ok i know this is a nitro thread but i dont know what makes a tuned pipe have more horse power cus i wand to make a cutom one for my weed eater r/c i hear u want a big hole to start wit then go to s skinny hole so it has more compression please help

A tuned pipe doesn't increase your engines compression....the expansion chamber causes a exhaust boost via pressurizing the exhaust and removing it more effectivly which results in power gain..depending on size of expansion chamber and length of pipe determines power gain from it....you can purchase ready made tuned pipes at Oneill Brothers.[link=http://www.oneillbrothersracing.com/]Oneill Brothers Racing[/link]...and yes they do increase low end to high end and that'd give you a faster hole shot....also if its a weed wacker engine ya should be posting here.

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