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farmboy1989
08-03-2006, 16:04
I have read a little that you can make a fuel controller for a 6.5 which changes the values of the resistor for the pmd but I have heard that these may not work without using the relearn from a scan tool. Does anyone out there have one that can say whether or not these are really affective without a scan tool? Really, what I would like would be able to adjust the fuel on the fly if I was towing or just cruising. Am I just wishing for somthing that is impossible?
More Power
08-03-2006, 16:25
You could begin Here (http://www.thedieselpage.com/t/fsdresistor.htm) to learn more.

Most say it's not a way to get an adjustable fuel control.... ;)

Jim
DmaxMaverick
08-03-2006, 16:25
They work, but won't work for an "on the fly" adjustment. The resistor value is only read if the PCM loses the value, after a specific # of ignition cycles (key-on or warm-up cycles), or if a read is forced via Tech II. Also, the resistor value only effects WOT fuel delivery (maximum fuel ceiling). There would be no advantage to adjusting the value while driving, as it is only read (when it's read) during an ignition cycle.

Your best option would be to install the highest rated resistor that won't set a DTC, and keep your foot out of it until you want additional WOT fuel. Caution should be used with this, as too much fuel at the wrong time will result in excessive EGT's.
farmboy1989
08-03-2006, 18:43
Would the #9 resistor lead to a drop in mpg's in just normal driving?
DmaxMaverick
08-03-2006, 19:49
Would the #9 resistor lead to a drop in mpg's in just normal driving?

Not if you stay away from full throttle. The #9 may set a DTC, if it is too far from the pump's calibration.
JohnC
08-04-2006, 09:40
About 10 years ago I wasted countless hours trying to perfect this concept. Eventally I figured out that the new value wasn't being read by the PCM.

Put a #9 resistor in, do TDC offset learn to load the value, and if you want to "turn it down" put a block of wood under the throttle pedal. Same effect, less money. You can make a bunch of blocks of different thicknesses and number them....

;)
DmaxMaverick
08-04-2006, 10:34
....and if you want to "turn it down" put a block of wood under the throttle pedal. Same effect, less money. You can make a bunch of blocks of different thicknesses and number them....

;)

Now that's funny. I don't care who y'are....

There was a fellow on Ebay several years ago selling a miraculous MPG improver. He claimed it worked on all vehicles, and was 100% effective. Nothing but a block of wood with a nice paint job and a piece of double sided tape, to be placed under the accelerator pedal. He sold a bunch of them for $2 each (S/H was like $10). I wonder if he ever patented that....

....Gitterdunn!
Cowracer
08-04-2006, 11:03
heres the only true "change-on-the-fly" adjustable fuel controller.

http://www.ssdieselsupply.com/images/products/thumb/78--20050206231939.jpg

Tim
farmboy1989
08-04-2006, 15:30
Do they have #7 resistors? I want lots of hp but i dont want to sacrifice mpg's. This is going to be a farm truck so I wont need to lay a 100 ft strip of black marks. Main duty for part of the year will be to and from town, the rest of the time will be pulling a gooseneck flatbed, pulling anhydrous tanks to and from the field, and possibly pulling a cattle trailer to the sale barn.
DmaxMaverick
08-04-2006, 17:19
I'd suggest leaving the original resistor (or whichever you have) in there. The gains are not significant. In most cases, the power increase can only be realized on a dyno, and at the pump. A Diesel engine, when it comes to fuel delivery and power, has a "point of diminished return". There will be a point in your fueling where you can throw more fuel at it, and get no more power. The resistors are supposed to be selected according to the pump calibration, which should already be at or very near to that point.