rebuilding 440

[hotrodbelair]

i got a 440 with 10:1 compression stock head. im goin to bump up the compression to 12:1 stage 2 hotcam port and polish and 3 anlge valve job. do u think this engine can handle the compression with stock head studs and rod. i heard from someone even if your just doin a drop in cam u should upgrade the valve train too.

[enduro400rider]

not only will the head studs pull out at the compression, but the crank will be in danger of breaking also. it happened to a memeber on this site he had pics of it, the crank broke and smashed through the cases. i wouldnt go over 11.5:1 but even at that comp you should get some HD studs

[440exnacsracer]

stronger valve springs are never a bad idea for any modified motor, but if your on a budget, you should be ok with the hotcam. a cam will also reduce the risk of blowing headgaskets as the increased duration decreases the stress on the headgasket. with 12.5:1 compression, though, i would definately reccomend HD studs, or youll be getting really good at replacing head gaskets. as for the bottom end, i ran around 13:1 compression on a ex for many hours, and the bottom end is still in perfect working order.