Maybe, just maybe an end to SD issues?

[WS6FirebirdTA00]

My in-car IAT controller is setup now lol

I found a potentiometer at work that will give me a range from 30-280*F (I am going to wire a resistor in so I can shift the temps lower from about 0* to about 140*F. It has fairly well resolution under about 110*F. Now I will beable to adjust my fueling without having to tune the car every day. I still plan on seeing how bad an SD tune is (if at all) with the IAT reading constant.

At least now I wont have lean startup issues. I just have to find a spot for the pot. because my ash tray is taken up with all kinds of switches. I may redo it if I can find another ash tray, anyone know the p/n?

[MeentSS02]

If you find the p/n, let me know...I need to redo mine as well. I was using it for my LC-1 push-button grounder, but don't need it now with the XD-1 installed.

[99hawk589]

10261420.

[WS6FirebirdTA00]

sweet, what about the TCS button pannel for the T/A? I ended up putting the piece there for now but may want to switch it, I have zero room in my ash tray. I may make a hidden pannel and replace that piece when I get around to it.

I will post pics tomorrow. I just need to find a clean way to label it.

[S2H]

I had some sucess today with setting my bias to a fixed value that was inbetween the ECT and IAT..still biased towards IAT...but it oesnt seem to overcorrect as much..
so its just gotta be as simple as figureing out what the bias really needs to be...
sounds like time for me to come up with a way..LOL

[Synergy]

What about a potentiometer, wire it up in the car to a dial and you can adjsut the air fuel as you drive, no more worries lol

I use this on the dyno, works good.

Rick

[99hawk589]

sweet, what about the TCS button pannel for the T/A? I ended up putting the piece there for now but may want to switch it, I have zero room in my ash tray. I may make a hidden pannel and replace that piece when I get around to it.

I will post pics tomorrow. I just need to find a clean way to label it.

10280510.

[EC_Tune]

How about the filter funtion? Anyone adjusted that?

EC

[WS6FirebirdTA00]

well, there is hardly any resolution for hotter IAT's, so maybe that is the issue? The computer is trying to read a large range of temps but having a hard time doing it. From 0-2000 kohms it goes from 280* to 100* and from 2000-4000 is only a 308 spread.

Only problem is the bias factor doesnt work on old OS's

[S2H]

How about the filter funtion? Anyone adjusted that?

EC

last night I did a log of bias at 0 and bias at .500
and saw a huge difference....
so I'm working on figuring out where in between it needs to be...

I just got home..slept..woke back up and am just typing responses before heading off to work..so I'll try to post some results later...

the bias filter doesnt seem to be really all that drastic of a difference between airflows so I dont think thats too big of an issue...and I've tried it higher and lower....really dosnt seem to help much either way on teh bias filter...
the bias on teh other hand makes a huge difference..and I'll post that when I get a chance

[S2H]

here real quick are teh 2 logs I did..one right after another basically..

do some filtering and look at when IAT and ECT are simlar
in each file and you will see how much difference the bias factor makes...

in mine I set up to log the bias filter table..(0,10,20,30,40,50,60,70..etc..dynamic airflow)
and plotted AFR error

you can see where down low it made more difference than up higher...

[WS6FirebirdTA00]

I would try it out but its too much of a PITA driving my car with the 2002 OS in there, it always want to dip down to low rpms and transient fueling is odd, my car didnt like it. I wish this worked on the 2000 OS.

[WS6FirebirdTA00]

Well, it worked pretty well. I am quite suprised at how much the AFR changes with little changes in IAT. I will try to post a log in a little to just show some of the things. Next step it to tune the car when its cooler, around 60*, and that will put me in a better range I think for adjustability.

[S2H]

I did a test this morning to see how bad the IAT really is...
it moves way too slow....
I checked it hot with known temperature using a digital thermometer from my dads work that reads instant....
went from hot..to cold.....and watched how SLOW it changed....
so its partly the fault of poor engineering on the IAT..
perhaps somebody else makes an IAT that moves a little faster....and responds to heat changes a little more real time...possibly a later years IAT or some other vehicle all together ike a honda or something..LOL

I also noticed that I could change the AFR some at idle with spark(Idle was my controlled environment with steady ECT for AFR testing)


looking at teh spark adders it looks like the upper side of airflow has some spark pulled out for hotter temps..so I did teh same at idle and low and behold I got some changes in AFR that stayed more consistent as IAT went up...

its still not quite enough..but now I'm gonna work on a spark vs IAT table that will suit it better..
and try it on a cammed car to make sure I dont ruin idle too much.LOL

[WS6FirebirdTA00]

so what are you saying? higher timing is leaner?

[S2H]

yes..Higher IAT was leaner with nothing else being changed...
removed some spark at high temps and it got richer...

looking at the adder tables it looks liek there is a bunch of spark taken away at higher airflow and higher IAT...so taking out spark also richened up the misture....

so my next step it to try to figure out where the spark removal needs to begin...and what it needs when AT is cold to get it back to the correct amount as well..

[MeentSS02]

Wow...my head hurts.

[WS6FirebirdTA00]

It woudl be a lot easier with an IAT VE multiplier vs load lol. I am going to take some pics of what I did with teh pot, I need to make a nice looking label or find a better spot for it.

[WS6FirebirdTA00]

Here it is. Like I said I want to make a better label, once that is a better circle lol. I also plan to cover the entire pontiac logo. In the yellow circle, you can see where I ran the wires to the inside of the car.

I also put in a 500 ohm resistor so now my range is 28*F to 154*F. I will try to find my usb stick and show what I did on start up. I have to tell the computer the IAT is around 60*F on start up to get a 14.7 AFR. There have to be some other calculations going on saying if the car sits for xx amount of time, the air will be hotter, pull fuel.

[ninobrn99]

so is this a much more advanced version of the old IAT free mod? im trying to stay with you guys here, but im losing ya..quick