Rod length and stroke?

This is not a sex question!!!!!!...... Just curious if any of you 409 specialist have tried a 3.76" stroke with a 6. 535" rod? Or should I stay with the 4" stroke and 6.385" rod?
 
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Don Jacks

Well Seasoned Member
Supporting Member 3
If you're looking for quicker higher rpm,then go with the shorter stroke.Using the 6.385 rod will allow a lighter piston which helps.As to peak hp,not that much but it will require more rpm to get there.The same with torque,you're going to lose some and what you do have will peak higher.Generally the engines peaks will be moved up by 500 rpm per .250 inch reduction in stroke all else remaining the same.A gear change may be inorder.This is like the old big block 427 vs 454 debates.
 

1964SuperStocker

Well Known Member
Supporting Member 3
If you're looking for quicker higher rpm,then go with the shorter stroke.Using the 6.385 rod will allow a lighter piston which helps.As to peak hp,not that much but it will require more rpm to get there.The same with torque,you're going to lose some and what you do have will peak higher.Generally the engines peaks will be moved up by 500 rpm per .250 inch reduction in stroke all else remaining the same.A gear change may be inorder.This is like the old big block 427 vs 454 debates.
But if you can make the same power at a lower RPM then it would be recommended by all that you do so. RPM's costs money and costs more in wear and tear as well. To each their own but there is no replacement for displacement.
 
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