Finally tuned and running nicely

The Zeitronix has a dedicated TPS wire, which connects to the ECU harness. Same with rpm. Fuel pressure required buying a pressure sensor from Zeitronix, essentially the same as the boost sensor but measuring gauge pressure rather than absolute. That is connected to the User1 input, while the IAT is connected to User2.

Thanks for the (very) quick reply :)

I didn't know I could read that information too. Will have to look into how to get the TPS signal from the ECU into the Zeitronix.
I have the fuel pressure gauge in my engine bay, but I obviously would need another sensor for the Zeitronix as well.

Do you have the Zeitronix LCD-display as well? It seems I would not be able to display all that data as I drive on one display unfortunately.
 
In my NA2, the TPS wire is on ECM D, the lowermost connector on the left of the ECM, and is the Blk/Red wire in the bottom left corner (from the wire side):
ECM_D.png
I just used an x-acto to cut away the insulation over a few mm length of the wire before the connector (without touching the conductors), wrapped the Zeitronix lead around the exposed conductors, and taped it up.

For fuel pressure, I used the 150 psi Gauge Pressure sensor here.

I'm not convinced that fuel pressure needs to be displayed constantly. Right now mine is, because I just changed my fueling setup and wanted to see it for a while. I use a display that I am making myself, in place of the clock. The nice thing about Zeitronix is being able to hook up a laptop when you want to see all the data. I also have one of their black box dataloggers, so at any point I can capture some data and take it back to a computer to look at.
 
In my NA2, the TPS wire is on ECM D, the lowermost connector on the left of the ECM, and is the Blk/Red wire in the bottom left corner (from the wire side):
View attachment 122653
I just used an x-acto to cut away the insulation over a few mm length of the wire before the connector (without touching the conductors), wrapped the Zeitronix lead around the exposed conductors, and taped it up.

For fuel pressure, I used the 150 psi Gauge Pressure sensor here.

I'm not convinced that fuel pressure needs to be displayed constantly. Right now mine is, because I just changed my fueling setup and wanted to see it for a while. I use a display that I am making myself, in place of the clock. The nice thing about Zeitronix is being able to hook up a laptop when you want to see all the data. I also have one of their black box dataloggers, so at any point I can capture some data and take it back to a computer to look at.

You are obviously much more electronics savy than I am :) :)
I can attach a (single??) wire to the OEM ECU connector as you mentioned, but where to lead it into the the Zeitronix box??
FYI, I have the Zeitronix box in my armrest box. The LCD is currently attached to the lid of the ashtray, but I am planning on filling up the ashtray space and put it inside. I also have the black datalogger box which at this moment I am using every trip to get some datalogs for future reference.

BTW, nice to see someone else is using the ZT box. I bought it to monitor my AFR's but unfortunately, my engine still suffered from detonation, probably from running much to lean at high RPM's at the track. Since then I put it a Walbro, bigger injectors and the additional AIT and boost sensors just in case.
But I am still being careful. The more I learn about the way an ICE engine works in regards to fuel/air-mixtures, (intake) temperatures and ignition timing, the more I seems to think how easy things can go wrong.
 
I can attach a (single??) wire to the OEM ECU connector as you mentioned, but where to lead it into the the Zeitronix box??

