I was actually looking into getting one of these for water temp monitoring. Is this just as effective as say an aftermarket gauge? I don't know how the temperature is received but I'm assuming from the ECU and I'm wondering how it's all wired up.

 

Yes it connects VIA OBD.

 

Okay... connecting oil temp and pressure sensors to the GoodBox analog aux ports...

Pressure is easy. Plenty of transducers output 0-5V.

Temperature is where it gets weird... Pretty much all sensors are going to work on resistance.
So, is a voltage divider the best option for this?

 

Yes, a voltage divider would work if you feed it a 5V reference. Most universal single-wire sensors are grounded through the mounting thread, so it will be the 'bottom' part of the divider.

But what value of resistor you pair the temp sensor with would depend on the resistance the sensor offers through its temperature range. You wouldn't want to end up with full temperature swing only giving a very small voltage swing, as that wouldn't be very useful and have terrible resolution and accuracy.

What temp sensor did you have in mind? Ideally, they will give resistance specifications over temp range. Or, if unknown, you could measure it yourself by doing as others have done and boiling it in a pan of water while measuring with a multimeter.

 

Thanks for confirming what I've been reading.

Before I torture myself learning any more about electronics, I'm going to try using this and a K-type thermocouple and see if I get enough resolution.

The range from 0°C - 130°C is 1.25V - 1.9V. It's not great but it should be serviceable enough. If not, maybe I can learn how to proportionally double the voltage output.

 

I wouldn't use a thermocouple. For a start, that output voltage range is the kind of range I was talking about that will give you poor resolution and accuracy. You'll be lucky if the GOODbox can show that to 1°C increments. It has a 10-bit ADC which only gives you 1024 value increments and you'd be using just over a fifth of that range.

Also, how would you plan to mount the thermocouple? Off-the-shelf temp sensors obviously have a threaded mounting, but thermocouples are just blobs on the end of a wire.

If you're gonna spend $30+ on stuff for a thermocouple ($14 for the AD8495 breakout board and $16 for the K-type thermocouple), why not go for the 'Fluid Temperature Sensor Kit' for $45 from these guys:

Aeroforce Technology Inc | Products - Sensors

You get a proper sensor (in 3/8" or 1/8" NPT) as well as a 5V reference supply. It's what I have on my car (plus one of their oil pressure sensors) with my GOODbox. Works great, no problems at all for many years.

 

I ordered this off of Amazon.

I plan on using it with this:
https://www.rx8performance.com/produ...or-banjo-bolts

I'm not overly concerned with high precision. Mostly I'm looking for a general health indicator.

 

So, are these still available? work for an 09 RX8?

I have an aftermarket audio setup so the factory screen is just blank right now.

 

I don't have the answers to your question but here's the link to the page:
GoodBox Gauge RX8 | GOODbox Gauges

You could ask them.

 

Found it and ordered it. Looks like it should work fine. Hopefully the expandability will help when I swap the motor to keep the dash clean and clear of gauges.

 

Jut put an order in too. Haven't heard back yet, but hopefully there are some in stock.

 

I talked to these guys a month or two ago and said they were not going to make more until they had more people on the list. You guys that ordered, have you received any confirmation that yours is being made? I may want to get one now too if I can.

 

You know, now that you mention it, I haven't. I should get in touch with them...

 

Not a peep and I ordered now almost a week ago.

 

Well if either of you hear that yours is going to ship, let me know.

 

Nooooo!!! We need you to order to get them to do another production run!

 

What did they say? How many orders do they need?

I emailed them before and he "put me on the list" and would email me when he had enough others to make a batch.

 

 

They didn't. No response to e-mail yet.

 

This thread literally answers these questions in the first post?

 

I received an e-mail reply from Mike at 12:31 AM:

I replied asking for an ETA but haven't heard back.

 

I havent even gotten an email and canceled the transaction with paypal. They havent even responded to that.

 

I emailed them about editing the firmware to add cat temperature as output. No response. Soooo... DIY options?

 

I think this is just a guy doing these in the side, so I tried to give him some slack on the communication times, etc. He did email me a few times explaining how he moved and the old batch was lost and it's too expensive to make up more boards without any preorders. Maybe with enough interest here he'll make another batch.

 

Hey guys,

I'm still here and everything mentioned above is correct.

1. We don't have stock (it's been misplaced and I haven't found it yet)
2. In order to build more, I need to reach a minimum order quantity which right now is 50pcs
3. I'm keeping a list of folks who are interested so I can communicate when we get closer to a new batch (or when I find the ones we have)
4. This is not my primary concern; we're now focused on selling our turn key REW swap kits for the 8
5. I'll be slow on email but will respond when I get a chance
6. I'm watching this thread

Thanks!