5.7stroker

iTrader: (36)

Will the ARP Head Stud CA625 kit part number 234-4314 work with LS9 heads on a gen 4 iron block? I seem to recall there was something different about LS9 heads from other LS heads?

gnx7

iTrader: (28)

LS9 heads have 12mm head bolts. So you would have to have the drilled out to accept the larger CA625 units. I've used stock LS9 head gaskets and Katech/ARP head bolts (not studs) and made 1000-1200rwhp for years never losing a head gasket. Mainly 1/2 mile stuff turbo with LS9 block. Just don't get aggressive with timing. LS9 heads are superior because they are rotocast from a better grade aluminum and have additional webbing cast into the rocker arm boss area. They are 2lbs heavier than other production heads each.

I'm selling a set here if you need a set ported/redone by Katech.