Sorry, I should have include that. TPS is the gray wire on the standard ZT-2 harness, also known as pin 10.
ZT-2_pins.png
[TABLE="width: 1"]
<tbody>[TR]
[TD] pin
[/TD]
[TD] color
[/TD]
[TD] Signal
[/TD]
[/TR]
[TR]
[TD] 1
[/TD]
[TD] Red
[/TD]
[TD] PWR in
[/TD]
[/TR]
[TR]
[TD] 2
[/TD]
[TD] White
[/TD]
[TD] Wideband out
[/TD]
[/TR]
[TR]
[TD] 3
[/TD]
[TD] Green
[/TD]
[TD] RPM in
[/TD]
[/TR]
[TR]
[TD] 4
[/TD]
[TD] Orange
[/TD]
[TD] Boost sensor IN
[/TD]
[/TR]
[TR]
[TD] 5
[/TD]
[TD] Wht/Blue
[/TD]
[TD] Warning out (5V 0.002A)
[/TD]
[/TR]
[TR]
[TD] 6
[/TD]
[TD] Yellow
[/TD]
[TD] Boost sensor +5V
[/TD]
[/TR]
[TR]
[TD] 7
[/TD]
[TD] Black
[/TD]
[TD] Pwr GND
[/TD]
[/TR]
[TR]
[TD] 8
[/TD]
[TD] Wht/Brown
[/TD]
[TD] User 2 IN (0-5V)
[/TD]
[/TR]
[TR]
[TD] 9
[/TD]
[TD] Purple
[/TD]
[TD] Simulated narrowband out
[/TD]
[/TR]
[TR]
[TD] 10
[/TD]
[TD] Grey
[/TD]
[TD] TPS
[/TD]
[/TR]
[TR]
[TD] 11
[/TD]
[TD] Brown
[/TD]
[TD] Boost sensor GND
[/TD]
[/TR]
[TR]
[TD] 12
[/TD]
[TD] Blue
[/TD]
[TD] User 1 IN (0-5 V)
[/TD]
[/TR]
</tbody>[/TABLE]


nice to see someone else is using the ZT box.

Yes I love it and have [MENTION=4799]DDozier[/MENTION] and [MENTION=20915]RYU[/MENTION] to thank.

The more I learn about the way an ICE engine works in regards to fuel/air-mixtures, (intake) temperatures and ignition timing, the more I seems to think how easy things can go wrong.

I couldn't agree more. I'm actually fairly surprised that the standard Comptech fueling works for so many people.
 
Sorry, I should have include that. TPS is the gray wire on the standard ZT-2 harness, also known as pin 10.
View attachment 122654
[TABLE="width: 1"]
<tbody>[TR]
[TD] pin
[/TD]
[TD] color
[/TD]
[TD] Signal
[/TD]
[/TR]
[TR]
[TD] 1
[/TD]
[TD] Red
[/TD]
[TD] PWR in
[/TD]
[/TR]
[TR]
[TD] 2
[/TD]
[TD] White
[/TD]
[TD] Wideband out
[/TD]
[/TR]
[TR]
[TD] 3
[/TD]
[TD] Green
[/TD]
[TD] RPM in
[/TD]
[/TR]
[TR]
[TD] 4
[/TD]
[TD] Orange
[/TD]
[TD] Boost sensor IN
[/TD]
[/TR]
[TR]
[TD] 5
[/TD]
[TD] Wht/Blue
[/TD]
[TD] Warning out (5V 0.002A)
[/TD]
[/TR]
[TR]
[TD] 6
[/TD]
[TD] Yellow
[/TD]
[TD] Boost sensor +5V
[/TD]
[/TR]
[TR]
[TD] 7
[/TD]
[TD] Black
[/TD]
[TD] Pwr GND
[/TD]
[/TR]
[TR]
[TD] 8
[/TD]
[TD] Wht/Brown
[/TD]
[TD] User 2 IN (0-5V)
[/TD]
[/TR]
[TR]
[TD] 9
[/TD]
[TD] Purple
[/TD]
[TD] Simulated narrowband out
[/TD]
[/TR]
[TR]
[TD] 10
[/TD]
[TD] Grey
[/TD]
[TD] TPS
[/TD]
[/TR]
[TR]
[TD] 11
[/TD]
[TD] Brown
[/TD]
[TD] Boost sensor GND
[/TD]
[/TR]
[TR]
[TD] 12
[/TD]
[TD] Blue
[/TD]
[TD] User 1 IN (0-5 V)
[/TD]
[/TR]
</tbody>[/TABLE]


Yes I love it and have [MENTION=4799]DDozier[/MENTION] and [MENTION=20915]RYU[/MENTION] to thank.

Thanks for the detailed information.
Did you just take a single strand wire from the ECU and just braid it into the Zeitronix harness then??
Shouldn't be too far, since the ECU and the armrest box are only about two feet apart.

