I got a question about two engines and i need some help. I was wondering what the differnce is between he OS .70 ultimate and the OS .70 surpass. what one would you buy. pros, cons etc. the reason im asking is because i have noticed alot of people recomending the .70 surpass and stuff but i look on the great planes website and it recomends the .70 ultamate and also on the OS website i was looking at the two engines and the Ultimate is smaller, has a full pump and just looks like a all around better engine. so i was just curios why people recomend the surpass and I havent read alought about the ultimate.

I don't know anything about the OS 70 Ultimate four stroke, but I'm guessing the reason you always hear about the Surpass is because it's been around awhile. I'm also guess that the Ultimate is a new engine.

The Surpass is a good reliable engine if that helps.
Dennis-

I had never heard of it either, so I just did a Google search for OS 70 Ultimate.

WOW!

Can't wait to try one!

http://www.osengines.com/engines/osmg0875.html

I looked at the Tower site, and they sell 3 versions of the OS 70 fourstroke. The original is about $190, the version II is about $210, and the Ultimate is about $300.

If I was to be choosing one, I would think about whether I needed a pump or not. My fourstrokes are usually mounted with the carburetor about mid-tank height, so I don't need pumps. The extra $$ would probably push me toward one of the others, but you may have reasons to use the pumped version. For instance, the pumped Ultimate is cited as having measurements a bit shorter than the earlier version. If you had a particular cowl measurement that might enclose the Ultimate but not the earlier version, that might be the decision maker.

Good luck,
Dave Olson

oh some on can somebody who has this engine help