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I just finished installing a IQ3 dash-only to replace the dash that was part of my G2X in my Miata.

As part of this project, I also added a pair of USMs to take data from my Autometer Elite gauges (they have a 0-5V out to feed a data system), and a bunch of new sensors & data feeds. The G2X was already connected to my ECU (Megasquirt) and supplying 10 channels of data.

The new data feeds to the USMs are:

Autometer Oil Pressure, Oil Temp and Water Pressure gauge outputs
GM coolant temperature sensor at output of radiator (GM 15326386). Sensor and pigtail sourced from http://www.bmotorsports.com.
VDO 0-30psi pressure sensor in coolant system (VDO 360-043). Sourced from http://www.egauges.com/
Fuel Level (piggy-backed off the back of the Miata's dash)
Charge Light from stock dash as trigger (to use as IQ3 warning)
Brake Light trigger

USM/Sensor programming
The GM sensor was configured as a GM degF temp sensor and worked fine.
The VDO sensor was configured as a 10-180 ohm sensor and the 5 data points VDO supplied were used to build a calibration table.
The Miata fuel level feed took some work, and I don't have my notes on what I settled on with me now.

Sensor & Autometer Elite Notes
It wasn't immediately obvious to me, but any 2-wire sensor should be connected to the signal and ground terminals on the USM.

VDO doesn't publish their sensor resistance curves. I had to call them (800-265-1818) and they'd only give me 3 data points. If someone else uses the same sensor, here's the data I was able to get from them:


Also, Autometer doesn't publish a curve for their 0-100psi pressure gauge datalogger output. It's 0.5v=0 psi and 4.5v=100psi. The chart they publish for their temperature gauge seems to cover 60-340 degrees even though some of their temp gauges only go to 260 degrees. The same curve does seem to work for both temp ranges.

Pictures
A couple of shots of the IQ3 and the Autometer water temp gauge:



The other gauges:


Roughed-in USM install:




IQ3 Buttons:


Thanks to everyone at Racepak that helped me get this going!

-jeff

Sounds pretty nice!

Quick question. You say you have 10 channels from the Megasquirt, but then you added about 5 more additionals? I thought the G2X can only do 12 additional channels?

I like my G2X but am getting super close to 12 channels but am finding out I'd always like to add more. I want to run an IQ3 dash in the future as well so not sure if I should just step up to an IQ3 logger and sell the G2X.

I actually added 8 channels to the 10 from the EFI interface and the internal channels.

I've was told the limit is 'soft', and that 2 adding USM would not be a problem.

I've not done any track time with the new setup, but it should be ok.

By "soft" you mean it is possible? Just maybe some channels will log at a slower rate I'm guessing??

BTW did you have a G2X display too? I have heard it is possible to run both an IQ3 display at the same time as the G2X display. Meaning you can use the G2X display as an additional two numeric gauge displays remotely mounted.

I was advised that it wasn't necessary to drop the sample rates--it would just work.

I do have the G2X dash. They seem to co-exist fine, though I haven't done any real testing. This is a photo from when I hooked both up to make sure the IQ3 worked:



Next time I'm at the car I'll reconnect the G2X dash and see if I can get some channels to show up both places.

If it was me, I'd run different outputs across the two displays to maximise the information displayed, and I would segregate the data in each so I had a primary display and a secondary, with the critical data in the primary, and the less critical in the secondary. But then I am a gadget tragic, and my old Mk1 brain would probably crash trying to assimilate all that information, closely followed by the car crashing

_________________
IQ3 logger, Haltech E8, USM

Hey Jeffw did you ever hook up both your G2X and IQ3 displays at the same time during an outing?

Reason I ask is I upgraded to an IQ3 logger (just couldn't pass up the deal I was presented), and hooked up my G2X display. Worked fine together in the garage but when I went out to do laps, it didn't work so well.
I know I have the opposite setup than you now, being you have a G2X logger with IQ3 display, rather me having the IQ3 logger with a G2X display but just wanted to run this by you.

Anyway here's my issues.

1)I couldn't get the G2X to display lap times as I crossed start/finish as it did when the G2X logger was being used.
2)Predictive lap timing wouldn't display on the G2X display either.

I had several teething issues with the IQ3 throughout most of the day and being busy concentrating on driving, but I got some of them squared away eventually. After several tries and finally able to set a S/F point correctly, I was able to get lap times and predictive working on one of the pages on the IQ3 . But the G2X display wouldn't display the predictive not sure why even though i had it display lots of other parameters just fine. I even tried to set a S/F point using the G2X buttons but that didn't seem to work. I think the G2X display isn't able to get the lap time data info from the IQ3 or something.

Anyway just thought I'd ask if you had the chance to run the displays together or not or maybe you just decided not to run the G2X display any longer, which I might end up doing. My goal was just to have mph and predictive lap timing on the G2X display mounted higher towards sight level just as I've ran it previously, so I wouldn't need to stare down at the IQ3 too much except to check temps and warnings every so often.

Thanks,
Jack