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Old 12-09-2006, 05:45 PM
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jm455ho jm455ho is offline
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Join Date: Jan 2005
Location: Montreal
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Quote:
Originally Posted by formulabird428
the Kauffman's suggested a 1 3/4 header, because it works on their heads quite well. However, I had them test a set of 2" primaries, and the dyno results are IDENTICAL. I'm talking, within 2 hp all across. Same thing with torque, about +/- 5hp across all rpm's. Max hp/torque occurred at same values too...

does that sound strange?
We tried 1 3/4 and 1 7/8 headers on our 455 with KRE290 heads and found a significant increase in the midrange with the bigger headers. Up to 31 lbft torque increase at 4600 rpm. #41 is 1 3/4 header and #56 is 1 7/8 header in the attached graph.
Attached Files
File Type: pdf 41 vs 56 graph.PDF (18.1 KB, 41 views)

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