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LastCall
November 21st, 2011, 08:34 AM
I added 60# injectors (well 69 at 4 bar) for my truck. I plugged in the figures into a spreadsheet to get the IFR values at the various map pressures. I have included them below:

MAP (PSI) LB/HR
10.05 69.28325412
10.11 69.71504837
10.17 70.14418464
10.24 70.5707114
10.30 70.99467569
10.36 71.41612314
10.42 71.83509806
10.48 72.25164345
10.54 72.6658011
10.60 73.07761161
10.66 73.48711443
10.72 73.89434793
10.78 74.29934942
10.83 74.70215521
10.89 75.10280062
10.95 75.50132005
11.01 75.89774699

Here is the date the injector company provided me:

Static Flow Rate: 625-630cc/min at 43.5 PSI
Dynamic Flow Balance at 50% Duty Cycle/6000rp 5ms at 43.5 PSI: 285cc
Coil Resistance: 12.5 Ohms
Latency (dead time): 0.5 ms at 14 volts

Besides updating the IFR table, what else needs to be updated?

Any help wpould be greatly appreciated!!!

joecar
November 22nd, 2011, 04:33 AM
The cc/min value has to be converted to g/min by multiplying it by the fuel density (g/cc), I need to look this up for the fuel you're using.

Then it would have to be converted to g/s or lb/hr (whichever you prefer; I prefer g/s).

Then it would be scaled for pressure by multiplying by sqrt(58/43.5).


Also, if you have a manifold referenced FPR, then the IFR table will be flat same value all across.

You also need to update the other injector tables from the other values on the injector specsheet, this is a little harder.