Thread: Blown 383 stroker cam selection

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At 10 lbs of boost with 8:1 static compression ratio, you're into race gas territory. Is that what you want?

The chart from Blower Drive Service shows that the most boost that can be used with 8:1 on pump gas is 8 lbs.
According to the calculator provided by Wallace Racing, using 8 lbs of boost and a cam with a 82* ABDC @ 0.004" tappet lift closing point would put the dynamic compression ratio at 8.6:1
Here is such a cam and the Wallace information. I used 20 ft. as your altitude.
http://www.cranecams.com/?show=brows...tType=camshaft
Your engine summary is as follows:
Bore - 4.03 inches
Stroke - 3.75 inches
Rod c-c length - 5.7 inches
With a static compression ratio of 8.0:1.
Your camshaft specifications call for an inlet valve closing of 82 degrees ABDC (after bottom dead center).
Your chamber volume is 111.98 cc's. With this camshaft your dynamic, or effective stroke is 2.45 inches.
Your dynamic compression ratio is 5.57 :1 corrected for cam timing, altitude, and rod length.
Your dynamic cranking pressure, corrected for cam timing, rod length and altitude is 98.28 PSI.
Your dynamic boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 8 PSI is 8.60 :1.
http://www.wallaceracing.com/dynamic-cr.php

Use a tight squish (piston crown to underside of cylinder head at TDC) of 0.035" to 0.040" to prevent detonation. Initial advance at idle should be set at 16-24 degrees with the total advance of approximately 32-36 degrees, all in by 2500-3000 RPM. It is very important to verify the advance curve.

Recommendations from BDS:
http://www.blowerdriveservice.com/recommend.php

ALWAYS CONSULT WITH THE TECH PERSON AT YOUR FAVORITE CAM GRINDER FOR A RECOMMENDATION OF CAMSHAFT, LIFTERS AND SPRINGS BEFORE LAYING DOWN YOUR LONG GREEN. DON'T TAKE THE WORD OF AN OLD WORN-OUT GEARHEAD LIKE ME.