69 camaro running in the 10s

[markjohnson]

I've owned & fooled around with these big engines quite a bit and I've built 540 CID's based on GM Gen 6 502 blocks and you can get a 4.25 stroke crankshaft for less than $800. A 4.500 Stroke crank starts to get pretty expensive. Plus, I've NEVER seen or heard of anybody making a 572 from a short deck block such as the 502 CID. I'm sure it can be done with terribly short connecting rods in that short deck height block but it's really just not a good idea. Even on GM's very own 572 Crate motor, they avoided that 4.500 stroke crank shaft and chose to only go with a 4.375 stroke in a Tall deck block. 540 CID short deck engines have become immensely popular and represent the best bang for the buck.

[VintageMusclecar]

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-edit-

No need to further derail the OP's topic...

[70 ls6 convert]

Thank you so much,Thats what route im goin 4.25 crank,When i order the rotating assembly,do i want to just order a new fly wheel and balencer and get the whole setup ballenced,and then on the cam side im racing a 4sp m22 and 373,whats the best cam set up and valve spring for my engine thanks again kris...

[markjohnson]

Something nice about the newer Eagle 540 Recip. assemblies is that they come Internally balanced compared to the older Externally balanced ones. You can also have the choice of .250 or .400 longer rods but with the short deck of your block, I think I'd go with the .250 longer rods just to try to keep the wrist pin out of the lower ring lands. As far as camshafts go, pick your favorite camshaft company with a solid Roller with around 250-260 @.050 lift, .650-.670 lift and 110 degree lobe centers. Use the recommended valve springs of whatever camshaft you choose. Now, you're really pushing the outer limits of your particular cylinder head casting and while there would be power to gain from a larger head, I think you could still get away with using the heads that you have. With the stock location exhaust ports on your heads, just make sure you used a dual-pattern camshaft instead of a single pattern and that it has about 8-10 degrees more duration on the exhaust lobe. I don't know what you're going to use for an intake manifold or what kind of hood clearance you have but I'm a big fan of Dart intakes and 950-1000 4150 Double Pumpers. While we seem to have drifted off topic a bit here, I hope this information is helpful and if I can be of any more assistance, just PM me. Thanks.