Stroker motor combonations

Brian at IMM Engines just told me he is building a 408 Stroker based off a 360 Stock block, using Indy's TA head which is the old IndyBrock head...with his own porting, TD rockers and a super victor intake. Pretty sure it will have a big solid roller. He said they have upgrades like 5/16 valve stems and they use BB Mopar rockers with a 1.7 ratio. He says there is less drag on the valve with the longer rocker. He was saying 600+ HP, so there you go!