Any experience low hp due to dented in dp?

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Sep 16, 2011 | 02:36 PM

SPRAYED 01

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Any experience low hp due to dented in dp?

My 3.5dp had to be beatened down alittle to fit the sway bar. Its not to bad but im having low hp issues on the dyno.

Comp 80/79 billet wheel,1.32ar 3.5 dp for about 3 feet then 3 inch then cutout.

With a forged 370ci 232/236 cam through a locked converter and 9 inch at 7lbs its only at 490whp and 545ftlbs. The main issue is that it peaks at 5100rpm.

Tuner thinks its may be a restriction in the turbo system.

Sep 16, 2011 | 02:39 PM

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At 11lbs it did 590whp but again around 5100rpm peak.

Sep 16, 2011 | 05:26 PM

Nitroused383

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Post up the dyno sheet, was the cam properly degree'd in?

Sep 16, 2011 | 05:38 PM

98Z28CobraKiller

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undo the Dp and see what happens.

Sep 16, 2011 | 06:15 PM

Boo"SS"t

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I can't see how it could be choking it that bad, unless you're loosing 1/3 or more of the flowpath from that dent. Is your exhaust all the way to the back and thru a muffler or just dump at the bottom?

Sep 16, 2011 | 06:42 PM

Sweet_SS

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I seriously don't think that your DP is an issue. We tested the back pressure on my stock LS1 with a 3 " downpipe (no cut-out) on the TC78 with .96 a/r. on 8 psi and I flow all the way past 6000 rpm. Could be your muffler...it you have one