1994 Mufflers

[jeasen]

I want to upgrade the exhaust on my 1994 ZR1. My first thought was Corsa, but after reading a report on the 1994 exhaust system by Haibeck Automotive it appears that the bottle neck in the 1994 factory exhaust is the mufflers. Only 1 psi difference across the cats, no difference in pressure across the resonator, but 4 psi increase in front of the mufflers. A Corsa system would not do anything for the difference in pressure across the cats, and there is nothing wrong with the resonator. So maybe just a muffler change??

Anyone know of a non restrictive replacement muffler for the 1994 ZR1? It appears the the diameter of the pipes leading to the factory muffler is 2 3/4". The LT1 mufflers are 2 1/2" or 2 1/4" and would be no improvement over the stock ZR1 mufflers.

There is nothing wrong with my exhaust system I just want to add a little more performance.

I guess I could just remove the mufflers and replace them with a straight pipe but I am concerned about the noise that would make?

Anyone have any suggestions or thoughts on this?

[jonszr1]

you might go look on the corvette action center , and see what hib halverson put on for mufflers. i believe they were 3 chamber flowmasters

[Kb7tif]

I want to upgrade the exhaust on my 1994 ZR1. My first thought was Corsa, but after reading a report on the 1994 exhaust system by Haibeck Automotive it appears that the bottle neck in the 1994 factory exhaust is the mufflers. Only 1 psi difference across the cats, no difference in pressure across the resonator, but 4 psi increase in front of the mufflers. A Corsa system would not do anything for the difference in pressure across the cats, and there is nothing wrong with the resonator. So maybe just a muffler change??

Anyone know of a non restrictive replacement muffler for the 1994 ZR1? It appears the the diameter of the pipes leading to the factory muffler is 2 3/4". The LT1 mufflers are 2 1/2" or 2 1/4" and would be no improvement over the stock ZR1 mufflers.

There is nothing wrong with my exhaust system I just want to add a little more performance.

I guess I could just remove the mufflers and replace them with a straight pipe but I am concerned about the noise that would make?

Anyone have any suggestions or thoughts on this?

Headers. You will like them. A bit loud though.

[secondchance]

I don't know whether it's the muffler design or the pinching of pipe as it connects to the factory muffler.
I personally like the 92 and later factory muffler tips. I think Corvette Central carries Magnaflow mufflers and it looks like it retains factory style tips (a wide black rectangular tip).
Does anyone had experience with Mangaflo?

[ZZZZZR1]

Headers. You will like them. A bit loud though.

Negative.... That is the sound that an LT5 should sound like!


:)


David

[1990 415]

Definitely go with headers and straight pipe. I have this on both of my ZR-1s and it sounds awesome. Straight pipe gives the sound of a serious performance sports car.

[902066]

Definitely go with headers and straight pipe. I have this on both of my ZR-1s and it sounds awesome. Straight pipe gives the sound of a serious performance sports car.
Lets here a sound clipp of one of your cars, for those of us thinking of going this route. Please

[Jeffvette]

Lets here a sound clipp of one of your cars, for those of us thinking of going this route. Please


You'll have to show up at BG, he is internet impaired.

[32valvZ]

I want to upgrade the exhaust on my 1994 ZR1. My first thought was Corsa, but after reading a report on the 1994 exhaust system by Haibeck Automotive it appears that the bottle neck in the 1994 factory exhaust is the mufflers. Only 1 psi difference across the cats, no difference in pressure across the resonator, but 4 psi increase in front of the mufflers. A Corsa system would not do anything for the difference in pressure across the cats, and there is nothing wrong with the resonator. So maybe just a muffler change??

Anyone know of a non restrictive replacement muffler for the 1994 ZR1? It appears the the diameter of the pipes leading to the factory muffler is 2 3/4". The LT1 mufflers are 2 1/2" or 2 1/4" and would be no improvement over the stock ZR1 mufflers.

There is nothing wrong with my exhaust system I just want to add a little more performance.

I guess I could just remove the mufflers and replace them with a straight pipe but I am concerned about the noise that would make?

Anyone have any suggestions or thoughts on this?

You will never notice a performance difference by changing mufflers on any car. Sound difference, yes, but not a noticeable SOTP feel. Listen to us and bolt on some headers and then a nice Corsa or B&B cat back system. Youll have performance along with the sound improvment.
:cheers:

[1990 415]

You'll have to show up at BG, he is internet impaired.

I take that personally - even if it is true:dancing

I will have my 415 with straight pipes at BG in May. I'll be glad to give you an earfull. I detest mufflers on a ZR-1.:thumbsup:

[902066]

I take that personally - even if it is true:dancing

I will have my 415 with straight pipes at BG in May. I'll be glad to give you an earfull. I detest mufflers on a ZR-1.:thumbsup:



For all the reasons to go to BG, this might be the best one for me.

