chances are you guys probably already know these by heart, but this is my (weak) attempt to make a useful contribution...Piston speed = stroke x 2 x RPM / 12
Port velocity = (bore^2/port_dia^2) x mean piston speed
CFM = 3456 / (C.I.D x RPM [max]) **this formula assumes 100% VE**
CFM = ( cid X .5 X Ve X rpm ) / 1728 (use 1.0 for 2 stroke engines)
Cubic inches =Cubic Centimeters/16.387
Injector sizing (in cc's) = (HP x BSFC x 10.5) / (# of injectors x Duty cycle)
Injector sizing (lb/hr) = (HP x BSFC) / (# of injectors x Duty cycle)
Max inj. HP (lb/hr) = (flow rate x # of inejctors x .
/ BSFC
Max inj. HP (CCs) = (flow rate x # of injectors x .
/ (BSFC x 10.5)
Flow rate(modified) = (sq.rt of new rail pressure/old rail pressure) x old flow rate
BSFC = lb/hr of fuel / BHP
Fuel requirement = Horsepower x BSFC
Lbs/hr = HP x .5
GPH = Lbs/hr / 6
Pressure = V^2 / 57,600 (bernoulli's principle. v=velocity)
for turbo
Pressure ratio =Pb+Pa/Pa (pa= atmospheric (14.7), pb= boost)
PR=(14.7 + psi ) / 14.7
CFM = [(DxCIDxMAX RPM)/1728]xVExDR
CFM = L x RPM x VE x PR / 5660
Boosted CFM = PR x CFM
Turbine trim = [ (inducer^2) / (exducer^2) ] x 100
thats all for now. if i think of more, i'll put em up.
