good luck with your problem
Exhaust Fume Problem
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Intermediate
Joined: Nov 2008
Posts: 48
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From: Houston Texas
Exhaust Fume Problem
I have a 1998 C5 Coupe and I have a significant problem with exhaust fumes coming into the passenger compartment when the windows are down or the top is off. Does anyone else have this problem?? Is it possible to resolve this by extending the exhaust tips further out? Perhaps the airflow of the car is pulling the fumes forward? I really wish I could resolve this! Thanks for your suggestions.
Bobby
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Don't recall ever having that problem in mine - the tips should be far enough back to allow the exhaust fumes to flow away from the car. Even though you have checked for leaks, you might want to take it to a muffler shop and have them check it over. IMO, extending the tips out will not look all that good.
Racer
Joined: Sep 2007
Posts: 369
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From: Calgary AB
IMO, with the cats gutted you are smelling the raw exhaust which really does stink. When stopped, you will smell the exhaust with the top or windows down, no doubt about it. In other words, the gutted cats are magnifying what happens all the time. The opinion is based on the fact that you're confident you don't have a leak. Good luck my friend.
Matt
Matt
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From: Houston Texas
Well I guess I now have a "higher opinion" of cats! 
This sucks. I wonder if someone has a wind-tunnel video of a C5 so I can see the airflow and see if extending the tips a bit would make a difference. I hate to hack the exhaust up unless I know it will make a difference...
This sucks. I wonder if someone has a wind-tunnel video of a C5 so I can see the airflow and see if extending the tips a bit would make a difference. I hate to hack the exhaust up unless I know it will make a difference...
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Well I guess I now have a "higher opinion" of cats!
This sucks. I wonder if someone has a wind-tunnel video of a C5 so I can see the airflow and see if extending the tips a bit would make a difference. I hate to hack the exhaust up unless I know it will make a difference...
This sucks. I wonder if someone has a wind-tunnel video of a C5 so I can see the airflow and see if extending the tips a bit would make a difference. I hate to hack the exhaust up unless I know it will make a difference...
IMO, even if you extended the tips out a foot, I doubt it would make any difference in getting the exhaust gasses out of the slipstream. If its not a leak, you need to put cats back on and lose the huge 5hp you gained by gutting them. Probably not what you wanted to hear.
