While surfing another group (alt.trucks.Chevy) I came across a conversation about poor performance on a '82 S10. One issue came up about how the aftermarket dual exhaust might be flowing with not enough backpressure for the exhaust valves to operate correctly and causing the (or some of) the performance issues.
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By the way, one reader suggested to me in email that the aftermarket dual exhaust (already on the truck when I bought it) could be causing my performance problems. Apparently this V6 likes a certain amount of backpressure on the exhaust valves in order to operate well, and my dual exhaust (and lack of cats) could be providing too wide of a pathway, thus lower pressure. I think I may pursue this and try reverting to a factory exhaust system. Thank you, Rich!
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Do yourself a favor and ignore Riches advice. The less backpressure your engine has the better it will run. Bob
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What size are the pipes? Rich is partially right. That truck probably came stock with a 2 1/4 single pipe. Its not that it needs back pressure, but that it needs flow. A pipe that is too large will kill the flow-the velocity of the exhaust going through it.(its hard to explain) It might be worth while to research it a little.
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If we were talking about headers Rich could be right.... but we aren't talking about headers. If it has dual 6" pipes all the way back from the converter or even from the manifolds it isn't going to lose power because of it. Bob
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Oh, BTW, forgot to mention that I do not have catalytic converters. The truck would have come factory with one, but I've never seen it. Two 2" pipes all the way from the manifolds to the rear bumper.
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As I am considering new exhaust for my '88 S10 Blazer, I wanted to know what you guys thought.
TIA, Joe