This is a used engine I bought recently and cleaned up.

Powermaster 5/22 GMA
Rev Up 10x6
13,876 a bit rich of peak (TNC tach)
6.12lbs static thrust
1.18hp

David

Dave,


This was my first *real* glow engine...

It also had the Perry carburettor (later engines had HB's own excellent carburettor) and I remember it causing the heads of OS FSR and Webra Speed .40 engine owners to turn, because it out-revved their engines!


The manufacturer's claimed HP (PS) was 1.18, exactly your number (@17,000 RPM). Your engine realizes this exact output at a much lower RPM.


This engine has (had) a crankshaft with a crescent counterweight, which is rarely used in current engines; that I managed to break, by using a Sullivan starter on a hydra-locked engine...

Thanks Dar. My first real R/C engine (I grew up with countless Cox's like every other kid my age) was a K&B .40. I traded it for something or other and recently bought another just like it for nostalgic reasons.

I have read several times that the HB's like large props, and except for the Blitz's, are not high revving. I have never tested this claim, but it would make an interesting test. At any rate, all of my HB's start right away with a couple of hand flips.

David

Hello guys,

I am also the owner of several HB: HB 20 , HB 40 PDP , HB 40 PDP "Blitz" and HB 61 PDP.

I use Tornado 10% nitro with 16% synthetic oil in which I add another 2% castor oil. Flying field altitude is +60m from sea level. In thease conditions the engines rev as it follows:


- HB 20 (same as Veco 19, mine from the last series bought in 1986) with OS A3 plug and a Graupner Super Nylon 9x5 propeller revs 11.000rpm on the ground, not very good idle

- HB 40 PDP Perry carb (like yours with red PDP letters bought in 1980) with OS #8 plug and a Master Airscrew 11x5 propeller revs 11.500rpm on the ground and idles at 2400 rpm

- HB 40 "Blitz" (from 1983, PDP ported, black head, black PDP letters, chromed piston with standard ring, perry pump and carb) with OS #8 plug and TopFlite 10x6 propeller revs 13.400rpm and idles at 2700rpm

- HB 61 PDP (from 1980) Perry pump and carb with Enya #4 plug and APC 11x7 propeller revs 11.900rpm on the ground and with APC 12x7 revs 10.300rpm and idles at 1900rpm


All of my figures are somehow below factory specifications and other people's tests.

Have you tried with only castor oil in the fuel?

I wouldn't run anything else, they need the castor build up...