Originally Posted by RxF

63Fairlane500--

Here's my thoughts and opinions on the FIPL, based on what I've experienced and learned. Best wishes.

GENERAL
The very best place to calibrate the FIPL is at a low to mid-throttle setting representative of typical acceleration and road speed cruising. Indeed, Ford does this via the gage block (0.515") and the scanner tool or whatever they use in production. Most of us don't have the scanner tool! The calibration here (mid-throttle) depends upon the accuracy of the gage block thickness AND that the MAXIMUM THROTTLE TRAVEL screw is precisely set (probably a reasonable assumption). A calibration that you could do at say WOT depends also on the MAXIMUM THROTTLE TRAVEL screw AND the resistance profile of the FIPL. The problem with calibrating at WOT is that this operating point is far away from where most of your FIPL operating points are for acceleration and cruising: you'd probably certainly get poor shift conditions. A calibration that you could do at IDLE is SUSCEPTIBLE to whether the Idle Spd Adj Screw has been turned. BUT IDLE is a more attractive place to set the FIPL than at WOT, because the FIPL output generated there is much closer to most operating points (of throttle) where we need the transmission to make a good decision.

I think you have a couple of options where you need to start, since you've got the increased the complexity by unbolting the whole FIPL bracket!

MAKE SURE THIS PART OF YOUR SYSTEM IS OK AND YOUR FIPL IS OK:
*CHECK THE FIPL FIRST WITH AN OHM METER: Is the resistance about 4.5kohms bet. the 2 outside terminals.
*CHECK WITH YOUR FIPL PLUGGED IN and ignition ON (probe where the wires go into the FIPL. That plug comes out...): Is Vref=5V (almost exactly)? Is Vgnd a very small? Ignore the FIPL output for now which is the center terminal.


TAKE ACTION:
1) Mechanically mount the FIPL to the FIPL BRACKET first! Try hard to mechanically CENTER those T-15's in the FIPL holes as you do this. This will provide some lee-way for later.
2) Loosely mount the FIPL / BRACKET ASSY to the pump with the T27's.
**NOW YOU HAVE A CHOICE, gven your equipment.
Choose one as a starting point:
a) GET OUT YOUR GAGE BLOCK YOU MIGHT HAVE JUST MADE: With
no wire harness on the FIPL, adjust the FIPL / BRACKET ASSY while measuring RESISTANCE from the center terminal to the top terminal (gnd) to get ~1900ohms. Gently tighten the screws-- you may be revisiting them!
b) FORGET THE GAGE BLOCK AND USE THE DVOM METHOD WITH THE key ON: Important: UNplug the power to the fast idle solenoid, ...AND be sure your throttle return springs are holding the Throttle Lever with low speed idle screw set against its respective stop. Probe that center PIN on the FIPL and turn your bracket assy to get V=1.250 volts as a good initial point. Tighten the big T27 bracket screws.

Go for a drive-- you might have to iterate. Hopfully, you'll only have to move the FIPL-- not the big bracket.
**NOTE on your drive
-shift timing
-shift harshness/smoothness
-how readily the truck downshifts when you get on it a little.
Use your observations to help you make an iterative decision.
A higher FIPL output voltage will make your truck wind out farther in any gear and it will kick down more easily to a lower gear.

A NOTE ON FIPL ADJUSTMENT RANGE AND SENSITIVITY!!
The width of the FIPL output voltage window at IDLE is not big (just by loosening the litttle t15 FIPL mtg screws.). WINDOW SIZE~200mV. But within this window, you'll achieve an unbelievably different behavior from that transmission. I RECOMMEND YOU START AT 1.250V AND USE A STEP SIZE OF 0.040V (40mV) in your iteration / drives. Don't give up!