When I got home I looked into an engine swap on my Pizazz. I pulled the OS 70 Surpass II off the Pizazz and compared it on a scale to the Saito 91 I bought at the swap shop. It's hard to believe, but the Saito 91 was actually about 1/4 ounce LIGHTER, and it fit directly into the same mounting holes as the 70 Surpass. I found that the Saito 91 is a very bored out Saito .65. It's lighter than both the Saito 65 and the Saito 80. The HP ratings are 1.1 for the OS 70 and a whopping 1.6hp for the Saito .91, a 50% increase with NO weight increase. I put a 14 x 4W prop on it, swapped out the gear and wheels for a little taller one, and I'm still at the same 5.5 lbs on my Pizazz. Holy cow, I can't believe that Saito 91 was lighter than the OS 70. I know the OS 70 is not considered light and the Saito .72 is three ounces lighter than it. OS should put their engines on a diet. If Saito can do it why can't OS? Now I will have ROCKETING POWER in the Pizazz. I have Pinhead to thank for the idea, he told me over the weekend that he wanted a Pizazz with a Saito 91 on it. I thought that was too heavy until I looked into it. Luckily I had a Saito 91 that I picked up NEW at the local swap meet for $150. I can probably sell the OS 70 for that and break even.