Fuel injector Sizing Program by Bowling

This program allows you to determine the correct fuel injectors to use based on a few engine parameters. Two different programs exist - one computes the operating rate for a given injector size, and the other determines the injector size (in Lbs/hr) based on maximum RPM at Wide-Open-Throttle (WOT).

Input your Engine Cubic Inch Displacement (CID):

Input the Engine's Peak Volumetric Efficiency (%):

Input the Engine's RPM at Maximum Torque:

Cylinders: Four, Six, Eight, or Twelve

Enter Injection Mode:

Desired Air/Fuel Ratio:

Injector Size (Lbs/hr):

Want to Compute:

Press this button to submit a computation:

To reset the form input:


The following equations were used:
w = cid * ve * 4.428e-05
wpc = w / ncyl
s = wpc / af
f = injec * (1./3600000.)
time = s/f
maxsquirttime = 60000./rpm
duty = 100. * time / (2.0 * maxsquirttime)
bestinjector = (s * 3600000.)/(2.0 * maxsquirttime * 0.8)

Bruce Bowling
Bowling Superior