[VM0824]

Ok I'm working through this one here. I have a data sheet for my frpp 47#er's.
all the info i have is http://www.fordracingparts.com/parts/ic ... 3-lu47.pdf

1. alosl and ahisl were easy to find.

2. for fuel_bkpt. i took the number 0.0000130700 and converted it to scientific notation which is: 1.307e5
i plugged that into fn398 (fuel - injector breakpoint) for all values, as i believe thats correct. however, in the description for the PID, theres some funky calculations going on. i believe the number i've been given was already lb's/rev. not mg/pulse, therefor i shouldnt need to do that right? also isnt it weird that the bkpt is so much lower than the stock one at 3.04?

3. fnpw_offset to fn367, pretty close to stock, just variations when i tried to fit the numbers in due to the value resolution (off by ~.02)

4. i found nothing for min_pw, so im guessing i dont use this guy

5. the rest of the four tables ending in comp im assuming are to be done by me if i were running a different pressure, but since im running stock regulator, i dont need these for everything.

i basically just need someone to confirm what ive done is correct.
thanks,
Vinnie

[decipha]

yep minus the breakpoint, the stock breakpoint value of 3.0398 is equivalent to .00001 so your breakpoint should be just a tad higher perhaps 3.973

[VM0824]

Is that what the calculations in BE were talking about? What units is .00001307 ¿ ? Would you mind explaining the math behind it?

[EDS50]

the correct breakpoint value would be 1.307. For the hi and lo slope take the advertised value from ford racing and multiply it by 3600. With that being said your hi lope is 46.818 and your lo slope is 51.5916. Input those numbers and the batt vs offset as advertised. If your running the stock fuel pressure of 39 then set all your fuel multipliers to 1.00 and you will want reduce your cranking pulswidth vs ect function accordingly.

[VM0824]

For the hi and lo slope take the advertised value from ford racing and multiply it by 3600.

yea i forgot to mention i did compensate for that. i took notice of the units and converted. got same results as you

If your running the stock fuel pressure of 39 then set all your fuel multipliers to 1.00

yea i noticed all these multipliers are weird values that have weird or crooked sharp functions. like "open loop multiplier vs act", "wot multiplier vs rpm". even "high speed multiplier" (which is .998 for all values :duh: ). i defnitely see how making everything 1.0 simplifies things

you will want reduce your cranking pulswidth vs ect function accordingly.

right! that also makes sense. great advice. thanks!

EDIT: I multiplied each value in crank vs ect by 0.404255319 (19/47)

[decipha]

Is that what the calculations in BE were talking about? What units is .00001307 ¿ ? Would you mind explaining the math behind it?

the .00001307 value is the lbs of fuel where the low slope supplies 100% fuel and the high slope supplies 0

the math varies with the function in the older ecu's, this was changed in the later strategies once ford realized it was pretty much useless and just overcomplicated things so they now have a scalar with a set breakpoint in lbs which is the value ford gives you on your data sheet for your injectors.

as i said before the stock breakpoint of 3.0398 in guf comes out to be .00001 lbs. There is no easy way to go from the function breakpoint to the set lb breakpoint, so one must use approximation

3.0398 / .00001 * .00001307 = 3.973

this won't be EXACT but it will be very close

[EDS50]

I dont understand the logic or benefit of using the breakpoint value for 19# injectors over the correct advertised breakpoint for any given injector. :think: All the advertised specs are out there and i just dont know why anyone would deviate from using them. Its practically dummy proof in my oppinion. As far as the breakpoint math there is no need to over complicate things, just move the decimal point 5 positions to the right and thats all there is too it.0.00001307 becomes 1.307. Its that simple. The minpw value is just a minimum repeatable pulswidth at least in the older strategies. It may have some minor contribution in the newer strats but thats about it.

[EDS50]

For the hi and lo slope take the advertised value from ford racing and multiply it by 3600.

yea i forgot to mention i did compensate for that. i took notice of the units and converted. got same results as you

If your running the stock fuel pressure of 39 then set all your fuel multipliers to 1.00

yea i noticed all these multipliers are weird values that have weird or crooked sharp functions. like "open loop multiplier vs act", "wot multiplier vs rpm". even "high speed multiplier" (which is .998 for all values :duh: ). i defnitely see how making everything 1.0 simplifies things

you will want reduce your cranking pulswidth vs ect function accordingly.

right! that also makes sense. great advice. thanks!

EDIT: I multiplied each value in crank vs ect by 0.404255319 (19/47)

Your approach to the crank vs ect math is correct. You may need to tweak it here and there depending on what the car likes.

[decipha]

I dont understand the logic or benefit of using the breakpoint value for 19# injectors over the correct advertised breakpoint for any given injector. :think: All the advertised specs are out there and i just dont know why anyone would deviate from using them. Its practically dummy proof in my oppinion. As far as the breakpoint math there is no need to over complicate things, just move the decimal point 5 positions to the right and thats all there is too it.0.00001307 becomes 1.307. Its that simple. The minpw value is just a minimum repeatable pulswidth at least in the older strategies. It may have some minor contribution in the newer strats but thats about it.

those breakpoint values are in a set lb of fuel value, the guf ecu DOES NOT HAVE A SET LB FUEL BREAKPOINT VALUE, a breakpoint of 1.307 comes out to be about .000002325 lbs of fuel which is about a quarter of the published ford specs for your injectors

it's not as simple as moving just moving the decimal over, its two completely different calculations

[EDS50]

I dont understand the logic or benefit of using the breakpoint value for 19# injectors over the correct advertised breakpoint for any given injector. :think: All the advertised specs are out there and i just dont know why anyone would deviate from using them. Its practically dummy proof in my oppinion. As far as the breakpoint math there is no need to over complicate things, just move the decimal point 5 positions to the right and thats all there is too it.0.00001307 becomes 1.307. Its that simple. The minpw value is just a minimum repeatable pulswidth at least in the older strategies. It may have some minor contribution in the newer strats but thats about it.

those breakpoint values are in a set lb of fuel value, the guf ecu DOES NOT HAVE A SET LB FUEL BREAKPOINT VALUE, a breakpoint of 1.307 comes out to be about .000002325 lbs of fuel which is about a quarter of the published ford specs for your injectors

it's not as simple as moving just moving the decimal over, its two completely different calculations

The gufx value is lb/rev. Is the 2 different calculations due to the fact that the offset is also used in the calculation as a pulsewidth adder?

[VM0824]

like a boeing 747. this is way over my head

[Green-Jimmy]

Is that what the calculations in BE were talking about? What units is .00001307 ¿ ? Would you mind explaining the math behind it?

the .00001307 value is the lbs of fuel where the low slope supplies 100% fuel and the high slope supplies 0

the math varies with the function in the older ecu's, this was changed in the later strategies once ford realized it was pretty much useless and just overcomplicated things so they now have a scalar with a set breakpoint in lbs which is the value ford gives you on your data sheet for your injectors.

as i said before the stock breakpoint of 3.0398 in guf comes out to be .00001 lbs. There is no easy way to go from the function breakpoint to the set lb breakpoint, so one must use approximation

3.0398 / .00001 * .00001307 = 3.973

this won't be EXACT but it will be very close

I'm using the 39lb -M39 injectors. They show a breakpoint of .00001526 on the datasheet- should I be setting the breakpoing to 4.639?

3.0398 / .00001 * .00001526 = 4.639

I was doing the same thing of just moving the decimal over 5 places using that ( 1.526 e-5).

-Jeff

[decipha]

yes jeff your math is correct