max stroke in a gen 4 bowtie
12-31-2002, 09:58 AM
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The truth is, the book says 4.6 but when you get into that kind of stroke you get into maximum piston pin height, which is ok. The problem comes when you have to use a really short rod. Your piston speed increases which promotes increased ware and will also lower your rpm limits.
In my opinion I wouldn't put anything bigger than a 4.37 stroke in a 9.8 block.
my .02
DAVE
In my opinion I wouldn't put anything bigger than a 4.37 stroke in a 9.8 block.
my .02
DAVE
12-31-2002, 10:59 AM
#4
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I know that you can go to 4.5", but there are rod angle problems and cam clearance issues. Not to mention a ton of machining that would be required to the pan rail. By the time you are done, you'd be better off going with a merlin II block. Now if practicality is an issue, then it's 4.25".
01-01-2003, 02:49 PM
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I agree with Bobby, you can do a lot of things that are not really practical. 4.25 with a 6.385" rod still leaves room for rings and gives more power in the 5,000 and up rpm range. The bigger the bore, the more you unshroud the valves and the bigger surface for the cylinder pressure to act on(MORE POWER). A 4.25" stroke and 4.31" bore is a 496, a great engine if you have a Chevy block!
01-02-2003, 08:25 AM
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Hello MTM,
The 4.25" stroke will give you almost as much torque and 6.385" rods are a common set up. The bigger the bore, the better they run-even better than the displacement increase would indicate because of better air flow. Depending on your block, we like to bore 4.560-4.600", leaving one more boring to 4.625" if ever needed.
The 4.25" stroke will give you almost as much torque and 6.385" rods are a common set up. The bigger the bore, the better they run-even better than the displacement increase would indicate because of better air flow. Depending on your block, we like to bore 4.560-4.600", leaving one more boring to 4.625" if ever needed.