[jonszr1]

You will never notice a performance difference by changing mufflers on any car. Sound difference, yes, but not a noticeable SOTP feel. Listen to us and bolt on some headers and then a nice Corsa or B&B cat back system. Youll have performance along with the sound improvment.
:cheers:cont rary to what was said before you can get a performance increase by changing mufflers .hib got a 18 hp increase by going to a 3 in 3 chamber flowmaster muffler , i got a similar increase by going to a custom dr gas 21/2 in system from the flowmaster system

[jeasen]

Happy Thanksgiving everyone. Thanks for replying to my post.

It looks like there are several opinions when it comes to answering my question.

At this point it appears that a 3" straight pipe in place of the mufflers is the best answer. If I cannot stand the noise then I can deal with that later.

Any other opinions or comments out there?
Jeasen

[Aurora40]

Happy Thanksgiving everyone. Thanks for replying to my post.

It looks like there are several opinions when it comes to answering my question.

At this point it appears that a 3" straight pipe in place of the mufflers is the best answer. If I cannot stand the noise then I can deal with that later.

Any other opinions or comments out there?
Jeasen
I had basically what you are talking about. Stock pipes, LT4 resonator (the '90-91 resonator is much smaller than yours), and Dynomax 3" Ultraflow mufflers.

With stock manifolds it sounded really good, but there was definitely more resonance than stock. With headers it sounded REALLY good, but there was a ton of resonance. I got sick of putting earplugs in for any longer drives, and in winter with the windows up, so now I sport Corsa's.

I'd say maybe try a 2.5" muffler vs 3". Maybe it will cut down on the resonance some more.

[jonszr1]

in messing around today with my blk car ,i found that i cut a ton of resonance out of the car by extending the tips after the mufflers 4 in beyond the rear valance . i could believe how much quieter it5 got inside the car, some may not like that look and i totally understand ,butr my old 57 yr old ears just needed some peace and i dint want to give up the performance gains that my dr gas exhaust had given me , by the way its a 21/2in exhaust with an xpipe . the idea came from a muffler guy who is spending the week with us . he also thought that if we cut a resonator in half and gut it then cut openingsso that it fit over the x pipe fill it with steel wool that it might really also quiet things down . he says the resonance comes from in part due to the pipes vibrating at a certain rpms.dont know if hes right but it kinda makes some sence , and what the heck i thought its worth a try . .hope every one has a great t day:thumbsup:

[Hammer]

This is my '91 #473 with Watson 1 7/8" Headers, no cats and the standard Flowmaster Cat Back Exhaust System, I think it's #17115 or something like that (Thanks Ryan and Kevin).

http://static.photobucket.com/player.swf?file=http://vid85.photobucket.com/albums/k60/HammerZR1/ZR-1%20No%20473/100_1758.flv

http://static.photobucket.com/player.swf?file=http://vid85.photobucket.com/albums/k60/HammerZR1/ZR-1%20No%20473/100_1759.flv

[tomtom72]

I like those muffler tips. I think they look cool!:thumbsup:

It doesn't sound overly loud either. How's is the resonance?

[Hammer]

I like those muffler tips. I think they look cool!:thumbsup:

It doesn't sound overly loud either. How's is the resonance?

There isn't any resonance pre se', nothing like the B&B. You get a little, way down low, around 1200 to 1400 or so. This system never rattles you out of the car like the others. PLus if you look around, I think you get a Flowmaster for around $800 or less shipped.

[HAWAIIZR-1]

There isn't any resonance pre se', nothing like the B&B. You get a little, way down low, around 1200 to 1400 or so. This system never rattles you out of the car like the others. PLus if you look around, I think you get a Flowmaster for around $800 or less shipped.


Sound great John, thanks for sharing.

[tomtom72]

:thumbsup: Thank you John for the reply!

I think I may have to investigate the flowmaster web site.

:o I just really like the look of the exit tips on your system, they kind of remind me of the Callaway exit tips. To me, the "oval" type exits just don't do it for me on a C4. I like the 90 stock tips, the LT1 tips, and the ones you have.

:cheers:
Tom

[Hammer]

There isn't any resonance pre se', nothing like the B&B. You get a little, way down low, around 1200 to 1400 or so. This system never rattles you out of the car like the others. PLus if you look around, I think you get a Flowmaster for around $800 or less shipped.

Actually this system at Summit Racing is $655.95 plus $15.00 oversize charge and $11.95 handling. So total of $682.90 to your door. Check Performance Peddler, they might have it cheaper. Pretty good value for a nice sounding exhaust. It's not stainless steel though, so get some of the high temp paint too. I used the Design Engineering paint from Summit and it has held up very well.

http://www.summitracing.com/parts/FLO-17115/
http://www.summitracing.com/parts/DEI-010301/
http://www.summitracing.com/parts/DEI-010302/

http://i85.photobucket.com/albums/k60/HammerZR1/ZR-1%20No%20473/100_0620.jpg?t=1259422003
http://i85.photobucket.com/albums/k60/HammerZR1/ZR-1%20No%20473/100_0625.jpg?t=1259422154
http://i85.photobucket.com/albums/k60/HammerZR1/ZR-1%20No%20473/100_1291.jpg?t=1259422207

[tomtom72]

John, that looks sweet. Was the OEM system made from a low percentage s/s alloy, or was it aluminum + steel?

