My TH .75 is turning a APC 12/8 at 11,400 w/Slimline pitts on WC 10%, and this is flying Rpm not peak. My GP Shoestring hauls A** with this set up. I could not ask for any better performance. I have been asked several times about the power plant in my plane. Some people in the club just cannot get over the fact that it is a $85.00 engine from Tower.