EFI Injector Duration Calculator

This simple little calculator gives the available time for an injector firing in an SFI (sequential) system. The cycle time for an injector firing is 2 crankshaft revolutions, and obviously the time per rev goes down and the engine speed increases. If you only want to know the length of time in milliseconds it takes for one revolution at a certian speed, just enter 50 in the duty cycle box. The default is 80 since that seems to be the accepted safe duty cycle for continuos operation.

Input engine RPMs:
Input the duty cycle (percent):
Available duration in milliseconds:

FORMULA:

duration(milliseconds) = duty_cycle * 120000 / rpm

The 120000 above is a constant that is derived from (60 seconds/min) X (2 revs/injector cycle) X (1000 milliseconds/second)

coolmail.gif 14.8 KScott Knight
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