Don't see any reason why can't put big block std offset rockers on the INDYBrocks. I'm 100% positive my PRW Stainless bushed Big Block rockers would work on an INDYbrock on the ICH SB shafts.

Road Race car I'd think the iron head weight would be big disadvantage.

Power wise I don't see big difference between a fully ported INDYBrock or a set of W2's. W2 has little more potential depending on version. I know which one is easily repairable & which one is'nt..... also know which one is crack prone & which one is'nt.....