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Old 05-06-2016, 04:03 PM   #34
GRX
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Join Date: Jul 2010
Location: MD
Posts: 1,937
Vortec for sure. No disputing heads designed after the advent of flow bench technology. Typical double humps flow between 190 and 210 CFM on the intake side. True Vortec (not just center bolt cover type) are around 225 if I remember correctly. More critical than total peak CFM is port shape and flow time through the port. The valve spends little little time during the intake cycle at full open, so numbers at part lift are what makes real power. In other words, sacrificing low lift flow for high lift numbers can be counter productive. In this regard the Vortec are are superior as well.
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