two stroke or four stroke power?
 

I am building a 60-90 Extra330s and I am trying to decide on power. Any ideas on what might work best is welcome. THe plane weight is 3400 gr (7.5 lbs) has a 63.8in. wing span and is 53.6in. long. I want to try flying it 3D more than sport. The manual recomends a 60-91 two stroke but I was thinking of a 90-1.20 four and swing a larger prop.....any thoughts? Thanks,Tugboat.

RE: two stroke or four stroke power?
 

four stroke will feel like it has a broader power band unlike two strokes which will feel like they have a very limited power band. In my opinion a saito 125 would be the best engine for it with a 16x6 apc prop on 30% nitro or a 15x7 apc prop on 15% nitro. If you go 2-stroke the 91 will not be enough for 3d, a 120 2-stroke would be the only other option and they are heavy.

RE: two stroke or four stroke power?
 

I would go with a YS 110FZ for 3D since it has instantaneous throttle response, lighter yet more powerful than most 1.20 size four strokes, including the Saito 125. Plus, you can mount the tank over the CG to avoid trim changes as fuel is being consumed.

RE: two stroke or four stroke power?
 

4 stroke all the way.. Once you go 4 stoke you will never come back to the 2 cycle. Plus the sound is something to adore.
While the YS 110 is a very nice motor and powerful, they could however, be somewhat a pain to tune. Im always watching people at my field trying to fiddle with their needles on their YS's. But, I can say that once they get it set, there is a lot of power . I myself is using the Saito 125 while its just shy of putting out the power of the YS, i dont have to fiddle with the needles everytime im at the field.

in other words. 4 stroke at the way!!

RE: two stroke or four stroke power?
 

Saito 100 on 30% heli fuel. Big power without alot of hassle.

RE: two stroke or four stroke power?
 

Five YS 110's, two YS 120FZ's, one YS 140 Sport, three YS 91's, one YS 63FZ, and YS 63S on YS 20/20 fuel for three years now. Outrageous power, instant throttle response, zero bearing failure, zero deadstick, zero hassle, zero needle fiddling.

RE: two stroke or four stroke power?
 

Thanks to all who replied! Although I still have not chosen an engine, I am certain it will be a four stroke. After talking to the guys at my flying field, and those of you who replied, it seems to be the right way to go. I am thinking it will be the Saito 100. Tugboat.

RE: two stroke or four stroke power?
 

Spend the extra and get the 125, you'll be happy you did.

RE: two stroke or four stroke power?
 

saito 100 is great for overpowering 40 size planes but will not cut it for 3d on a 60 size plane. My uncle has a 100 on a pacific aeromodels 60 size edge 540 (7.8lbs) and hardly flys the plane because it is underpowered for any type of 3d, while I have a 125 on the ultra stick 60 and it is a blast to fly with power to do anything imaginable, even a vertical hand launch without any feer or effort. I have it with a 15x7 prop on 15 nitro with a 24 ounce tank mounted on the cg and no muffler (using a t on crankcase for pressure).

if you have decided on saito go for the 125 even if you have to save money to get it, it weighs only 3 ounces more than the 100 but has much more power.

RE: two stroke or four stroke power?
 

If it were me, I'd skip the Saito 100 and go with a YS 110.