1990 C4 Exhaust
Thread Starter
Le Mans Master
Joined: Jan 2008
Posts: 7,030
Likes: 10
From: Edmonton, Alberta
1990 C4 Exhaust
Hi everyone, This may seem a strange question, but when checking the exhaust at the rear of my car only the two outer tips on each side were working and nothing coming from the inners tips.Are these just fake or do I have a problem. It is a totally stock exhaust actually the original from 1990
Safety Car
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From: Mt Laurel NJ
St. Jude Donor '06-'07
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
Le Mans Master
Joined: Apr 2000
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From: DrunkDefender
CI 1-2-3-4-5-6-7-8 Veteran
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St. Jude Donor '07-'10
My 90 had both sides working(all4) as delivered from GM, go figure. I know that there was a reason for it too, be it an RPO code or something. I just cant remember what it is.
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From: This city NEVER sleeps! Frank's back yard!
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Le Mans Master
Joined: Sep 2003
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From: eastern NC
I have an '85 Corvette with Z-51 that I ordered new in September of 1984. I came with only the outside pipe flowing exhaust. Absolutely nothing on the inside tip including a "small" hole for moisture. I tried a couple of times to punch a hole through the casing to at least equalize the color of the tips, as the outside tip was always darker than the inside tip. Because of the angle between the tip and the muffler, and the toughness of the original muffler I could not punch a hole through it.
I took it to a friends muffler shop and he used an arc welder to reach in carefully and "burn" a hole into the muffler casing where the dummy tip is welded on. Now all four tips flow equally. (It took 15 minutes and cost me $20!) There was a slight increase in resonance from the modification, but it's not at all objectionable and it also sounds a lot healthier.
Two friends in the past year both purchased '91 Corvettes with the stock exhaust on them and both took them to the same shop and had him open the center of the dummy tip. Both were very pleased with the results.
Good luck... GUSTO
I took it to a friends muffler shop and he used an arc welder to reach in carefully and "burn" a hole into the muffler casing where the dummy tip is welded on. Now all four tips flow equally. (It took 15 minutes and cost me $20!) There was a slight increase in resonance from the modification, but it's not at all objectionable and it also sounds a lot healthier.
Two friends in the past year both purchased '91 Corvettes with the stock exhaust on them and both took them to the same shop and had him open the center of the dummy tip. Both were very pleased with the results.
Good luck... GUSTO