thoughts on rpm sensor 12v ford

cjhstang · 05-13-2012, 11:34 AM

If the ford idi sensorr is a four pulse per revolution, couldn't a plate be added onto the fuel pump drive gear with two notches and the sensor be adapted into the gear case housing? Would be clean and should look like a factory setup rather than a 250 dollar adapter setup on the dampener? Make sense?
I haven't had a chance to pull the injection pump gear on the idi motor to see what the sensor is receiving pulses from.
Input?

cjhstang · 05-13-2012, 11:37 AM

Wait, the injection pump does a half revolution when the engine completes one correct? So to make the idea work the injection pump gear would then need eight notches, not two.

johnny499 · 05-13-2012, 01:54 PM

The idi gets it's pulse off of the pump gear teeth and i believe the count is 107. The crank turn twice for every pump revolution because the engine is four stroke. Therefore a pickup on the crank needs to have 53.5 teeth to be accurate i just rounded up on mine to keep the count even. I used the idi pickup coil and wiring on mine, works great.

cjhstang · 05-13-2012, 03:03 PM

Ooo got ya. So with the saw blade you used you cut four teeth of right? Was that just so the teeth count would come down to 54. Great idea by the way, and i'm finally almost done trading your 50 page post...very inspiring!

johnny499 · 05-13-2012, 03:54 PM

Actually it was a sixty tooth blade and i took off six teeth to get the count right. So that was every tenth tooth remove.
Originally i was looking at using a sproket but could not find one the right diameter and tooth count, then o thought what else has teeth and is round. Thats when i thought of the saw blade. I think i paid about ten bucks for it new.. Way cheaper than the kits out there.

cjhstang · 05-13-2012, 04:05 PM

Great idea! I wanted to get something on the injection pump gear and put the sender through the housing. I don't actually have room to mount a sensor at the crank cause I don't have the mechanical fan our pulley so the belt runs right at the spot where the sensor should mount. I'll have to see if I can find a blade with more teeth that may for on the pump gear..

Question got ya. Do you still have information on getting the tps calibrated correctly?

johnny499 · 05-14-2012, 11:01 AM

Ah! Got ya. i would pull the timing cover off and count the teeth on the gears and see if you get lucky. The other thing i have seen done is mounting the sensor to read off the flywheel teeth, but i don't remember the application for that. Whatever you come up with it will be creativity time.

I don't recall the procedure for setting the tps, i think i found it on PSN forum. i know it was voltage readings at idle and full throttle positions, just don't remember voltages.