Stock exhaust limits
Thread Starter
Instructor
Joined: Sep 2007
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From: Philadelphia PA
Stock exhaust limits
Sorry for the newbie question, but is the stock exhaust a limitation for tuning?
If you were doing all the typical bolt-ons- intake, headers, catted x-pipe, then possibly a cam and intake manifold, at what point is the stock exhaust a limitation?
The reason I ask is because from what I've read so far, getting long-tube headers makes the car quite a bit louder and I don't want to make the car so obnoxiously loud that I can't take a long road trip in the car, but I don't want the cat-back to be a limiting factor.
My ultimate goal is probably around 425-450rwhp with everything done on an LS2, so I'm not looking for crazy power gains.
If you were doing all the typical bolt-ons- intake, headers, catted x-pipe, then possibly a cam and intake manifold, at what point is the stock exhaust a limitation?
The reason I ask is because from what I've read so far, getting long-tube headers makes the car quite a bit louder and I don't want to make the car so obnoxiously loud that I can't take a long road trip in the car, but I don't want the cat-back to be a limiting factor.
My ultimate goal is probably around 425-450rwhp with everything done on an LS2, so I'm not looking for crazy power gains.
Team Owner
Joined: Mar 2005
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From: salem OR
Sorry for the newbie question, but is the stock exhaust a limitation for tuning?
If you were doing all the typical bolt-ons- intake, headers, catted x-pipe, then possibly a cam and intake manifold, at what point is the stock exhaust a limitation?
The reason I ask is because from what I've read so far, getting long-tube headers makes the car quite a bit louder and I don't want to make the car so obnoxiously loud that I can't take a long road trip in the car, but I don't want the cat-back to be a limiting factor.
My ultimate goal is probably around 425-450rwhp with everything done on an LS2, so I'm not looking for crazy power gains.
If you were doing all the typical bolt-ons- intake, headers, catted x-pipe, then possibly a cam and intake manifold, at what point is the stock exhaust a limitation?
The reason I ask is because from what I've read so far, getting long-tube headers makes the car quite a bit louder and I don't want to make the car so obnoxiously loud that I can't take a long road trip in the car, but I don't want the cat-back to be a limiting factor.
My ultimate goal is probably around 425-450rwhp with everything done on an LS2, so I'm not looking for crazy power gains.
thats why the Z0-6 mufflers or NPP is the thing to have. below is the difference between stock mufflers and z0-6
8 rwhp, 9 rwtq @ 4200 rpm equal to 10 or more at the crank you can feel em when there open!
Last edited by 3 Z06ZR1; Aug 17, 2008 at 02:42 PM.
Safety Car
Joined: Sep 2007
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From: Los Alamitos California
St. Jude Donor '09
The stock exhaust doesn't limit the stock motor or even the modded motor. The difference between the stock exhaust and cutouts was only 6whp. This has been discussed many times.
Pro
Joined: Apr 2008
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From: Scottsdale Arizona
I had headers and the stock exhaust. Its not loud at all. Sounds much better though. I now have the ZO6 exhaust on with the Bi-Mode set to open. Now its a little loud, but I can close it when I want.
Safety Car
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From: Los Alamitos California
St. Jude Donor '09
San
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Burning Brakes
Joined: Jan 2008
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From: BURTON MI
This is true, it's the header that so restrictive. The NPP only gives 6 hp, the header will give 25.(Headers and NPP will not give 31, more like 27-28) Several posters have claimed headers with stock ecxaust is not loud and has no drone. To get to 450 you will need headers, cai,cam,heads or a Fast, tune and you can keep the stock muflfler. Hope this gives OP some idea of what will be needed.
Melting Slicks
Joined: May 2004
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I have stock exhaust (catback) and headers. I think the car sounds just right, especially if you want to do long highway cruises. I tried a set of B&B Rt 66 touring. The car sounded great around town, but was a bit loud for the long cruise. If it were just a around town cruiser, I would have kept them, but since the car does double duty, I took them off. Do your bolt ons, you can always add catback later if its not loud enough, and you want that extra 6-10hp.
Team Owner
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From: salem OR
the proof is in my post don't care who said what here.
Safety Car
Joined: Sep 2007
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From: Los Alamitos California
St. Jude Donor '09
So your post showed 8rwhp versus 6rwhp with cutouts. Even if your results were definitive, you think this proves the stock exhaust is limiting? The OP didn't ask if gains could be made over the stock exhaust, rather, was it limiting. It isn't.
San
San
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From: Los Alamitos California
St. Jude Donor '09
Check this thread to see how "limiting" the stock exhaust is. This is with cats as well.
http://forums.corvetteforum.com/show...ght=bowmanized
San
http://forums.corvetteforum.com/show...ght=bowmanized
San
Team Owner
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From: salem OR
It limit's the power very clearly, whats not to like, this is not open vs closed. this is the stock c-6 mufflers vs the Z0-6 mufflers open with no controller.8 rwhp 9 rwtq is limited from the power output @4200 Even with being tuned for the stock cans. Power difference is very plain. his 500 would be 520plus easywithout the limiting factor of the stock catback. sheezzz
Last edited by 3 Z06ZR1; Aug 17, 2008 at 03:25 PM.
Safety Car
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From: Los Alamitos California
St. Jude Donor '09
The OP also said he didn't want the car obnoxiously loud, which is a matter of opinion. I personally would give up the 8rwhp (if it's even that much) for a quieter car. Face it, the major power adder is not the exhaust.
San
San
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From: salem OR
lousy exhaust limit's the motor's output, even more when you change the cam and heads. Thats why the exhaust controller is so nice,
Close it and it's nice quite!
Thread Starter
Instructor
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From: Philadelphia PA
except it's THE power adder when you include headers which is part of the exhaust, from engine to muffer tip, it's all the exhaust system.
lousy exhaust limit's the motor's output, even more when you change the cam and heads. Thats why the exhaust controller is so nice,
Close it and it's nice quite!
lousy exhaust limit's the motor's output, even more when you change the cam and heads. Thats why the exhaust controller is so nice,
Close it and it's nice quite!
Safety Car
Joined: Sep 2007
Posts: 4,359
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From: Los Alamitos California
St. Jude Donor '09
My real question I guess is what is the limit of what can be done before the stock exhaust becomes a limiting factor? I'm not talking about 3 or even 5 hp, but where you start doing mods and not seeing results because the stock exhaust simply can't flow enough. I'm trying to prioritize my bolt-on budget- if headers is where it's at, then I'm doing the LT headers before anything else. That's what I'm getting at. Thanks.
I would also question how much ANY exhaust adds. There have been many discussions, but it is generally agreed that the difference between stock exhaust and NO exhaust is ~6rwhp. I've seen SPIN post this but I don't remember who exactly did the dyno testing. It was someone with cutouts.
For your situation I would go with headers and leave the stock exhaust intact. One poster here said he went to the Z06 exhaust and it's a bit loud now. I just replaced a loud exhaust with a quiet one on my other car and I will be very cautious with the Vette. It looks fast sitting still, so I don't need any additional attention from LEOs.
San
Team Owner
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From: Long Island New York
As stated already,headers make the car sound sound like a Corvette and not an Impala like it does with the stock exhaust. Headers give the perfect ump when you put your foot down even with the stock mufflers. Others may like it louder but Im happy with the long tubes.
