ORIGINAL: gkamysz
Dave, how many prop power calculators have your tried? I'm certain the spread sheet I've been using for 15 years is accurate. I tried several other calculators after you were so adamant, but the math is simple and even with pen and paper I get the same result. One last try on my part. Download Pe's latest version of his site and browse through the other pages, you'll find a prop curve for Xoar props, that puts the 20x10 at about the same as I say, and engine testing of the MVVS 80cc turning a
24x10 at 6630 making a little over 7HP.
Dave, I know you think I have some vendetta against diesel, I'm just an engine fanatic, and I know incorrect figures when I see them. I have many figures saved from those I deem credible to get an idea of what engines are capable of. Every one of these is backed up by calculating the BMEP, which double checks the figures for sanity. it's not rocket science, and BMEP or torque calculations always blow the lies out of the water, in any engine discussion.
Once again, tell me these are wrong.
I have a 30cc in my CMP Spitfire. I have used
20X10 Zinger 6800rpm (way to big)
[link=http://www.rcuniverse.com/forum/m_10614748/anchors_10614748/mpage_1/key_/anchor/tm.htm#]Post.[/link]
I am really surprised at the power of the DLE 30.
with a Menz Ultra 20x10 wood prop at 7140 rpm, 90.6db;
[link=http://www.rcuniverse.com/forum/m_8885257/mpage_97/key_/tm.htm#]Post.[/link]
If the ST4500 is so strong why does a 30cc gas outperform it?
I've invited Pe to have a look at our figures.
Greg