… by Experience & Gut Feel Throughout the racing community, experience and gut feel are the most common methods for the selection of nozzle and jet size numbers for setup and tuning of mechanical fuel injection. It is a form of iteration or ‘connecting the dots’. Given enough time and expense, experience from good and […]
Throughout our publications, air intake and fuel delivery values are converted to a ‘uniform standard of units’. That is “pounds per revolution”. The tuning demands for weight of air and weight of fuel become easy to understand, record, and analyze with that numerical value. And easy to change in fine tuning increments with this simple […]
We used a simple fuel pressure gauge with a peak hold needle to record our highest fuel pressure value from a run. The gauge is an all stainless, bottom 1/4NPT pipe, glycerin filled gauge with a maximum indicating needle. Glycerin filling is needed to dampen the needles from racer vibrations. Stainless is needed for resistance […]
An Advanced Method in fuel injection tuning for certain normally aspirated (NA) engines is to flatline the fuel curve. Flatlining is not always possible, especially in very high flowing cylinder heads or efficient pent roof heads on small displacement engines. However, in race engines with common wedge heads or early model Hemi heads, volumetric efficiency […]
Different designs of inlets and outlets dramatically effect the performance from Roots superchargers. Original designs for non-boosted flow used large inlet and outlet openings. Shrinking those openings for boosted flow improved performance by reducing reversion
Lastest from a reliable dyno source is about 80 horsepower per psi of boost added from ram air.
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Use Pro-calc to run your fuel injection jetting prior to a flow bench test, dynamometer test, or race outing.
The determination of nozzles & jetting in a new fuel injection setup can be a challenge.
We dropped the AFR to 3.2 The idle went up by 300 RPM over the 9% setup (with no idle adjustments).