Cutout downpipe benchmarks
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Joined: Jun 2003
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From: Orlando, FL
Cutout downpipe benchmarks
I have Quicktime Performance's electronic downpipe on my car, so I did a test with it opened and closed. I have an 03' with K&N air filter, downpipe, flash and boost set to 21psi in the open cutout mode. Closed, boost drops to 19psi and runs richer by about .3 AFR wideband (10.9 vs 11.2 on avg). Here are the power results (I took the average run on both open and closed to keep data from being skewed from those hero runs). This confirms the idea that no back pressure is better, because in open cutout mode, the car spools up about 150rpm's faster.
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From: Virginia Beach, Virginia
an interesting test would be to pit it agains something like the best BR exhaust on a dyno. I'm sure the higher the HP engine the more substantial the gains would be in favor of the cut out.
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This might be a good set-up for the Cali guys.
You could have a O2 housing, 3" downpipe, cutout, then the stock exhaust so the po-po's have nothing to beeotch about.
But, then again, I am sure they will find some other reason to write you a ticket too.
You could have a O2 housing, 3" downpipe, cutout, then the stock exhaust so the po-po's have nothing to beeotch about.
But, then again, I am sure they will find some other reason to write you a ticket too.
ur seeing such a variation because of the stock cat thats in place....
Put a testpipe in and the hp difference won't vary as much and the boost will stay the same....
The stock catback on a stock turbo car is good for 10whp max. I trap less than 1 mph more with my cutout open versus closed. i run a megan downpipe and ultimate racing testpipe.
If you notice the main difference is the 500rpm faster spool with the cotout open. Thats the main reason i run it.
Cheers!
Put a testpipe in and the hp difference won't vary as much and the boost will stay the same....
The stock catback on a stock turbo car is good for 10whp max. I trap less than 1 mph more with my cutout open versus closed. i run a megan downpipe and ultimate racing testpipe.
If you notice the main difference is the 500rpm faster spool with the cotout open. Thats the main reason i run it.
Cheers!
ur seeing such a variation because of the stock cat thats in place....
Put a testpipe in and the hp difference won't vary as much and the boost will stay the same....
The stock catback on a stock turbo car is good for 10whp max. I trap less than 1 mph more with my cutout open versus closed. i run a megan downpipe and ultimate racing testpipe.
If you notice the main difference is the 500rpm faster spool with the cotout open. Thats the main reason i run it.
Cheers!
Put a testpipe in and the hp difference won't vary as much and the boost will stay the same....
The stock catback on a stock turbo car is good for 10whp max. I trap less than 1 mph more with my cutout open versus closed. i run a megan downpipe and ultimate racing testpipe.
If you notice the main difference is the 500rpm faster spool with the cotout open. Thats the main reason i run it.
Cheers!