Thread: maybe a 4-71 blower

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I have a chance to buy a new 4-71 blower at about 1/2 the price of it new. My understanding of a blower since I've never had one is using my cam which has a Dur. .050 218-224, the lobe seperation is good for my cam for lower rpm usuage(say from 2,000-3,000)rpm running no more than 3-4 lbs. of boost. Now understanding that I would be better getting a cam that would have more duration and lobe seperation to start to take full advantage of the blowers potential power building ability. My understanding is the more duration rather the lift, the better. Right?

If I wanted more performance after I have fixed duration situation, then I can go for a higher lobes. This way I can take the correct advantage of the blower use rather than wasting all the power making boost at the exhaust. Am I right?

All you who have run blowers before, what cam do you think I should go to? Rember I'm running a sbc 305 bored to 315 with flat top pistons and compression of 9:2 which is why I can't run tomuch boost.

With that engine setup, a 4-71 is overkill. Either decrease your C.R. with some different heads, or put the blower on the bench until your next engine is ready to build.

Just put some 350 heads on your 305 and that will drop your compression. I thought supercharged engines like short duration cams with big lift. With a long duration, it just blows the fuel/air right out the exhaust during valve overlap.