<tat> anyway an ace pilot of Zero wrote:
<tat> When you finish climbing and go to cruise mode,
<tat> decrease throttle so boost shows -200mmHg, (22.05 inHg)
<tat> and then start pushing the pitch lever gradually, carefully monitoring rpm and speed.
<tat> while pushing the lever, the rpm decreases but the boost increases to -100mmHg(26.98 inHg), which means the pitch is increasing
<tat> when the engine RPM drops to 1850 (1272 prop rpm), Zero's speed is stable at around 130 kt, the most fuel efficient speed.
<tat> when you climb or in a combat, you need to bring the pitch lever back to 0 position.
<tat> while you're flying at 1850 engine rpm (at full pitch), you cannot reach to the max speed even with full boost.
<tat> and you can adjust the speed by pushing and pulling the throttle. the pitch changes as the throttle changes, but the engine rpm stays the same.
<tat> so this is how the Zero's constant speed prop works.

Today I built a JSBSim script that starts at 2550 RPM and 35.8 inHg (+150 mmHg) at 110 knots. It is allowed to accelerate for 20 seconds then the 
manifold pressure is reduced to 22 inHg (-200 mmHg) it begins to decelerate until the RPMs are reduced to 1850 at 35 seconds. Unfortunately 
the manifold pressure does not rise. Manually setting the manifold pressure to 27 inHg (-100 mmHg) holds speed of 135 knots in level flight.


<tat> Fuel: Aviation fuel 92 
<tat> Density: 0.735 kg/L  @ 15 deg-C
<tat> Octane: 92
<tat> Fuel Pressure: 0.25 to 0.35 kg / square-cm
<tat> Cylinder temp: 200 deg-C
 

[tat] Fuel consumption (Liter per hour)
[tat]   Normal-Use (+50mmHg) : 245 L/hour 
 [ron]    0.1143 lb/s
 observed 0.1931 lb/s, 704 hp@2200 RPM 12000ft
 re-tuned 0.1189 lb/s, 708 hp@2200 RPM 12000ft
[tat]   Typical:  (+150mmHg) : 322 L/hour
 [ron]    0.1449 lb/s
 observed 0.2320 lb/s, 830 hp@2400 RPM 12000ft
 re-tuned 0.1430 lb/s, 860 hp@2400 RPM 12000ft
[tat]   Take-off: (+250mmHg) : 390 L/hour
 [ron]    0.1755 lb/s
 observed 0.2740 lb/s, 1030 hp@2550 RPM 12000ft
 re-tuned 0.1687 lb/s, 1030 hp@2550 RPM 12000ft