[Steve C.]

I suspect to make 660-670 hp @ flywheel with 250*ish intake and 650" valve lift using a hydraulic roller cam is going to be a stretch.

For interest evaulate Jim's 3950 lb race weight in relation to his ET an/or MPH get an idea of the horspower involved. His with 495 cid, 310cfm heads, Dominator carb on Victor intake. Note his hyd roller with 262/266 duration, 0.621 valve lift w/1.65 rockers.

On a old 462cid combo with 310+ cfm Edelbrock heads and a 254 degree Comp XE solid roller I made 600 hp at 6000 rpm with a Victor intake and HP950 carb. It should of been better but it had a lousy 9.7 compression ratio. My current 4.250" stroke 505cid with the same induction made 660 hp at 5900 rpm with only 10:1 compression, it currently has a 257 degree Ultradyne solid roller with about 0.689" net valve lift. If I were to make a change to a hydraulic roller for a similar power level I believe I'd have to add some additional duration.


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