I couldn't agree more. I'm actually fairly surprised that the standard Comptech fueling works for so many people.

Well, as for me, the reason it worked so well was the reason I decided to take the plunge. Wish I had known more about it then, even though I did choose to include Zeitronix at the time. With normal street driving, most people don't stay in boost for very long and the Comptech box seems to work quite well.
In my case, probably all the high-rpm track sessions ruined my engine (after about 8K miles). After replacing the engine, I found that it would run lean above 6500 rpm, even with the Walbro. And also, the ignition timing wasn't retarded enough according to the tuner I contacted.
So that's when I got the 550CC injectors and the AEM F/IC controller.
But I am still looking for potential problem points.
At the moment, it seems that sometimes, the ECU doesn't respond quickly enough when I apply just a bit of throttle when cruising.
Sometimes, when I am doing 50 mph on the highway (for example) and apply a little throttle (not even going into boost most of the time), I see my AFR going up to 15-16.5 for a second before it comes down again.
That's why I am currently logging all the data and would like to have the TPS input as well.
One problem is (not really a problem actually) is that as soon as you lift the throttle, the fuel cut-off cuts in, and your AFR on the ZT goes up to 21.0 because the ECU is saving fuel.
 
Did you just take a single strand wire from the ECU and just braid it into the Zeitronix harness then?? Shouldn't be too far, since the ECU and the armrest box are only about two feet apart.

I added the Zeitronix before I had the piggyback; if I had the piggyback first, I would have done this to the wires of the piggyback harness, but the idea is the same:
wire_tap.png
Then wrap it tightly with electrical tape. The wire to the Zeitronix could be your own wire that you then connect to the gray Zeitronix wire. Use stranded wire; the gauge probably doesn't matter since very little current flows through it (i.e., 24-22 ga is fine). My ZT-2 is next to the ECM, along with the boost sensor and the piggyback. It's a bit crowded in there but it went together fine.

At the moment, it seems that sometimes, the ECU doesn't respond quickly enough when I apply just a bit of throttle when cruising. Sometimes, when I am doing 50 mph on the highway (for example) and apply a little throttle (not even going into boost most of the time), I see my AFR going up to 15-16.5 for a second before it comes down again.

You should look into the tip-in enrichment of the FIC. It's available in the current version of the software. Mine is currently a bit too aggressive and the AFR drops too much with getting on the throttle. I can get the settings that I am using for you later. To see if it helps, my tuner suggested starting with limit of 20%, sensitivity of 25%, and fuel of 10%. I believe he added to that during our driving session after the dyno, but I haven't pulled the settings to see where it ended up.

- - - Updated - - -

Of course, the tip-in enrichment of the FIC requires TPS to be connected. So once you connect it, that may be a big benefit. Here's how AEM describes the parameters:

These settings are used to emulate an acceleration enrichment pump. Sensitivity will determine how fast or slow conditions must change in order to activate the acceleration enrichment pump. Fuel percentage will set how much fuel will be added to whatever area of the map the abrupt increase in load is applied to. Limit percentage is the maximum amount of fuel increase you want to allow for. Duration in ms is the amount of time the pump will be activated for when the F/IC senses an abrupt change in throttle position.
 
Last edited:
I added the Zeitronix before I had the piggyback; if I had the piggyback first, I would have done this to the wires of the piggyback harness, but the idea is the same:
View attachment 122655
Then wrap it tightly with electrical tape. The wire to the Zeitronix could be your own wire that you then connect to the gray Zeitronix wire. Use stranded wire; the gauge probably doesn't matter since very little current flows through it (i.e., 24-22 ga is fine). My ZT-2 is next to the ECM, along with the boost sensor and the piggyback. It's a bit crowded in there but it went together fine.

You should look into the tip-in enrichment of the FIC. It's available in the current version of the software. Mine is currently a bit too aggressive and the AFR drops too much with getting on the throttle. I can get the settings that I am using for you later. To see if it helps, my tuner suggested starting with limit of 20%, sensitivity of 25%, and fuel of 10%. I believe he added to that during our driving session after the dyno, but I haven't pulled the settings to see where it ended up.

