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msgdsrf · 08-02-2013, 06:46 PM

I just went through all this on my new 383 which will be on the chasis dyno Tuesday (Woohoo!).

Typical cam specs for similar 383s will have about 280 adv/230 @ .050 and will then have lift about .45-.55.

If you want a good "hit", you want good torque. So I believe it's best to think in terms of air velocity instead volume of air at max RPMs. I'd rethink the carb size for certain and consider a well designed head with runners 180-190cc. You have some mismatching bits there with a 750cfm carb into 170cc head runners.

BTW, I'm at a calculated 11:1 running 91 pump gas w/ full timing and no predetonation. The rest of the numbers on Tuesday.

08-02-2013, 06:46 PM	#15
msgdsrf Registered User Join Date: Jul 2012 Location: White Salmon, WA Posts: 263	Re: 383 Build I just went through all this on my new 383 which will be on the chasis dyno Tuesday (Woohoo!). Typical cam specs for similar 383s will have about 280 adv/230 @ .050 and will then have lift about .45-.55. If you want a good "hit", you want good torque. So I believe it's best to think in terms of air velocity instead volume of air at max RPMs. I'd rethink the carb size for certain and consider a well designed head with runners 180-190cc. You have some mismatching bits there with a 750cfm carb into 170cc head runners. BTW, I'm at a calculated 11:1 running 91 pump gas w/ full timing and no predetonation. The rest of the numbers on Tuesday.