Don't get me wrong, I like the rb motors but the price of the parts to replace items on the rb is about three times as expensive as an sr. As for the KA-t, there are people around who have put down good numbers and even some ghost tales of some around georgia which noone has ever seen but all the KA-t guys have "heard" of. Yes to put down 500whp get ready to put down some loot. I just got thru building 3 sleeved, race ready sr bottom ends and 2 built heads for this season. If tuned correctly you can get 375-400 with a fully stock motor and everything bolton upgraded, but if you have any lean issues occur it won't take long for the motor to go. Why not a 2jzgte???????????????????? Supra MKIV turbo motor, just a thought....