Nitro and rockcrawling don't mix. They don't have the instant torque that electric does, they have clutches that will probably burn up super fast when trying to climb a wall, it would be pretty hard to get the gear ratios low enough to have it even perform good. I would say make the revo brushless and do what steve slayden did with his revo. Yes his revo is nitro but a brushless one would so beat a nitro one. Nitro engines also load up at idle.