Any B18 or B16 would bolt right in. I guess you didn't get more replies because these motors are plentiful and cheap.

I have an affection for the B16 in its 160 HP guise, as I feel it is the epitome of what Honda was at the height of its development in the nineties, when Honda really just couldn't do anything wrong. It's not very torquey, though, so if you're talking about putting it in your ITR as a temporary motor, you mightn't be very happy w/it.

If you are after a Honda motor that'll push up against the 300 wheel HP barrier (normally aspirated), then you should have a look at the K motors. The K motors will not fit in your chassis using the same motor mounts, but they are not oversized dimensionally, and the motor mounts for the DC2 chassis are out there, now.

Did I understand what you were asking? Since you're in the ITR Forum I assumed that it was an ITR you were talking about.