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Re: Why a Custom Cam
Quote:
Originally Posted by MonsterMach
It will have a custom cam and the focus of that cam will be to get the optimum Dynamic Compressioin Ratio while still maintaining the ability to pass emmissions testing.
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Dynamic compression ratio, especially as derived by many of the on-line calculators, is an almost useless spec. They take into account only when the intake valve closes, not when it opens and starts admitting mixture or how efficient the intake side of the engine is. The volume of compressed mixture determines how much pressure will build in a cylinder after the intake valve closes. What you need to know is dynamic cylinder pressure of the running engine. And it changes according to rpm, less time for cylinder filling at higher rpms.
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70 Maverick Grabber, 5.0 (Performer RPM 2.02/1.6 heads, RPM intake, Comp XE266HR roller cam, Holley 650 DP, long headers), "Z" T5 w/Steeda TriAx shifter, 9" "N" case Trac Loc w/3.89:1, 31 spline axles.
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