I have a '65 Chevelle with a two-bolt main small block, Edelbrock aluminum heads with the big valves and 64cc chambers, 1.6" roller tip rockers, and forged flat top pistons. I'm thinking strongly about a blower, but I'm told that 9.1:1 compression may be too much compression. Is it possible to under-drive the blower to make up for the compression, and how much boost is right for this compression. Is there a formula that I can use for this and for what size pulley gets how much boost? I'm a newby at this and don't want to break anything (at least until race day).

Thanks,

Jon

I'm thinking strongly about a blower, but I'm told that 9.1:1 compression may be too much compression. Is it possible to under-drive the blower to make up for the compression, and how much boost is right for this compression. Is there a formula that I can use for this and for what size pulley gets how much boost? I'm a newby at this and don't want to break anything (at least until race day).

Thanks,

Jon

For a Weiand Low Profile blower, 9.1:1 shouldn't be too much...

Not ideal, but not too much...

Not sure what Weiand offers for extra pulleys, etc to adjust the boost levels...

I have seen charts before indicating boost levels and how they relate to compression, but I can't recall where they were...

My friend ran a B&M mini-blower for years (at least 8 years) on a 9.0:1 crate motor (345HP Ford 302 with aluminum heads)... B&M was bought by Holley, which also bought Weiand, and his old B&M looks IDENTICAL to the current Weiand part, except the deleation of "B&M" markings (even has the same "Forced Induction" cast into the snout)...

9 to 1 is about as high as you can go. Somewhere in the 8's would be better I am told. I am thinking of doing the same when winter arrives. I have decided against the weiand 177 for the polished D-1SC Procharger. I will be changing my pistons to lower my compression. I opted for the Procharger because I believe it offers much more horsepower and is user friendly. But if I do it right and replace my cam and a bunch of other stuff it will cost around $5,000.00 but to have between 600 to 800 horse on 93 pump gas without having to run an intercooler is going to be fun. God I feel sorry for my rear tires.

Here are instructions for the blower. If you scroll down it has a chart showing boost for different compressions. http://www.holley.com/data/Products/Technical/199R10244-1.pdf

Bdub