540 bbc build advice
#12
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So.....do you build a good breathing 496/502 that makes 550-600hp or do you strangle a 540 with dual plane intake, small carburetor, and small cam to make the same hp. An effecient 540 will make 600-650hp (or more obviously)
Effecient (high volumetric effeciency) motor or innefecient (low volumetric effeciency) ? Which do you want.....
#13
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Based on what? This is a completely wrong statement. "Marine" engines don't need any more "air" than any other engine. Cross sectional area in a 305 is way more than enough for a medium rpm 540 (<6500rpm) and the as cast heads I did with a simple chamber blend flow 385 cfm @ .700". Your average 540 with a 230@ .05 cam will need less than 340 cfm @ 5500rpm. Those same 305's flow that at .500" lift with NO portwork. Bump the cam to 245@ .05 and the rpm to 6000 and you're still needing <350 cfm. 315's flow more air, but IMO aren't "better", just a lot more expensive.
Last edited by Scott Foxwell; 10-14-2011 at 04:45 PM.
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Anybody have an idea to what this collaboration of parts might make and or with 320 afr or brodix heads instead of the 305 afr's?? closes ideas, speculations or even off the wall lol ?? The boat did 55mph with the 330hp 454 in with peanut butter heads in it, so now trying to hit 70 mph is my goal. Thanks
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Anybody have an idea to what this collaboration of parts might make and or with 320 afr or brodix heads instead of the 305 afr's?? closes ideas, speculations or even off the wall lol ?? The boat did 55mph with the 330hp 454 in with peanut butter heads in it, so now trying to hit 70 mph is my goal. Thanks