I had a 4 mill oem dune play port from F.A.S.T years ago. It has pwk 35s, cpi pipes and it was a perfect motor for trails. Sold it for a Redline 4 mil serval and didn't care for it. Then went to a 10 mill redline ported cub. The 4 mill dune play port was a dam good motor and better then my 4 mill serval.