Well at S/ST weight that 153 might net you mid 140's or so depending on how you have the stop set up. Definitely takes power in these classes to put up big MPH no doubt. We have a very good friend who we have helped with his B1 deal and S/ST set up who has been 8.70's all out and once in a blue moon if the air is great he can tickle 150 at 3000lbs. Roger has the advantage of being able to weight alot less. Not sure exactly what he weighs but the S/G minimum is 2200lbs so an honest 800HP would net home some decent MPH, but these days there are cars going over 180 with regularity in SG. If it were me I would be looking to get as close to that minimum as possible so no question an aluminum block would be used.