Johnny you will have plenty of power for that buggy with a 3port race engine.

the diference between the 3,5,7, race engines is the powerband, the 5 hits hard in the bottom and has good top end. the 7 has unlimited top softer on the bottom but still strong on in the mid range, and teh 3port is a kind of inbetween that is a good choice for buggy or truggy and a all around engine. you can use the powerbands to suit your car and driving style.

the 086 pipes do provide excellent performance for a great price on the engines but the 801 offers the same performance but does do better on fuel economy, thats its biggest strength.