I started with a MA 22x8 and Lawnboy 32:1 and was only at 6400-6500. When i swithced to the Vess 22A and 50:1 synthetic, Bell Ray, after tweaking the HS needle I was hitting 7400 on the ground. Broke my vess and reordered. Probably could have gone to 22B or 23A, but stuck wiht the 22A since it's a bi plane. I had more than enough power with the MA turning 6400. I have only about a gallon thru it at 32:1 and two tanks of the 50:1. Runs great and starts easy.