How fast have you gone with exhaust manifolds?

AndyF on moparts had several magazine articles on his B/RB engines... I know he cleared the 500hp mark with at least one of the stroker combos. You should cam it for the loss of scavenging and to eliminate some overlap. The FAST guys use that along with the extrude and hand porting to get the power numbers. Nothing about those cars is as it seems. The LA hp manifolds are pretty good. The HP big block ones are not too shabby. The rest can be tossed to the scrap guy.