While I was researching header coatings I ran across a vendor that said I should coat the entire exhaust system as it would maintain the heat content all the way down the line to the tips. It kind of made sense to me? I was thinking about the trouble I could have passing emission's tests with the way the hi flow cats don't stay hot enough at low load situations.

[Hammer]

John, that looks sweet. Was the OEM system made from a low percentage s/s alloy, or was it aluminum + steel?
Really can't say, maybe someone else will know.

While I was researching header coatings I ran across a vendor that said I should coat the entire exhaust system as it would maintain the heat content all the way down the line to the tips. It kind of made sense to me? I was thinking about the trouble I could have passing emission's tests with the way the hi flow cats don't stay hot enough at low load situations.
Coating the entire system would make sense, but I would think it would be VERY expensive. So I can understand why a vendor would want you to coat the system.

[mgbrv8]

That is one clean under carriage Hammer


Dave

[Hammer]

That is one clean under carriage Hammer

Dave

Thanks Dave,

As I think you already know, I try to keep a pretty clean car. Considering I don't have a lift :blahblah: I feel I do a pretty fair job. By the way, still waiting on pics of the painted car. I think everyone here would appreciate some shots of ol Bad *** #458. :rolleyes:

Been reading your posts and that drain hole idea is great.

[jeasen]

I am really glad I asked this question. There is some really great information that's been posted by other members of this board.

I just wanted to let everyone know what I found out about replacing the mufflers on my 1994 ZR1. I talked to tech support at Corvette Central and found out that the muffler eliminator pipes they sell for the 1992 - 1996 are 2 3/4" in diameter so they should match the diameter of the exhaust pipes on the ZR1. So this is an option for muffler replacement on my 1994, however, I am apprehensive because of the possible noise it will create due to eliminating the mufflers.

The tech guy said that all replacement mufflers for the later model C4 will have 2 3/4" diameter pipe. If I want mufflers he suggested their Magaflow replacement mufflers (Corvette Central part # 324337). He said that they were a straight thru design and have 2 3/4" diameter inlet pipe. The thing he could not tell me is if it would fit a ZR1. I am worried about the fit because the ZR1 is wider at the rear? Anyone have experience or thoughts on this?

I am going to check out a replacement muffler today by going to the local parts store and ordering one. If it looks like it will fit then maybe the Magaflows from Corvette Central is the way to go. The straight thru design should eliminate the bottle neck at the stock mufflers and maybe offer some quieting over the muffler eliminator pipes.

I will let you know what I find out. Jeasen

[jeasen]

Well I was unable to find out anything at the local parts store. Every muffler listed was a special order so I was not able to order one in to compare to my ZR1 muffler without paying for it along with the shipping.

I did find out that the listings for the regular C4 states "except ZR1" so that tells me that I should not order the Magaflow mufflers from Corvette Central. However, I was able to confirm that the later C4's do have a 2 3/4" diameter pipe which is the same as the ZR1.

My only hope is that someone here can answer my muffler question which is ("Does somebody make a free flowing muffler that will fit a 1994 ZR1?"). I still do not want to change the whole system is I can just change the mufflers.

Jeasen

[jonszr1]

did you take a look over on corvette action center and read what hib did . he fit 3 in flowmaster 3 chamber muffler to his system .a decent muffler shop should be able to do this for you . they could even transfer your tips for that stk look

[tccrab]

Well I was unable to find out anything at the local parts store. Every muffler listed was a special order so I was not able to order one in to compare to my ZR1 muffler without paying for it along with the shipping.

I did find out that the listings for the regular C4 states "except ZR1" so that tells me that I should not order the Magaflow mufflers from Corvette Central. However, I was able to confirm that the later C4's do have a 2 3/4" diameter pipe which is the same as the ZR1.

My only hope is that someone here can answer my muffler question which is ("Does somebody make a free flowing muffler that will fit a 1994 ZR1?"). I still do not want to change the whole system is I can just change the mufflers.

Jeasen

I have a set of used flowmaster mufflers that I'll sell you cheap.
Shipping will be probably be more than the mufflers (hah!!).

TomC
"Crabs"

[jeasen]

did you take a look over on corvette action center and read what hib did . he fit 3 in flowmaster 3 chamber muffler to his system .a decent muffler shop should be able to do this for you . they could even transfer your tips for that stk look

jonszr1, I looked and looked but could not find anything about what Hib did on the Corvette Action Center website. I am somewhat computer challenged but I am usually able to find my way around websites OK. If you know where to find it a link would be greatly appreciated. Thank you.

[jonszr1]

i am in the same boat as you but will see if i can find it for you

[jonszr1]

in fact the article is on our site . go to the main registry page and click on articles . when that comes up. on the left side of the page there is a list .click on articles again and you will find it under 38 hp gain .let me know if you cant find it

[jeasen]

jonszr1, thanks for your help. I found it.

Jeasen