PMD resistor

[Bluevee33]

I just ordered and installed a new PMD! It didn't come with a resistor, I did order a new #9 resistor and it should be here by Monday afternoon.. It shouldn't notice there is no resistor for 50 starts right?? It should be okay for me to drive to work and back and not go into limp mood for not having a resistor? Thanks
Robert

[grancito]

I understand that it will set resistor 1 not limp mode.

[Bluevee33]

With the resistor 1 setting will the truck still run and drive fine?? Thanks all

[grancito]

Will run fine, just a slight drop in power, you may not even notice it.

[Bluevee33]

So you say I may not even notice running nothing besides mileage goin down.. Will I even notice anything now I have the #9 resister and it kicks in??

[jifaire]

Same answer. If you don't notice it setting back to a #1, you won't notice it setting forward to a #9.

You'll just push a little harder to get the same thing.

What # was your old calibration resistor, by the way? You can fish it out of the old PMD with a paperclip with a hook in the end.

[grancito]

A 1 resistor will give you less fuel at full throttle, the 9 will give you more fuel at full throttle and therefore a bit more power than the original that may have been a 5,6 or 7.

[Bluevee33]

No idea what was in there! i didn't even pull out the old PMD! Just left it on the IP! It's not that big of a deal, just hoping it'll give the truck a boost!!

[grancito]

If it had 6 resistor before and you put in a 9, you should get 6% more power.

[jifaire]

If it had 6 resistor before and you put in a 9, you should get 6% more power.

FSD Calibration Resistor Values
Resistor No. ........Ohms .................Fuel Change MM3/ 1000 Strokes
1............. .........4300-4500 ............................-4
2 ......................7200-7400 ............................-3
3 ......................9800-10100 ...........................-2
4 ......................13100-13500 .........................-1
5 ......................17500-18000 ..........................0
6 ......................27700-28300 ..........................+1
7 ......................43700-44700 ..........................+2
8 ......................58400-59600 ...........................+3
9 ......................79800-81400 ...........................+4

Not according to this chart... if you had a #6 and you put in a #9, you would gain from +1 to +4 cubic mm, or 3 cubic mm.

On an Hot-shot IP that puts out 91 mm^3, that 3mm^3 is gonna be 1/30 of the Max output, or about 3% at Wide Open Throttle.

And you will only see that at full rated output, flat on the floor...

A #9 resistor is hardly worth the effort, depending on what calibration you have in there now.

It's slightly more than 1% per resistor number on a WOT pump.

According to the experts,
"A resistor is used to calibrate the IP fuel delivery to test specifications to accomodiate wear or build tolerance #5 resistor is null no extra or no reduction of fuel, in a 100% factory fresh IP with no wear potentially a #9 gives 4 cubic mm more/1000 strokes of fuel on top of requested delivery.

In actuality no IP is fresh or built to upper end of tolerances when new so net gain may be more or less than 4mm."


On Edit: Sorry about the formatting... I make it look like a table, and it pops back to unformatted.

[torque454]

I thought 79mm was the max for these pumps??

[jifaire]

You can get 92mm out of a 5068 with a good reflash. Maybe 83mm out of a 5521 with reflash.

You're thinking stock values.

I qualified the data table by saying that those %ages were with a hot-shot IP at Wide-open throttle.

Also need to have a clean tank sock and fuel filter, good LP, , etc.

The calibration resistor is designed to get a pump to spec... if an IP is supposed to put out 65mm, and it only puts out 63mm with a #5 resistor, changing the resistor to a #7 puts it to spec. If it put out 66mm with a #5, you could change to a #4 to make it spec.

It's a trim adjustment.

That means what you gain with a #9 resistor depends on what you have now... if you currently have a #7, you won't notice a #9. If you have a #2, then a #9 will be a +7mm change at WOT, which IS noticeable.