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Exhaust leaks = Power loss...

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Old 11-19-2011 | 05:36 AM
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Default Exhaust leaks = Power loss...

Just thinking about it, a "Small" exhaust leak (5-7mm wide) on the Xover to exhaust manifold flange.

How much of a power loss and spool loss will this cause?

Searching doesn't tell me anything.
Old 11-19-2011 | 07:53 AM
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A rule of thumb I heard years ago, was that a hole in the exhaust the diameter of a standard pencil could result in a loss of gas mileage of up to 10%. Power loss would be difficult to calculate. A chassis dyno could see the difference, but not likely your butt dyno.
Old 11-20-2011 | 02:12 PM
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Originally Posted by Paulyy
Just thinking about it, a "Small" exhaust leak (5-7mm wide) on the Xover to exhaust manifold flange.

How much of a power loss and spool loss will this cause?

Searching doesn't tell me anything.
WELL............

Somehow my cross over pipe broke in half right under the turbocharger.... My 2.8L couldn't spool the little K26.
Old 11-20-2011 | 04:06 PM
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It will sound like ****, rape your gas mileage, and probably take at least a solid 30whp.. at least in my case. Exhaust leaks are a never ending battle with a 951
Old 11-21-2011 | 01:36 AM
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Originally Posted by piperporsche180944
WELL............

Somehow my cross over pipe broke in half right under the turbocharger.... My 2.8L couldn't spool the little K26.
LMAO, you've got a different problem there!

Originally Posted by MM951
It will sound like ****, rape your gas mileage, and probably take at least a solid 30whp.. at least in my case. Exhaust leaks are a never ending battle with a 951
i've got a small one on the x-over to headers flange, i wont seal i can't hear it on idle, only on boost so i can say it's robbing spool time!



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