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Discussion Starter #1
I got a chance to buy a nice set of 049 heads from a friend with alot of money stuck into them. I'm not the type of guy looking for every possible hp but I'm a little worried about the cr being too low. I have a .070 short block with flat top pistons -3cc. and a 4.25 stroke. It has a 11-770-1 comp solid roller cam installed.
I did the KB compression calculator and came up with 8.9 using a thin steel shim. Will these perform as well as a set of closed heads with a much higher compression?. I like the idea of using 87 gas.
I need to know kinda quick,
Thanks
 

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Those are normally a 122cc chambers and you will probably end up around 8.5 if your lucky. Not a good combo for power but you do have plenty of cubes. I am sure there will be more people to chime in.
 

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I'm coming up at around 8.6 with pistons .005 in the hole and a .035 gasket, 119cc chambers. With heads milled to 110cc chambers, it bumps to just over 9:1.
I use the calculator on the Ross pistons site, I've found it to be easy to work with and about as accurate as any.
 

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Discussion Starter #4
Thanks Guys,
It sounds like If I mill them down they should be fine for my application. The builder that did the work on these heads is a top notch guy in my opinion and has done several motors for me. I guess I'll get them and check the cc's and go from there. I figured their must be someone out there that has this combo or has seen it before.
Thanks again.
 
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