A/F Gauge (not worth it?)
 

OK i've heard mixed feelings about A/F gauges, I'm about to install a SAFC and want to know if its a waste of money to get a regualre A/F gauge or if I should Save up for a wide band. Some people say a narrow band helps but not as well while others say its worthless. What does every1 think?

The A/F gauge is good so that you know what is going on with the O2 sensor. If it starts freaking out, you have an idea of where to look.

They are good for monitoring trends, but are not very accurate or reliable for information really.

I dont see much point in shelling out the cash for a wideband when you can take your car to a shop and use one to tune the car.

If you want to monitor engine condition, and cash doesnt matter, I'd reccomend an EGT instead.

Do the best you can with the money available.

When I install the (cheapo) downpipe, I will be watching the AFR gauge.

Unless you are doing closed loop tunning a Narrow band A/F guage is a total waste of time and money! an egt guage is better spent! If you aren't going to be tunning for Closed loop then I would simply save up for a WB02.

The narrow band O2 sensor is merely a guide. It might keep you out of trouble if you start going lean. It reacts fairly quickly, and I say its a good thing to have.

People who say A/F gauges are useless are simply ignorant, because the thought they could be used for tuning, then found out they were very poor at that so they assume that's because they're crap. The reality is that A/F gauges are a useful diagnostic and monitoring tool that can indicate potential problems if you know what you're looking at. In regular driving you'll see patterns forming depending on load, revs, etc. If you see those patterns change (e.g. doesn't go into closed loop or doesn't go quite as rich under load as usual) then you know something is wrong.

http://fc3spro.com/TECH/MODS/EL/GAUGES/afr.htm


-Ted

i just installed one in my car, it does help. sure its not absolutly needed but i like knowing if im gonna blow something up by being too lean. and of course it lets you know whats up with your o2 sensor. it was worth my 47.99!

I would just like to note that I am not ignorant! I know that an EGT doesn't react as quickly, however it does tell you that things aren't right also! concidering that a Narrow band O2 costs 1/4 that of a WBO2 system that is way more accurate and reacts equally as quick! and they can be used everytime you drive assuming your follow instructions of proper use! If you won't ever need or want a WBO2 setup then yes get a A/F Narrow band guage. But most don't!

Narrowband 02 Gauge: $30-$50
Wideband 02 Gauge + Sender: $330-$450

Dont think 1/4 covers it :-p

I'd get an EGT gauge, but they are pricy!

sorry... good Narrow band o2

OK well i don't plan on using it to diagnose problem i just want it for some rough tuning of my safc before i can get to the dyno, will it allow me to at least smooth out the rich and lean spots?

Your comment "a narrow band A/F gauge is a total waste of time and money" is completely wrong, and IMO based on ignorance of how A/F gauges should be used. That is what I was referring to. It wasn't a personal insult or anything...
You've missed my point entirely. Most people who criticise A/F gauges (including you) do so by saying that it's a crap tool for tuning, so it’s useless. That's like saying an oil pressure gauge is crap at measuring oil temp so it must be useless. An A/F gauge is a monitoring tool, not a tuning tool. Anyone interested in monitoring the condition of their engine should get one, and anyone interested in tuning should get a wideband (or go to a dyno). It's not a case of one or the other; they're two different things for two different purposes. The sooner people realise that the better.

oops...

ok enough argueing i don't care if which of you think your right thats not what iwanna know can i rough tune with a narrow band?

What sort of tuning are you doing? Are you leaning the mixtures for more power or are to going richer them because you think you're too lean? The difference between safe and borderline cannot be seen using a narrow-band sensor...

I'm doing the a rough tunning basicly i want to know if i get the gauge and see that a betwwen 5000 and 7000 rpms i'm rich a bit i'll take it down a notch with the safc will that work?

If you're planning on tuning with it, go with the wideband, you will need the accuracy, and for the money, the Greddy Wideband is probably the way to go if you're looking for something on the cheaper end.

Given a choice between a wideband and the EGT, I'd go with the wideband. Where an EGT will shine is tuning ignition timing or warning you if you have a dangerous condition. With the wideband you can montior your A/F ratio and keep it safe, then use your EGT to determine safe levels of ignition timing. Without the A/F it's difficult to know whether or not you need to add fuel or retard ignition timing.

If you have ignition timing control, another smart investment would be a knock level guage (If you have a Power FC, this is one of the signals you can display. I had one on my 180SX, and I watched it like a hawk.), This is a much faster warning than EGT's that there's a knock spike on your timing map, and with the A/F you can determine if you need to bring down the timing or add fuel to bring it back to safe limits. With the knock level and the EGT you can pull timing out of that area of the map, then try again... if you still have a knock spike and the EGT's are kinda high, you can add fuel to see if you can bring it back down.

