Study,

I've spent a lot of time looking over the engine issue myself and if you spend any time at the Ofna boards, you will see that one of the engines that alot of the H7 guys turn to is the OS21RG. I was kind of perplexed why somebody running an 8 port (rated at 2.5 hp) would swap it out for a 21RG (1.9 hp). It never really made any sense to me until I ran against a stock RG in an H7 at my track. That dude KILLED me! The torque was amazing! When he blipped the throttle, it was gone. You know as well as I do that the 8 port is no slouch and that it would probably make up some of the difference on the top end, but the RG is a real performer.

Outside of the engines performance, the price is out of this world! You can get it with a pullstart for 139.00 or without a pullstart for 109.00 at Tower. I have the Race ported 21RG in my PBS and when I hit the throttle, the tires just light up! It's absolutely sick! This engine makes a lot of power down low. When comparing dollars to performance, the OS21RG is tough to beat!

http://www2.towerhobbies.com/cgi-bin...?&I=LXLU03&P=7