[Z06] Exhaust question
Thread Starter
Cruising
Joined: Sep 2014
Posts: 14
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From: Fort Wayne Indiana
Exhaust question
New to the corvette scene, not sure if this is an issue that everyone else has with no cats or not. I have a very strong exhaust smell, clothes actually smell after I've been in it for any length of time. I've checked all connections, no leaks anywhere. Is this common, and what are my options for reducing or eliminating the smell?
I thought about adding high flow cats and an x pipe, to help eliminate the fumes. Currently have tsp long tube race headers, and off road straight pipes connected to corsa extreme exhaust, which I've been told I'd have to replace with headers made for cats, not sure what to do? The car is in need of a good tune though, but I doubt that will eliminate the odor?
I thought about adding high flow cats and an x pipe, to help eliminate the fumes. Currently have tsp long tube race headers, and off road straight pipes connected to corsa extreme exhaust, which I've been told I'd have to replace with headers made for cats, not sure what to do? The car is in need of a good tune though, but I doubt that will eliminate the odor?
Le Mans Master
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From: Was New Orleans but swam to Baton Rouge LA
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Are you sure it is the exhaust and not maybe a valve cover breather someone put on? I have headers and a lot of work done to my car. The only thing I have ever had smell inside the car was a valve cover breather when I had one.
Race Director
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From: Pasco WA
Get it tuned, first. If this isn't effective, then a new, catted X center section will help. Does your car have the factory cam? Positive overlap cams (aftermarket) make a huge difference in exhaust smell.
Thread Starter
Cruising
Joined: Sep 2014
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From: Fort Wayne Indiana
I'm not sure it's the exhaust, but I've been told by numerous people that it's because I don't have cats. I'll definitely check the valve cover breathers out though. Thanks for the advice.
Thread Starter
Cruising
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From: Fort Wayne Indiana
It has an aftermarket cam, pretty healthy one at that. The specs are 236/238, .601/.606, 113 LSA. I didn't want to get it tuned if if I'm going to have to install different headers and cats with x pipe. I would have to have it tuned again.
Le Mans Master
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From: Was New Orleans but swam to Baton Rouge LA
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With a cam like that I would probably look at the tune first. Even if you change headers and exhaust the tune would be close. The tune you have now is it stock, or setup for the cam? If you went from stock exhaust to the headers with that cam you definitely need it tuned. Tuning will clean up a lot of the smell. You will still have some from that cam's overlap, but it should not be inside the car unless you are stopped with a tailwind and the window down.
Race Director
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From: Pasco WA
Thread Starter
Cruising
Joined: Sep 2014
Posts: 14
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From: Fort Wayne Indiana
It has been tuned for the cam. The previous owner actually had it de-tuned a little because he was going to add nitrous. So you think I should still try a good tune before thinking of any exhaust work?
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Le Mans Master
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From: Was New Orleans but swam to Baton Rouge LA
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What exhaust do you have now? I think it would help. The nitrous de tuning would have timing reduced by around 2 degrees per 50 hp of nitrous. If it has a nitrous tune the car should be a dog with not all the power it could have.
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get the tune looked at but don't expect it to totally disappear... with a modded car you're gonna get the raw gas smell period... I happen to like it but if you don't you can always get a prius
Thread Starter
Cruising
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From: Fort Wayne Indiana
It has corsa extreme exhaust. It sure doesn't feel like a dog, at all!
Thread Starter
Cruising
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From: Fort Wayne Indiana
I didn't think it would completely disappear, unless I had cats put in. Just want my clothes to not smell like a race track when I'm on a date! Lol
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I have xtremes too but I don't really think the brand of exhaust matters... I'm also cammed, no cats, my tune is done right, etc, and it does smell real strong from the rear of the car but I don't really notice it inside the car... I can smell it slightly if I have the windows down sitting at a light but I don't think it's enough to make me and my clothes smell like gas... I could be less sensitive to it than some others but I haven't had anyone else complain about me smelling like gas either haha... do you happen to have a wideband in the car?
Le Mans Master
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From: Was New Orleans but swam to Baton Rouge LA
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I have xtremes too but I don't really think the brand of exhaust matters... I'm also cammed, no cats, my tune is done right, etc, and it does smell real strong from the rear of the car but I don't really notice it inside the car... I can smell it slightly if I have the windows down sitting at a light but I don't think it's enough to make me and my clothes smell like gas... I could be less sensitive to it than some others but I haven't had anyone else complain about me smelling like gas either haha... do you happen to have a wideband in the car?
My car is the same way. You can smell it from behind or at a light, typically if there is a tail wind. Inside the car you get nothing. The only time I had a smell inside my car was when I had a valve cover breather. For some reason that breather let out fumes when I was idling and they would be sucked into the car by the AC. The outside air intake for the AC is right at the back of the hood and below the wipers.
Thread Starter
Cruising
Joined: Sep 2014
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From: Fort Wayne Indiana
My car is the same way. You can smell it from behind or at a light, typically if there is a tail wind. Inside the car you get nothing. The only time I had a smell inside my car was when I had a valve cover breather. For some reason that breather let out fumes when I was idling and they would be sucked into the car by the AC. The outside air intake for the AC is right at the back of the hood and below the wipers.
Thread Starter
Cruising
Joined: Sep 2014
Posts: 14
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From: Fort Wayne Indiana
Thread Starter
Cruising
Joined: Sep 2014
Posts: 14
Likes: 0
From: Fort Wayne Indiana
I really appreciate all the advice guys, this is an awesome forum! Sounds like If I remove the valve cover breather and get a good tune, it will help with the smell enough for me. I don't want to put cats on or change the cam unless it's absolutely necessary. A few people have said it's too loud, but I love the way it sounds! In fact, I was going the opposite direction of a lambo the other day in town, and shifted at a higher rpm than normal, on purpose, and the guy driving the lambo turned to look at what was making the sound! I think I was smiling for a solid 2 days after that.
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a wideband o2 will tell you what the air/fuel ratio is while driving... you can see how rich/lean you are running under certain driving conditions