Here are the 47# and 80# sheets. Had to zip them because .xlsx still isn't supported...
Values you need to input are filled tan. Other colors are there to visually represent important things like minPW, slope, static values from TunerPro, etc.
All voltages are assumed to be 14V for the sake of sanity.
Fuel is modeled to be ethanol blended 93 octane gasoline, non-winter blend, 5-7% ethanol content, with specific gravity of .740, 571.5623862cc/gallon.
The first 4 tabs only require values from the spec sheet from Ford, plus one cell you need to fill for 43.5#. The graph is there to help visually find the value needed, consistent with the overall shape. It will be very, very close. 39.15 and 50.03 are 10.88 apart and 43.5 falls about 45% of the way between the 2 points.
The VoltageOffset tab will automatically graph the Ford spec sheet points for 6, 8, 10, 11, 12, 14 & 15V, You need to flesh out the graph with the remaining values in the tan cells. Once satisfied, paste those 32 GM values into TunerPro. Hit the compare button to see what TunerPro does with rounding the values to its nearest increments (of about 15.267 - 15.3). Paste those values into column C. The graph in the LU47 and LU80 I've provided show the variation "delta" between calculated/ hand drawn data curve and how TunerPro rounds to the nearest increment of 15.3usec. TunerPro values are overlaid in red on top of the calculated and hand entered values in blue. Below 6V probably isn't important, even during cranking. None of my cars have ever turned over with less than 10.5 - 11Vbat on an extremely lucky day...
HiSlope and LoSlope tabs are much the same as the first 4, where you enter the Ford sheet values and craft a value for 43.5# with the assistance of the graph.
The PWAdder tab requires the most effort but it pulls almost everything needed from the other tabs. Primarily you deal with columns C and H. Column C represents the TunerPro 'Low Pulsewidth Adder' table. Columns A & G are the TunerPro xdf points with some added below 488usec to reach zero for graphing down to the offset. Orange below, green above, yellow on either side and red at the breakpoint. You need to add rows to create 1) the MinPW in ms and it shows the delivered fuel per pulse and how many cc/min that is, for the graph at the bottom; 2) the breakpoint fuel mass in both high and low slopes. This is the intersect between low and high slopes, which we will cross on the graph by offsetting the high slope until the breakpoint fuel mass in each column are overlaid on the graph. The offset, or time it takes for the injector to actually begin to open is built in, pulling from the InjOffset tab, using 14V and putting those values in column B.
Watch the formulas when you insert rows in and fill down the formulas on this sheet. Things like:
=(A11*LoSlope!D5)+(C11*LoSlope!D5) will increment "D5" to "D6" so make sure those 2 D5 stay D5.
=G7*HiSlope!D5 will do the same, so keep it "D5"
Columns E & J will be fine and preserve their formulas when you fill down or up the formulas (cc/min at PW "A" Lo and cc/min at PW "A" Hi)
"Bending" the low slope up to the high slope to get the offset values:
First, insert rows for offset and breakpoint (breakpoint mass on both Low and High slopes as noted above). Tweak the column A and G values for this to get it to match for 5 places to the right of the decimal point. The actual breakpoint mass at 43.5psi is noted below the Low table, in red. (Note - on either side of that, there are for reference, the low slope and high slope flow rates in cc/ms at 43.5psi).
Next, look at H3. It's something like =G3+0.xxxx, where 0.xxxx is the artificial offset we're adding to the Hi slope so it will intersect the low slope at the breakpoint. Just dial it in and fill down the formula =G3+0.xxxx from H3 to H36 until the red and blue data points for the breakpoint overlap. The zoom function in the View menu in Excel is very helpful between 200% - 300% for this.
Now that the Hi slope and Lo slope breakpoints overlap, we can start "bending" the Lo slope up until it overlaps the Hi slope line. Again, 200-300% zoom is great for helping you get the lines to overlap almost seamlessly. The idea is that when we convert back to usec for TunerPro's LT1 xdf we're no more than 10-15 millionths of a second off in calculations and the delta the xdf value increments produce.
Start entering values into C3, C4, C5 and so on, zooming and tweaking until the lines are almost seamlessly stacked, up to the breakpoint value, which will be 0.
I'm interested in looking now at the smaller injectors, in the 19# range for the sake of curiosity.
Disclaimer:
Again, I want to be clear that this is theoretical work and assumes my math modeling is correct and I haven't screwed anything up in Excel itself. Anyone and everyone with more math and injector science skills please chime in and help correct any missed assumptions or math, etc.
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