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Losing power from catless exhaust....
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08-10-2008, 06:35 PM | #1 |
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Losing power from catless exhaust....
Is it possible to lose power from a DP back catless exhaust? I put an exhaust system on this weekend and I honestly think I have lost power. It feels slower in the low end and doesn't launch nearly as hard as it used too.
What do you guys think, is this just in my head or is my butt dyno correct?
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08-10-2008, 06:55 PM | #2 |
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If properly designed, no. The best exhaust for a turbo system is no exhaust at all behind the turbine. However, sound increase does not always equal flow increase. Lastly, sound increase may be drawing attention away from the feel; i.e. a placebo affect.
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08-10-2008, 06:57 PM | #3 |
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Did u make sure you capped the vacuum hose from the OEM exhaust flap tightly....I heard someone on this forum also had this problem and it was the vacuum hose not completely sealed
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08-10-2008, 07:03 PM | #4 | ||
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What could make it be not properly designed? Quote:
I will clamp it up tightly in the morning tomorrow.
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08-10-2008, 07:14 PM | #5 | |
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08-10-2008, 07:18 PM | #6 | |
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Let me tell you a quick story of a GN racer who was on the cutting edge at the time. He made some changes to his car and on his first pass was sure he was slower. But when he picked up his slip he was shocked to see he went 3 tenths quicker and set a new personal best. What changed was the shape of the curve which didn't feel as quick but actually was. Not saying this is the case but is something to consider. |
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08-10-2008, 07:21 PM | #7 | |
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Maybe I will just go dyno again and see what has changed..... Thanks guys
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08-10-2008, 09:17 PM | #8 |
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i bought a g-timer off of amazon for $45. now i know what acceleration g's my car pulls in each gear at the various rpms. its pretty consistent in similar wheather. if i changed an intake or an exhaust, i would be able to tell very easily how my car's pulling - not depndent on launch or technique. for a guy who changes his mods all the time, i'd think this would be a great investment.
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08-10-2008, 09:19 PM | #9 | |
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I think I am just going to go and get another dyno done soon to see if there was a loss in power.
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08-10-2008, 10:35 PM | #10 |
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I dont know if its the same with turbo cars as much as NA... but on big HP NA cars putting a full out exhaust dropped some low end torque (not a ton but some). It made up for it in the higher end. Dyno and see if there is any difference... also check with terry there may be an A/F issue that could be causing it. Hmm another thought could be the spool up time - its a faster spool with no exhaust so it may have a little less "jolt" ie may be smoother. Not step on it wait a sec and it hits... it spools and makes power smoother. Just a couple ideas. Hope it works out kyle!
Mat
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08-11-2008, 07:13 AM | #11 | |
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Thanks guys...
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08-11-2008, 07:47 AM | #12 |
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It is different, the turbine acts as the back pressure for the engine. No exhaust is the best one for a turbo set up.
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