Got 7200 rpm on a 19*10 Menz.
First run, Krumscheid 1050 pipe.
Not that much I think.

Groeten,
Hans


Hans Meij / Modelvliegen

Those seem to be good numbers, Gerry Yarrish tests a P-51 in the latest MAN and uses that engine getting 6,900 rpm with a 20x10.

In the FMT, a german leading magazine, they did a comparison of a few smaller gassers.
For the ZDZ 40 with a tuned muffler they got:
18*8 9000
18*10 8100
18*12 7500
19*12 6900
20*10 6400
20*12 5600
21*10 5200

These number seems to be comparable to mine.
The RCS website claims 7400 on a 20*10
and the Amelung (German distributer) site claims 6900 on a 22*10
These are totally different numbers .

You better break it in and then you will see a difference. I have seed ZDZ's come up as much as 1000 RPM after break in. They keep on getting better right up to about 10-15 gallons