i am lookin at purchasing an air/fuel ratio gauge. does anyone know the accuracy of these gauges. is it a worthwhile thing to have? ;)

something like the brand of it would be helpful

I'm not talking about the brand. i am asking someone who has owned one (anyone but u). how one of these gauges wieghs up against an exhaust anylizer.

i ask because:

 

a cheap shitty sensor, uncalibrated, with a jaycar kit hanging off it isn't accurate

 

a brand name air fuel meter that comes with its own closed loop sensor is supposed to be alot better

 

a real exhaust gas analyser is going to be more accurate than either, but we're probably talking 0.2 of a ratio or so. and they also make real-time tuning while you're driving difficult

my mate tunes his lpg car with an EGO sensor from an efi rig. A small voltage is made by oxygen ore something. I'd say that most mixture meters would use an EGO sensor too. Either way you can just plug one into a multi-meter on voltage setting. If the mixture is sweet you get 0.5 V, lean under 0.5V, rich over 0.5V. Might be worth a shot, definitely a cheap experiment.

the brand is speco. and what u said actually makes sense!

i was just trying to help ;)

 

most (all?) o2 sensors work on roughly a 0v to 1v range, the problem is getting them fine tuned so they display accurately, as every brand and model of sensor is slightly different

 

for example the jaycar kit works straight out of the box with a certain model of bosch sensor (i think). say you put an ngk sensor on it, the readings are all out of whack until you get a proper exhaust gas analyser and sit and tune the kit into the new sensor

Ive used a a cheap and a autometer A/F guage on the same sensor. there wasnt that much diffrence in readings, but i could have just been lucky, But they are NOT for tuning, these guages are a approx display, you should really use a wideband exhaust gas analyser.

interesting...... i am not really looking to tune my car off the gauge, i use a exhaust gas anylizer to do that. i just want to watch how varying air temps and other uncontrollables affect my tune. my redline is 7500 so if the car were to run lean for any reason, over an amount of time, it could pop. ouch!

chances are if it leans out at 7 grand you probably won't have enough time to react and shut the key off before the damage is done anyway ;)

Do you have an exhaust gas analyser? Can I like, borrow it? Loan for beer?

nah sorry man. i wish. i get my computer tuned by a speed shop. i drive, he plays with the laptop. its only $50 an hour.......way cheeper than a lashing out a few grand for an anylizer.

doug has one

He does? I thought he had a narrowband?

he got an exhaust analyser ages ago ;)