I have an HPI rs4 pro with the os .26sc in it. I'm trying to sell for 150.oo. The car is geared proper and is in line with the 2 strokers. The only downfall is motor size doesn't allow you to use a 2 speed tranny. If you want 1 I got 1 ! They sound cool and perform the same. As I said it's for sale so I can get more giant scale planes. If interested my email is [email protected]