Jesse Lackman made 520hp/548 tq IIRC on a 408 with some far from maxed out RHS 360HPST heads and a mildish (238@.050) hydraulic roller. the 360HPST heads were the starting point for these heads.

here's a link to Jesse's engine thread

dang it, looks like Jesse beat me (:

about the only things these have in common with OEM "X" heads are the name and the fact they're iron......

Last edited by patrick; 03/03/09 01:40 PM.
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