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Old 10-15-2012, 02:57 PM
ap72 ap72 is offline
How fast is fast enough?
 
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Quote:
Originally Posted by techinspector1 View Post
Here's a checklist that I wrote and that has been improved by other members. The intake closing point of the cam must be matched to the static compression ratio as you will learn by reading the tutorial from Crane that's shown here.....
http://www.crankshaftcoalition.com/w..._compatibility
I wouldn't worry about this link too much as it doesn't account for displacement, heads, intake, exhaust, application, carb, fuel, etc. Without considering those aspects its as useful as any advertisement or summit catalog (not much), I still can't figure out why it hasn't been deleted as its VERY misguiding.

Truth be told with E85 as your fuel you can run as small of a cam as you want, and your heads will go into choke right under 6,000rpm or so so there's no sense in camming for more than that unless you want your efficiency to go to hell. Assuming a good dual plane intake, headers, and exhaust, you'll want about 220-225 duration on the intake, and 225-230 duration on the exhaust for a hydraulic cam @.050".

As Cobalt mentioned stock heads peak out at a hair over .500" lift, going past that on stock ports and valve job won't gain you much (though it will pick up a little).

For a good street 350 stick with 1.94/1.5 valves but get a good valve job, open the throat to about 89-90% and open your runners up (finished volume around 190cc's with good even runner taper is a good target for Vortec heads). Those mods can pick up another 25+hp on a well built 350.
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