My RPM when at fully decreased throttle (F2) is 1848 rpm on a psiton engine max rated at 2800 rpm. How and where do I lower that, to say around 500 RPM ?[piston_engine]power_scalar =1.00000cylinder_displacement=58.75000compression_ratio=6.720000number_of_cylinders=4max_rated_rpm=2800.00000max_rated_hp=115.00000max_rpm_mechanical_efficiency_scalar=1.00000idle_rpm_mechanical_efficiency_scalar=1.00000 max_rpm_friction_scalar=1.00000 idle_rpm_friction_scalar=1.00000[propeller]propeller_type=1

My RPM when at fully decreased throttle (F2) is 1848 rpm on a psiton engine max rated at 2800 rpm. How and where do I lower that, to say around 500 RPM ?[piston_engine]power_scalar =1.00000cylinder_displacement=58.75000compression_ratio=6.720000number_of_cylinders=4max_rated_rpm=2800.00000max_rated_hp=115.00000max_rpm_mechanical_efficiency_scalar=1.00000idle_rpm_mechanical_efficiency_scalar=1.00000 max_rpm_friction_scalar=1.00000 idle_rpm_friction_scalar=1.00000[propeller]propeller_type=1

In the piston engine section you want to adjust this line,idle_rpm_friction_scalar= 1.0 the default is one. increase the fig 1.2 for example to reduce RPM or decrease 0.8 as example to increase RPM.good luck,Douglas

I'll give that a try and hope that there is enough cooling for the extra heat :(

I'm pretty sure there are other setting regarding the prop that can affect idle RPM. Number of blades, prop diameter, blade pitch, and prop MOI...

That worked great for idle.Another question - The engine will only reach 89% of RPM, normally, so I scalared the max RPM to 0.1 and that brought it up to 96%. How can I increase the top end to say 115% ? I'll add the prop info in case somehting is way off there.max_rpm_friction_scalar=0.10000idle_rpm_friction_scalar=1.75000 propeller_type=1propeller_diameter=5.70000propeller_blades=3propeller_moi=3.72371beta_max=18.00000beta_min=16.00000min_gov_rpm=0.00000prop_tc=0.10000gear_reduction_ratio=2.43000fixed_pitch_beta=17.00000low_speed_theory_limit=80.00000

The value you can adjust might be,max_rpm_mechanical_efficiency_scalar= 1.5 1.0 is defaultDouglas

Thanks - it seems that the for:Reducing IDLE RPM:adjust upward the friction...idle_rpm_friction_scalar= (greater then 1.0)Increasing MAX RPM:adjust upward the efficiency...max_rpm_mechanical_efficiency_scalar= (greater then 1.0)