Originally Posted by vladconnery

What should be most in important in your descision is where you going to run your buggy I'm assuming it's a buggy. Short - intermediate tracks require more bottom and mid power. On A short track you rarely going to get your motor to wind all the way out so a 7 port would be a waist. A long track a with good straights you can take advantage of the top end speed of a 7 port. Just keep in minds races are rarely ever won in the straights.

RB S3 $189
RB S5 $229
RB's are just good motors long breakin though takes a gallon for them to hit there stride. But when you reach that gallon mark it's like a light switch gets turned on, They tun into a beast. With proper care they last a looooong time. My personal vote is for the RB it's what I run and have been very happy. Idles good right out of the box. Holds a tune too.

GO techs 3-7 port $209 for the 7 port
GO's are good engines good bang for the buck