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jluetjen jluetjen is offline
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Join Date: Oct 2001
Location: Westford, MA USA
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OK Wayne, that makes a little more sense. With the 98 mm cylinders for a 3.2 liter capacity and an S cam, I don't think that the 36 mm intake ports on your heads will be able to keep up with the cam's rev range. Keep in mind that the 2.7RS also used S cams and heads with 36 mm intake ports and it acted like a "mellowed" S. Your 3.2 is going to be taking 18% bigger gulps of air through the same sized ports. So at 5300 RPM your engine will be pulling the same amount of air through your intake ports as the 2.7 RS would at it's peak HP engine speed of 6300 RPM. I don't know how you will be able to move enough air through the 36 mm ports for your engine to ever reach the expected peak HP engine speed of 6300-6800 RPM.

If you want to replicate the 2.7 RS's power curve, you might want to take your intake ports out to 39 mm. If you want your engine's torque curve to look more like an early S's, then you'll want the intake ports out to 43 or 44 mm. You'll also want the exhaust out to about 39-40 mm.
'69 911E

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Old 05-15-2003, 02:36 PM
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