I was thinking of picking one up, but have heard many conflicting reports regarding its value as a tuning tool.

Can anyone shed light on this?

Was it successful in tuning rich/lean issues?, or is it advisable to go with an EGT gauge?

Go with the EGT. A/F hooks to the rear O2 sensor (after the cat converter), so it's not accurate. You can make it more accurate by welding in your own O2 sensor before the cat. converter.

I have one, but because I don't have EGT, I can't tune my SFAC as aggressive as I'd like.

Most all A/F gauges are designed for a narrowband O2 sensor. Unfortunately, the only narrowband O2 sensor in MY00 cars and up is found after the 2nd cat. By then, the 2 cats have cleaned up the exhaust so much as to make any measurements useless.

Autometer claims you can just subtract a bar off its gauge reading if you hook it to the O2 sensor, but I don't believe it.

Just for kicks, I hooked up my Field SFC to the rear O2 sensor & it just reads garbage.

i have a autometer A/F guage hooked up to the rear o2 sensor. its not completly useless. it gives you a idea how the engine is running. a EGT would give a more accurate reading.

http://www.jumptronix.com

Good for both narrow and wideband. Excellent product.

Steve http://www.forcefed4.com/

Those blinky blinky light AF meters are total garbage. Don't waste your time.

I use a jumptronix (http://www.jumptronix.com/) in my Talon. The gauge is small enough to fit next to the cup holder if you decide you want to cut up your trim.

This meter read the system voltage, plus the voltage off which ever o2 sensor you decide you want to connect to.

From there it is just a matter of measuring voltage which is far more accurate than those stupid blinky blinky AF meters.

It only costs $85 with a billeted aluminum housing (waste O money), I paid about $50 or so, I don't remember the exact cost.

How much is an EGT gauge, and how difficult is it to install?

I just hooked up a Haltech unit www.haltech.com (http://www.haltech.com) it cost a lot more than any Autometer gauge but it is more accurate not as acurate as a EGT gauge but still a good guessmate. I bought the kit with the O2 sensor included for $230 rather expensive but its worth it for my Corrado.

i was wondering how difficult it was to install a EGT guage too.

An EGT gauge from Autometer is under $100, and the probe is about $100 as well. To install, mount the gauge somewhere, hook up its light to the 12V, drill a hole in your headers, weld in the adapter, screw in the probe, and connect the probe to the gauge.

For EGT probes, I recommend you look at Westach. They sell 200F/s Type K thermocouples with 4' braided lead for $40! Don't spend $100+ on an Autometer or Greddy probe.

Steve http://www.forcefed4.com/

SteveS,

I still can't get over you telling me to get the Jumptronix Air/Fuel Ratio gauge. I'd like to buy this for any and all of my future cars. It reads Air/Fuel ratio in voltage (Ex: .032, .091, etc) and it's instant. A plus feature is that a switch is in the back of it to allow you to view the battery voltage. I think it's awesome and it seems very accurate.

[This message has been edited by Kevin Thomas (edited June 01, 2001).]

SteveS claims the Jumptronix is: "Good for both narrow and wideband." However the Jumptronix website FAQ says:
The Jumptronix meter will work on any car equipped with an Oxygen sensor used to measure the air-fuel ratio that outputs 0-1v.So it won't work the the Impreza's front wideband 02 sensor.

Jon ~~ Yeah, that's what the website says, but I received an email from the Jumptronix maker (Alex Anastasiou) letting me know that the A/F gauge does work with wideband sensors. I just think he hasn't updated his page. He stated that he's had multiple customers install his gauge on wideband sensors.

So, uh, yeah, it'll work with wideband. Wideband is 0-5V, right? That's still narrow compared to the 0-??V it reads on battery voltage.

Steve http://www.forcefed4.com/

Anyone have part numbers for the above mentioned EGT gauges??

Now I just need to know what a good second gauge would be for a double pillar mount...

Where can we find information on what voltage the O2 sensor should read?

-Nathan



[This message has been edited by nmyeti (edited June 02, 2001).]

I use an Autometer Phantom A/F and have no idea what my A/F ratios are with it. Just pretty lights in lean/stoich/rich zones. But no idea what the lights correlate to.

I have a few new A/F meters for 5V front O2 sensor in the 2000+ RS and the WRX, but was waiting for the designer to send the install instructions before I market them.

They are similar to the www.dawesdevices.com (http://www.dawesdevices.com) meters, where you have 2 red lights if very lean, 1 red lights when lean, 1 yellow when stoich, 1 green when about 13.2-13.8 A/F ratio (for NA cars), and 2 green when under 12.9 A/F ratio (for turbo cars). I have the exact numbers written down somewhere.

I also have a couple of adapters to allow using a 1V A/F meter with the 5v O2 sensors. I'll post detail and photos of both of these on my site soon, or you can email with inquiries.

They will be about $59.95 for the converter, and $109.95 shipped for the meters.

Before these were available, I paid $62 for a 1V O2 sensor, $50 for the A/F gauge, $10 for the O2 sensor bung, and $40 labor to remove and replace the turbo up-pipe, and
$30 welding into my turbo up-pipe = almost $200. So, mine are a much more cost effective route. Still recommended to run it with an EGT as well.

Larry www.ImprezaRS.com (http://www.ImprezaRS.com) www.SubaruPlanet.com (http://www.SubaruPlanet.com)