From personal experience building NA motors with the older, less supported blocks. Over 1000 hp they started falling off for no reason. The first one I used made just under 1200 on the 3rd pull. Next few pulls power went down, and down. Thought something was hurt, but could find no evidence. Ripped it apart, re honed it, and power came up, then fell again. Finally attributed it to unsupported cylinder walls. Eventually settled in at a lower number and stayed close to it. Same experience with 3 different motors.


I have seen guys with blown motors making 1500+ with them. I don't think they're going to fly apart or anything like that. Just not as strong where it counts for power.

I have heard, but not personally seen, the later blocks that supposedly are better supported in the walls. Reality in my mind is there is only so much that can get around the rings, so if you need more power, just turn the blower harder.

The KB's are for sure the best cast option out there for strength, but you need the patience of a saint to get one. Should Noonan get an available billet water block out there, game over for every other racing mopar block maker.