YS 91 versus new OS SZ-H PS (pumped version with regulator)

[tp]

I couldn't help but start a good exchange--to those of you pilots that have tried the SZ-H PS, does it make more smooth, reliable power than a YS 91?

[Gary O]

I don't think anyone will really argue that the OS 91 is going to have more power than the YS. I run both, my YS's are super reliable, easy to tune and stay tuned. All of my OS 91's have the Kline reg. and Viperheads and they do have more power. I don't know about the new OS reg system. What I've noticed with my YS engines is I have to have better collective management. You can get away with a mistake moreso with the OS.

[Raptor Rulezzz]

I've had both in my R90's and the OS91SZ PS Hyper runs the same as the YS (smooth, consistent) but has considerably more power.

OS engines always had more power than the YS ones, but with the new SZ's (PS & std.) they also made a 90 that runs consistent :wink:

So far I really like my OS91SZ PS Hyper.

Cheers,

Rich :cool:

[bkervaski]

I've flown YS engines in two Evo 90's and my two new X-Cell's. I was unusually impressed with the amount of power the OS91SZHPS gave me at 8.18. Someone once told me and I agree, it's an "order of magnitude" more powerful than the YS.