Quote Originally Posted by Fast4.7 View Post
I do it by graphing the data points. My old TI-83 calculator does the job beautifully. I can graph the curve then pick the flow and offset multipliers at GM pressures. Then I graph the High and Low flow fuel delivery vs time with the offset added. That gives you the Short Pulse Limit. Then you are able to pick the time units along the axis and the difference between the graphs at the poing is the short pulse adder. Difficult to explain but easy to do. It is close enough that it runs very well. If it is a returnless system, I graph the offsets and flow at both ends of the table as well as the center and interpolate the rest.

I usually do it by drawing lines out in the sand with my finger.


No but seriously.. If your using ford data and your extrapolating it for GM use.. you are making a ton of assumptions. The ford data doesn't cover GM pressure.

One screen shot you can see some of the FORD tables being fitted for use in GM. Another screen shot you can see the FORD data vs the best fit GM data. You can clearly see the pressure ranges barely overlap if at all.

To say it's easy.. well maybe.. just depends on how right you want to do it.

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