[dcb]

Can't compute RPM till you know how many injector pulses there are per revolution.

Maybe quick setup is a list of questions,

1. how many cylinders do you have?
2. Is your car TBI (one or two injectors just by the throttle body)?
3. make an initial guess at your mpg at 50mph
4. how big is your tank
5. calibrate speedo/injectors, accelerate to exactly 50mph on level ground in no wind, press select and maintain 50mph for 10 seconds.

calibrate will take the number of vss pulses received in the next 10 seconds and use that to determine the vss pulses per mile. (multiply vss pulses by 7.2)

calibrate will also try to match the injector flow rate with the amount of fuel that would have been required at the estimated mpg for those 10 seconds at 50mph.
flow rate: ((10/72)/estimated mpg) gallons/sum of injHI time as minutes. This should get trued up at fillup time.

Or we make some initial guess on the flow rate based on the car or vin or?, and/or slap a web utility to give people a list of setup items, or?