What sort of RPM's would you guys expect from a 40 diesel turning an APC 12 x 6 prop?

Jim

What 40 diesel just out of curiosity?

if my memory is right my irvine 40 diesel turns a 12x5 wood zinger around 8700 its in an apache ll trainer if in error its on the low side apc plastics will turn 300-400 higher than
the wood zingers prop for prop

the irvine 40 diesels are good luggers I understand the OS40 conversions and a few of
the other modern conversions out perform it

I'm fooling with a Magnum Pro 40 with a modified RJL head. I doesn't have a lot of time on it yet. It is turning around 8,800-8,900. I'm running it with a control line venturi and spraybar. It flip starts readily at the running settings, and takes maybe 20 seconds to smooth out completely from cold. Havn't tried the muffler yet, but should make no difference. I've been running it on Davis 1/2A fuel which is what I have at the moment.

Jim

Jim ,I know that you are aware of this, but Davis 1/2A fuel is much too oily for the 40. you'll notice a definite improvement if you go to ABC blend.
I had done a comparison on the TT40gp glow/diesel. I know that i'd sent the results to Bob. I have them somewhere in the data file and will look them up. Was a comparison of about 10 different props. Dennis

Hi Jim! As you may recall, I was experimenting with 40-sized diesel stunt a year ago. I had to look up my log book on my PAW40 to get this info, but here it is, for what it's worth. On a 12X6 RevUp prop, using both the small (so-called "stunt") venturi and the large "regular" c/l venturi, I tried everything from 8.1K to 9.1K at launch. (These numbers come from an old Tower digital-read tach I've been using for years, and may only be useful for comparing performance using the same tach, although I have calibrated it in the past.) Anyway, I ended up shifting to an 11X6 Power Point prop and the larger venturi to get adequate power and fuel suction at the same time (higher revs, but higher fuel consumption, too). This is on Dr. Diesel's ball bearing mix. John

A few years ago, I managed 8900 out of a Davis converted FP 40 with a 12x6 apc. It slowed down the Big stick a bit, but the vertical performance was better then the 11x7 at 10500. Just to comparison shop.

Dave