This part is from Stockalike Realism Overhaul
cost:
1800
mass:
4.0
category:
Propulsion
TechRequired:
advRocketry
engine_data:
normal_Ratio
{"isp"=>{"vac"=>390.0, "atmo"=>380.0}, "propellant_ratios"=>{"LiquidMethane"=>3.8, "LiquidOx"=>1.0}, "max_thrust"=>350.0}