ORIGINAL: cmoulder
Interesting report on the fuel blend - sounds extremely promising!
I can't believe how expensive that AVGAS is!!![X(]
Oh, wait, 30% nitro glow fuel is how much??
My SAP 180 is working so well with 89 octane pump gas that I am loath to mess with it, but wondering how much better it would be without the 10% ethanol. I have a marina nearby and seem to recall reading or hearing that boat gas doesn't have ethanol.
As my funky schedule has it, I am off tomorrow and flying (the wind is forecast to subside) and will try the 16x12 pattern prop, and perhaps some 93 octane pump gas. I have a spare 1-gallon fuel container that happens to be empty at the moment.
OK, well, it is very satisfying to see that we have a totally working and mimimal-maintenance setup and have the luxury of experimenting a little.
I would venture a guess that we will see a LOT more of these engines in pattern next year!
Bob,
I am very interested in your findings with 93 octane pump gas. I don't think the engine will have any problems with the 16x12...it turned the 17x12 at least as well as any other 2 stroke I've had and definitely a little more rpms than I wanted. Temptress is rather low drag airframe so it picks up speed fast.
I have a 16.5x13 apc from 8 or 9 years ago that I used on the webra 145 and 160 during break in. I don't really want to go to a 13" pitch (maybe on the 3 blade) because speed gets a little out of control. Had that problem with the glow 2 strokes too. The SAP actually outrevs the glow engines which just means even more speed. Sound would be very nice though so it's just another experiment.
I may have found the problem with sagging when turningthe 18x12 hybrid...I think the vent was getting blocked just enough to cause a problem. Regardless, that prop trimmed to around 17.5" should work fine. Yet another experiment.
Electric is making great inroad into pattern as I had predicted 7 or 8 years ago when I saw an early large electric model perform with early lipos. No it wasn't Jason Shulman...he came about a year after that. Now I hear that you can buy a 10s set of Zippy lipos for pattern at under 90$. And guys are reporting at least 40 cycles so far. Point is that electric pattern is finally competing well with some wet power set-ups regarding cost. However, the SAP engine with it's lowest costs all around will probably never be equaled. Cost per flight is..what...15c per flight?? Also, I think that when guys see how easy the table manners of this engine are they would possibly consider it. Just love those 1 flip starts. Just the ticket for me since I hate starters
BTW I decided that I will attend next Saturday's contest. Hope to see you there