- - - Updated - - -

Of course, the tip-in enrichment of the FIC requires TPS to be connected. So once you connect it, that may be a big benefit. Here's how AEM describes the parameters:

Again, thanks very much for the info.
My tuner did the work in my absence. I do remember he had trouble with inputting the numbers he wanted (decimals), but finally managed to solve it.
I planned to contact him anyway, as soon as I have enough logs from the Zeitronix to explain my problem.
It is one of the reasons I am still carful about going to WOT, although when I do that, my AFR jumps down to 11-11.5 immediately.
So, full throttle looks ok, it is the partial throttle that seems to be reacting slowly. I just hope it doesn't kill the engine.
 
It could be that your fuel map just need enrichment at loads below WOT. But I would definitely get TPS connected; I realize now that it is likely connected to the FIC already, so you can use tip-in enrichment. Just connect it to the ZT-2 for better logging.

Also, connect the wideband output of the ZT-2 to the corresponding input on the FIC, so your FIC logs show AFR. It's pin 18 on the 22P connector, Aux in.
 
It could be that your fuel map just need enrichment at loads below WOT. But I would definitely get TPS connected; I realize now that it is likely connected to the FIC already, so you can use tip-in enrichment. Just connect it to the ZT-2 for better logging.

Also, connect the wideband output of the ZT-2 to the corresponding input on the FIC, so your FIC logs show AFR. It's pin 18 on the 22P connector, Aux in.

At WOT, my AFR seems to be fine, so I think you are right. It's just those small daps at the throttle that the engine lags a bit (and even then not always).
Thanks for the idea. I don't think my tuner considered hooking anything from the FIC up to the Zeitronix. And I didn't know the F/IC logs anything.
But you idea is great, thanks. I am going to contact the tuner who installed the F/IC for me. He should know how the wiring runs.
 
The FIC has a small internal log memory and will log everything if connected to a laptop.

Did you use a premade wiring harness? The SOS harness only has one wire spare, an orange one for AFR input. I bought the appropriate contacts so that I could add other connections to the FIC, like its analog in/out and 12V out. These are the contacts: Molex Micro-Fit 3.0 receptacles.
 
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I bought the F/IC from SOS with their wiring harness.
I think it shouldn't matter if I take the TPS signal from either the ECU or the F/IC connector. In both cases it should be the same.
For the Zeitronix, I had an extra AFR sensor installed in the front exhaust bank, but the ECU uses the original OEM ones.
 
I found it frustrating that SOS didn't seem interested in helping with a pin diagram and didn't include a number of wires in their harness. But extra pins are cheap once you figure out what they are.

I agree you could take the TPS tap from the factory harness or the piggyback harness. I suggested the piggyback harness just to minimize irreversible changes to the car.
 
You need one of these:

IMG_1942.jpg


IMG_1940.jpg


IMG_1939.jpg


IMG_19451.jpg


Dave


Dave,

you need to get a group buy going, i'm sure you could find atleast 5 buyers, me being one as i just received my ctsc last week!
 
My plate is quite full at the moment, if someone wanted to take lead on the group buy project I would be happy to cut as many as are needed as long as we have 10 buyers, but for the little amount of profit in a part like this I would not be able to justify spending any more time on the project other then making the parts and shipping them to a single person that would then distribute them to the group participants.

Dave
 
It's part of the original CT casting. With the spacer I can leave material there and soften that ledge but with or without there will be little difference in flow due to all the turbulence from the blower discharge. My concern with the ledge is a possibility of coolant pooling on the ledge but that is not likely either as it will only spray when in boost. The correct way to fix that part would be to machine the intake to the correct opening in the first place.

There was little work put into the original intake design as far as flow goes it was all about making it fit under the engine cover. The later designed kits have the upper part of the intake bolted in place and the opening is a little better matched to the blower outlet.

Dave
 
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