FWIW, here's some thrust numbers I got off my DA50's last night. Both engines are broke in, Slimline Pitts mufflers, and running Mobil MX2T oil at 32:1. Temps were 80 degrees or so, low humidity. Thrust was measured with my digital fish scale.

Bolly wood 22 x 10 turning 6600 pulled 23 lbs + or - a bit

Bolly wood 23 x 8 cut down and balanced to 22 x 8 turning 6780 pulled 23 lbs. + or - a bit

The 23 x 8 uncut was only turning 6300 and I didn't like the flight charactoristics at all. Too slow and too much load on the DA IMHO. It works great on my WH 28% Edge cut down to a 22 x 8.

Nogyro,
Which one do you prefer now?, the 22x10 or the 23x8 cut down to 22x8. Do you have any thrust numbers for the 23 x 8 @ 6300 RPM?.
Andres

I like the 22 x 10 on my WH Extra, and the cut down 23 x 8 on the WH Edge. The Edge has quite a bit more drag on it than the Extra, so the lower pitch really isn't noticed. I prefer the Extra hands down for IMAC. It tracks much better than the Edge, but you can't beat the Edge for 3D. The straight leading edge really has the extra lift to it. My Edge is just a few ouces lighter than the Extra, but it flies much lighter and will really slow down to land. For some reason, I can hold it in a TR better than the Extra also. The thrust really is that close between the props, both planes are almost identical in vertical performance, the 8 pitch really lets you slow the plane down for in close, low and slow manuevers, more so than the 10 pitch. The 8 pitch just didn't present the plane well for IMAC. Just a tad too slow.

Sorry, I didn't get any thrust numbers on the 23 x 8 before I nipped the ends off it.

Ouch. Only 6780 RPM from the great DA 50. I got 7100 RPM from my Brison 3.2 with Menzs 22x8 on Bission pitts muffler.

I never tried a MenzS 22 x 8. Bolly and Menz props are similar, but yet different. I'm sure the loads are quite different.

My DA turned a MenzS 22 x 10 at only 6100, but yet the same engine turned my Mejzlik 22 x 10 at 7200.........

Yep, rpm bragging only counts if everyone uses the same size and brand of prop..

My DA 50 turns that prop at 7200.....so there!

I am so happy i dont have a tach

And another update on the motor on 2 gallons or so? No thanks

Mine too

Game...Set...Match.

LMAO....I think the point to be made here is not that the DA 50 is some uber GREAT engine but that pretty much any of the brand name 50's will make similar power on a given prop.

Where the DA stands head and shoulders above the rest is in the customer support provided by DA themselves. I have no personal experience with any of the other brands like BME, Brison or ZDZ but I have read of MANY satisfied customers that own them and I think that is great. Will I buy one of them myself? Probably not, because I am totally satisfied with my DA and they have my engine business for any of my future GS projects. That decision is based completely on my experience with DA's customer service thus far that has been above and beyond that of any other hobby manufacturer I have yet dealt with.