RB maximun valve lift?

[HOLESHOT]

Need to know how much valve lift these motors will allow.Specs are .050 deck,heads cut .016 ccd 88,.020 head gaskets with TRW flat top pistons without valve reliefs.Currently run stock rockers with .509 but thinking of going to a roller.Possibly I may only go 1.6 roller rockers if there is room with the 509.Ideas?

[MoparBilly G]

I always stopped at the .509 with no valve reliefs, had people say they got away with the MP 296,557 solid on that setup, but a .509 with 1.6 rockers would have more lift than the .557 solid, so I think that would be pushing it.

[WS23]

Holeshot, when your are playing it close the only way to be sure is to measure it. I'm sure you know that already. Just because it measures ok in our engine doesn't mean yours will be ok.

Having said that, the last 440 we built measured .045 in the hole with flat top pistons. Using Felpro head gasket .039 crush & a .474 lift MP cam, it measured .228 minimum clearance on intake and .287 minimum clearance on exhaust using stock head with 86cc chambers. Cam was installed straight up. Plenty of room.

OK you can use these numbers as a guideline & do the math in reverse, but you know it's no guarantee. If you take my minimum clearance minus the difference in head gasket, minus the difference in the head shaving, plus the difference the piston in the hole, you'll get a ball park idea.

I've done this many times but I still ALWAYS measure, just to be sure.