). Last edited by Johnny5; 02-26-2015 at 11:38 AM.