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jluetjen jluetjen is offline
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Join Date: Oct 2001
Location: Westford, MA USA
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Camgrinder and Tony;
Given the smallish 34 mm ports I suspect that narrowing the lobe angle (and increasing overlap) will actually lose HP because of the intake restriction - inspite of the individual carbs. I've seen comments from Chevy engineers about the Le Mans spec Corvette motors (using the spec'd intake restricters) liking virtually no overlap. Basically, as the rev's climb the pressure in the intake starts to drop below ambiant proportinally with the increase in engine speed. With no overlap, as long as the pressure in the cylinder is less then in the intake when the intake is open, some charge is sucked into the cylinder. If there is overlap, and the exhaust ports have any pressure above the pressures of the intake and cylinder, the exhaust will push the charge back out of the cylinder and intake contaminating the charge.

Personally I think that the engine would respond to bigger intake ports (or 3.2 heads which would accomplish the the same thing) in combination with what camgrinder suggests and possibly larger carb venturi. But in the mean time I'd go out and enjoy the rush as the engine comes on-cam!
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John
'69 911E

"It's a poor craftsman who blames their tools" -- Unknown
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Old 12-09-2004, 04:04 AM
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