RE: YS 1.10 vs. O.S. .91fx for Funtana 90s?
If Kyle had to add 3oz of weight with a YS-120 then you would have to do the same with the Saito 180 considering the Saito weighs 31oz and the YS weighs 31.2oz. It also has to do with preference, some like it nose heavy for landing, and some like it tail heavy for "hanging" on the prop. Besides, he was probably still within the CG range with or without the 3oz. As for "dead" weight, any weight is dead weight in an airplane. The YS will let you move your gas tank anywhere you want it to control balance, where as with the Saito it needs to be behind the firewall. Here is some other specs to compare. YS RPM 2,000-12,500, Saito-2,000-10,000. YS-16X8 prop @ 10,500, Saito 16X8 prop 9,400. YS pressurized fuel system won't lean when hanging or richen in nose dive, Saito exhaust pressure nuf said. Please keep in mind these are not my personal specs, but what I've been able to get from many searches on the net from companies and personal testimony. From personal experience with both a Saito and YS, the YS definitely has a quicker throttle response. Saito is a lot easier to tune and is maint free once properly broken-in which is why alot of people like them. I've found many people are not mechanically inclined and a YS does require you to keep on top of it. Which is why I get such great deals on "barely" used YS engines, they just can't get the hang of tunning them.
Mike