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Discussion Starter #1
Ok, after my last dyno session, with just the SRT and Greddy, I achieved 203 RWHP/203 RWTQ, SAE.

After adding the XERD pipe, I went back and dynod again- 206 RWHP/208 RWTQ. SAE.

HOWEVER, that was at peak. From 3000rpm to 4500rpm, the new curve was significantly higher, on average about 8hp/8tq, and again from 5800 to redline, the new curve was significantly higher, about 8hp/8tq. This seemed to agree with what I had been "feeling," which was a boost in midrange power, although the dyno also indicates an additional boost in top-end power. At no point in the curve, tested from 1500rpm to redline in 4th gear, did I lose hp or torque, while the area under the new curve was dramatically improved, due to the additional midrange power.

While peak(highest) hp and torque were not dramatically improved, the gains were quite evident on the dyno. One of these days, I'll get off of my lazy ass and get around to scanning and posting.

A/F graph looked really good, too- pretty much flat like this:

14 ....................................
13 ................./++++++++
12 +++++++/...................
11 ....................................
....0..2500...4500...5500...red

-C
 

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Yeah, good point. Although minimal top hp gain, the mid-range increase throughout the curve is what's useful. Now time for some boost :wink: .
 

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Do you think you would have gained more hp with a rear section exhaust instead of a full cat back? Im just guessing based on edgy's experiance with the xerd pipe and then losing hp when adding the dtm b pipe wich makes a rear section exhaust a full catback.
 

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Discussion Starter #5
honestly, I cannot speculate on that. I really have no idea whether or not I would have gained or lost hp with just a rear section- With a 3.0L 6 cylinder engine, I am assuming that the catback (which still maintains only a 2.5" or 2.66" piping diameter) would still lend itself towards gains in the top end, perhaps at the expense of some low-end torque? The peak #s should still be higher, in my experience.... not that that is necessarily a good thing- HP is no good if it's not useable in a practical sense. :wink:

-C

what's funny is that I said I cannot speculate, then in re-reading my post, I did just that. oh well.
 
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