What all is involved in upgrading Gen5 heads to Crane Gold Roller Rockers? Are ther any clearence issues with the stck merc. valve covers? Should springs be replaced at the same time? Thanks.

You need to grind the oil drips off on the valve covers. You also need to grind one corner of one of the rockers.

I'd change thw springs if there over 200 hrs old...my .02

also depending on how you are doing this....if the exhaust is on the engine then you may have to loosen the exhaust from the block to get at the inside valve cover bolts. Unless you happen to have a realy skinny u-joint socket assembly. The SnapOn one barly worked for me last time out.

If it is gen5 It has non-adjustable valvetrain. To run roller rockers, you need adjustable valvetrain, Crane makes a kit for this (#99152-16), its just a set of rockers studs that have 3/8" bottom thread a 7/16" upper thread so you can run roller rockers. Then you need valve covers. We ordered a set of Eddie marine valve covers, they are nice pieces, tall and angled on one side to clear the exhuast.


Travis

Why? Do you plan on spinning high RPM's? If not, I've heard there is nothing to be gained (except more valvetrain noise).

I have to pull the heads due to a bad intake on #1 so while I've got them off I'll do some upgrading as I plan on doing a Whipple soon and Dustin suggested it would be a good idea to do the Crane Gold Rockers

Since you have the heads off already, I would upgrade to full 7/16" studs. I don't see the advantage of getting 7/16" studs, while having 3/8" screwed into the heads. Get the heads drilled and tapped at the machine shop before re-assembly..