Originally Posted by Chris Peralta

You don't want to tune these engines with a rich LSN, that will cause you flame outs after getting refueled. My WS7's LSN is normally between 4.5 and 4.75 turns out. That is generally close to flush or out from flush a little. The WS7 is more of a top end engine, I run a Losi buggy that comes stock with 13 48 gearing and I always changed out to 13 50 to get the bottom end I wanted, the engine still has plenty up top for long straights as well. Tune the engine so the bottom is nice and crisp and responsive. If after being on the track for 5 minutes or so you notice the low end power really falls off you can fatten up the bottom some.