CG Ultimate Engine suggestions?

Guys and Dolls:
I'm trying to chose an engine for the Goldberg Ultimate. I'm looking
for strong IMAC style performance. I want the vertical limit in my
hands, and not the engines.
Four stroke options seem to be the YS-120 (too expensive I think), or
a Saito or OS 120 - 150. Two stroke options,...OS 91FX, Webra Speed
120 pumped. I like the sound and power of four strokers, but the
simplicity of a good two stroker is nice as well.
I'm leaning towards the Speed 120 with a 16x8, because it's supposed
to be a very good match for this kit, and pretty quiet for a two
stroker, but it sticks out the cowl. I would like something that
stays in the cowl if possible. Will an OS 91FX have enough poop?
Can anyone share their thoughts and experiences?
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From that list, I'd pick a Saito 180. I haven't had one myself, but I've seen them run. Monters. Of course, you need a big fuel tank to go with it. :o)
I don't think so. I've had a 91FX. I liked some things about it. I had it on a 40-sized fun-fly styrofoam & aluminum plane--ah, I think it was a Duraplane model. It hauled the 7-pound plane around pretty good, but I never solved the remote needle valve problem.
An OS 1.08, if they still make them, would probably be more satisfactory. Or the Speed 120.
I've seen a YS 1.20 in the CG Ultimate. Pretty impressive. I don't know if it had unlimited vertical and you have to decide for yourself if you can live with the ... uh ... "features" of the YS system.
A friend of mine chose an OS 1.60 for his Dave Patrick ARF. He died, but not because of the engine/airframe combo. Another buddy bought the combo, but it hasn't flown yet. There seem to be a number of big engines (1.40 to 1.60) that have had some success in pattern competition. Webra makes one, I think.
Let us know what you choose and what works for you.
Reply to
Martin X. Moleski, SJ
Three engines I've used are the YS91FZ (8pound, 11ounce plane); OS1.08 - pumped with carb insert removed, and GMS 1.20 (9 pounds, 9 ounces). They all work well, although the YS has given problems that the others haven't. Vertical is limited to how high you can see. The GMS is new but is working very well and is the cheapest of the three. It's a fuel hog at this early point however, gobbling 16 ounces of fuel in 9 minutes at WOT. I like the performance of the YS the best but not by much. Given the lighter plane weight the performance is not a great deal different from the 120 as far as I can see. The engine has been a PITA though. It cost lots to begin with and needed an expensive repair before it would work right.
The heads stick out from the cowl. This is solved by looking at the other side. ;-)
John Hawkins - From Canada's Atlantic Coast
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Reply to
John Hawkins
I like that John. VBG It's always worked for me.
I was looking at the GMS 120 as well. It's available, well made and priced. With a fuel pump it might be just the ticket. I have a GMS 47 on a Somethin' Extra and love it. A bit finicky before fully broken in though.
Regarding everyone comment on YS. I tend to call em too expensive, not necessarily because of the up front price, but because of the care and burping they seem to need. I've never owned one personally (so have only second hand knowledge at best). Until they gain a reputation for being a bit less "high strung" and will eat KD instead of caviar, I probably won't. ;-)
Another fellow suggested the Saito 150 through email which is a good choice I think. Thanks Bob
I do like the four strokes, but this airframe is primarily intended for an IMAC newbie. (Me ;-) I'm still leaning towards a Webra 120 with pump. Nice power to weight, good noise level with a Bisson, reliable at any angle, and loves KD.
Reply to
I can second the Saito 150. I had an Ultimate with the 150 side mounted. It didn't need a take off roll. It would rotate to (near) vertical within 10-15 ft of the initial sitting spot.
It did produce a fair amount of vibration that required good support of the tail structure.
Have fun,
Reply to
Bob Eury
I had one that began live with a Saito 120S strapped on the nose. When it began showing signs of wear, I started to pay attention. When the 150came out, I ordered it and strapped it on instead. Lots and lots of fun. Sold the 120S.
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