compression and cam spec thinking about
 

Was thinking about going with this on my stock 500 hps carb motors.

having port work done and shoot for 9.8.1 compression on stock heads.

cam specs was thinking 240I/[email protected] W/630/650 LIFT@115 CENTERLINE.

THIS WILL BE WITH STOCK GILL EXHAUST LONG WET RISERS.

WHAT IS YOUR THOUGHTS AS FAR AS IDLE, OCTAIN 89 OR 91.

Thanks for your input

You can't get the comp ratio to 9.8 with the stock heads and pistons unless there is some secret to shrinking the combustion chambers in the heads. Milling the heads .030 will put it at about 9.0-9.2 depending on the head gaskets used. Cam is too large IMO.

Talk to Dean Gellner or rmbuilder and have them put a package together that is proven to perform well.

Both Bob Madara (Rmbuilder) or Dean Gellner are good . Bob is grinding my new cams now. Bob # 585-654-8583 Dean #216-398-8500

Dome top pistons and chamber work on Vortec heads will get your compression up that high!

Thanks guys,

Your best bet would probably a 525EFI cam (crane 168741 ground on a 114 lob sep) or something close to it. Then have Gellner do the valve jobs and some mild port work on the heads.

SRP has a new line of small dome pistons that aim for a comp. ratio of about 10 to 1 for BBC. With 9.8 and iron heads, always use good premium 92+. When using stock iron heads, most cam grinders give the exhaust 10-12 degrees more duration than the intake because it flows so poorly. The big rectangular intake actually flows pretty good. The extra lift on the exhaust won't make it flow any better, just wear out the springs faster. Seems like an odd cam, who makes it?