Horsepower Calculator

"How hard could it be, there's only three of them right?"

All three of these injectors work well at low pulsewidths, have a very broad linear operating range, and will work across a wide range of fuel pressures. This makes them particularly versatile, but it also causes some confusion as to which injector to use for a given application.

Deciding between the ID725, the ID1000, and the ID2000 is not all that hard, but the calculator lists the power potential of all three injectors in 5 psi increments across their operating range.

Because our flow testing is done with gasoline, the flow numbers will relate directly to the horsepower potential of the injector. The results include the effect of dead time, and maximum duty cycle which is a function of the injector's recovery time.

If you are testing on an engine dyno with an accurate fuel flow meter, you will find that the predicted horsepower is spot on.

If you are testing on a chassis dyno, you will have to account for drivetrain losses. There is a great deal of controversy surrounding drivetrain loss, and to be accurate a bit of experience is required. For what it's worth, my own testing has shown that the Dynojet brand reads quite close to flywheel horsepower, with every other brand reading considerably less.

The calculator is a Microsoft Excel spreadsheet so you will have to have Microsoft Office installed on your computer. You can either left click on the link to open the spreadsheet in your browser, or right click to save it to your hard drive.

I hope you find this helpful.

PY

Injector Dynamics Horsepower Calculator