I wouldn't do anything over an 84mm in an s400 frame. The gain just isn't there, and I doubt power would go up much. I bet Craig could spool an s475/95mm, or he would find a way.
Yeah, but the power still isn't going to go up much, if any. Plus he already has an s475, why buy 2 more and not get much more power? I like the s366/s483 set up, I just don't think its what Craig is after.
Craig never seemed to have a problem with the drivability? I think he enjoys the way it drives, and he said with the addtion of their manifolds, and another pump it spools even better.