Settng up MAP only unit.

[Wayne in NZ]

OK.

So I have got the Threshold point where I want it.
Do the other trimpots still serve the same functions as a non MAP unit?
I am having an issue with getting the system to "progress" nicely.
Start point is 11"HG (-5psi approx) and I want full at +5psi.
It seems to want to be at full flow by atmosphere.

I am using the 0.9mm restrictor, 1 x 0.7mm jet and 1 x 0.8mm jet.

Any suggestions would be appreciated.

Regards

Wayne

[Howerton Engineering]

Are you referring to what the gauge is showing or mapping of the spray?

[Wayne in NZ]

Well A bit of both.
I can get the system to activate the threshold LED and I can get the nozzles to just start delivery.
There is no "B" on the display at this time and no Warning LED.
I can go for a drive and the delivery seems to just ramp to full at the nozzles and bar graph reads all bars even when I trim the SC down to almost fully CCW.
I have no leaks.
I have the WL full CCW and the WH at full CW and the Failsafe set to full CW and the failsafe reset set to full CCW just to stop them operating while I am setting the system up.
Does the system need to be in BOOST for the "B" to light up or should it light up when conditions are met, given that this is set to inject in Vacuum?
Considering that the Map sensor is providing 0-5V over 30Psi and that 2"HG is approx 1Psi then each Psi from -15 to +15 is about 0.1666V. Atmoshere is 2.5V.
Calculating from -15Psi, 0V.
At 11"Hg (threshold) there is (11"Hg/2=-5.5psi. -15+-5.5=-9.5Psi. 9.5x0.1666=) 1.58Volts.
At 5PSI (max) there is (5Psi=-15+20psi. 20x0.1666=) 3.32Volts
If my calculations are correct or at least pretty close then my range of adjustment is only 1.74V from threshold to max delivery.
Could this be part of the problem.
The system is varying but because of the small window of operation it appears to be NOT varying very much if it all.
Sorry about the ramblings but just getting my head around it all.
Do the other trimpots have thier usual adjustment functions?
EG: Does IDC Trim set at 50% still match Threshold value given it is now Volts and not IDC?

I might try and expand the range of operation of and see what effect this has.

I may have to send the unit back to recalibrate the O Volts and span to more suit this car.

Your thoughts?
Thanks

[Howerton Engineering]

This is the way the unit was first setup, with the span only over the positive side of ATM, ensuring it wouldn't spray in vacuum, and giving you much more range to play with.

Unfortunately, it's not really a "calibration", the board needs to have the resistors and other components on the back side re-calculated and swapped to change what you want. Those resistors are very small....

[Wayne in NZ]

I understand what you are saying, but I want vacuum delivery.
What I was meaning was to move my threshold point a little lower and my max a little higher.

EG:
Threshold at 15"Hg/2=-7.5psi. -15+-7.5= -7.5Psi. -7.5psi x .1666= 1.25V
Max at 7psi. 7psi = -15psi + 22psi. 22 x 0.1666 = 3.66V.
This gives me about 2.4V to play with.

I can probably go as low as 20"Hg and as high as 9psi which increases it all a little more
The biggest problem is that i dont make a lot of boost so really no matter how we span the 5Volts the "progression will be quite rapid.
By injecting in vacuum I can at least extend the span a little more.

Do the other trimpots have thier usual adjustment functions?
EG: Does IDC Trim set at 50% still match Threshold value given it is now Volts and not IDC?

[Howerton Engineering]

I'll have to ask Richard how the unit is exactly. I tested the unit before shipping, but can't say I honestly remember the interaction of the pots with the unit. I'll ask him to refer to his notes on the setup.

Trim at noon should be a neutral value, not affecting the injection.

[Wayne in NZ]

A new development this morning.
I removed the INJ jumper and using two jumpers from another old pc board at work made up a cable with a jumper on each core and routed them to an MSD RPM window switch via a relay, as we discussed by email earlier. I have emaild you a pic of this as I cant post pics here.
This has been working fine until today.
Once the system goes through its start up sequence it then begins to deliver fluid at the full rate. I am unable to reduce the rate of flow.
I have removed the "INJ cable" so that there is now effectively no jumper and it still goes to full flow.
If I turn the Threshold trimmer CW a little, from say 7oclock to 9 oclock, it stops. Something appears to have gone haywire I think.
Your thoughts?

[Richard L]

Need to have the controller back. Not sure if if the controller is suffering from too many extermal modification. Some part of the circuitry on circuit broad is not protected from static. Only modify the cable coming out of the RJ connectors.

Richard

[Wayne in NZ]

Thanks for your reply Richard.
I trust you got my email as well.
I will get it on its way to you first thing Monday.

[Wayne in NZ]

Unit sent via courier on Tuesday morning.
I also included the display.
You should hopefully see it at your doorstep by Monday at the latest.
Thanks