My suggestion is that if you're planning on doing your own tuning, save up your money and invest in both the EGT and the wideband, it's very worthwhile and it could prevent an expensive whoops. :D Otherwise if you plan to "set and forget" spend the $50 on a few more dyno runs to fine tune your A/F to a safe level.

If you're planning on tuning with it, go with the wideband, you will need the accuracy, and for the money, the Greddy Wideband is probably the way to go if you're looking for something on the cheaper end.

Given a choice between a wideband and the EGT, I'd go with the wideband. Where an EGT will shine is tuning ignition timing or warning you if you have a dangerous condition. With the wideband you can montior your A/F ratio and keep it safe, then use your EGT to determine safe levels of ignition timing. Without the A/F it's difficult to know whether or not you need to add fuel or retard ignition timing.

If you have ignition timing control, another smart investment would be a knock level guage (If you have a Power FC, this is one of the signals you can display. I had one on my 180SX, and I watched it like a hawk.), This is a much faster warning than EGT's that there's a knock spike on your timing map, and with the A/F you can determine if you need to bring down the timing or add fuel to bring it back to safe limits. With the knock level and the EGT you can pull timing out of that area of the map, then try again... if you still have a knock spike and the EGT's are kinda high, you can add fuel to see if you can bring it back down.

My suggestion is that if you're planning on doing your own tuning, save up your money and invest in both the EGT and the wideband, it's very worthwhile and it could prevent an expensive whoops. :D Otherwise if you plan to "set and forget" spend the $50 on a few more dyno runs to fine tune your A/F to a safe level.

ok but if your saying that an egt is good for igniton timing then i don't need that with the safc as it can't adjust ignition curves right? or is there some other bennifit i would get out of it, i'm on a budget here

I've had a wideband from http://wbo2.com/ TechEdge for about two plus years. It's not for the folk on a budget.

If your on a budget.......you don't need even a cheap narrow band 02 sensor. Use you digital mulitmeter tapped into the 02 output on the ECU. It's just (really more) accurate than those off the shelf items (name your favorite brand, I include it). Or better yet, if you want a light show, then make your own. Just go to AutoSpeed online and subscribe and there are/is at least one article on making your own light show.

I just last week bought a Super AFC (APEXI) from RotaryPerformance in Dallas/Irving/Whatever/Garland??? and from my standpoint, I for the life of me don't see how anyone can tune using one of these if he does not have a wideband unless he goes to a shop/dyno/your choice, and do it there. Ain't no way I could do it with a narrow band and have any confidence that it was done even close to right.

Oh, I also have a EGT. Not that costly if you buy one from PEGASUSAUTO.COM. Ran about sixty to seventy bucks. Hey! I'm on a budget. I'd druther use the wideband though. Personal pref or ignorance, your choice.

$60-$70!! Does that include the sending unit? (Follows the link) . . . dead link ;_;

Hmm ok well that won't work i can't afford that. So does any1 think that a narrow band would allow me to tune it at least a little better than stock? I am getting it tuned at a dyno but i'll have the SAFC for over a month before i get to the dyno

I lied. It's about fifty eight for the gauge and another forty four for the probe/harness. And I keep forgetting to order the light for the gauge.

http://www.pegasusautoracing.com/pdfs/036.pdf

Awesome. I serously wouldnt mind setting up with that dual gauge system, one for each rotor :)

I think I'll wait till I have some money though :)

holy shit balls!!!! why the hell is that K&N A/F guage cost so much? and it ain't even wideband!!!!!

i have a Defi' a/f ratio guage. DO NOT get a Defi' a/f guage, they suck.

An EGT will help to tune or provide a warning that something is not right. Basically it helps you to narrow down a problem. If you have timing adjustment and your EGTs run hot... pull timing. Try again... if they're still hot... add fuel.

For what you have right now, a wideband A/F would help the most. An EGT would be another way of checking, since if you run hot, you'd know to add some fuel back. This would be a lot more accurate for tuning purposes than the narrowband A/F.

My recommendation is still to safely tune it on the dyno and then don't play with it until you save up for the right tools for you to do it yourself.

In order of best choice for just Fuel Adjustment (buget wise):
1) Wideband A/F
2) EGT
3) Read voltage off the 02 sensor, but make sure you know the safe values. I don't know them offhand.
4) Narrowband A/F

OK so i guess the majority here are saying a A/F gauge won't help me? And i thought the EGT reacted to slowly? how would i know what RPM was causing higher (lean) temps? and I'm not talking about something here to tune my car to perfection, i'll leave that to the pros, i just want to see if i can get a little more outta my car for than month after the SAFC intall and before the dyno

dude, just forget it. you can't TUNE without a WB. just wait a month, it ain't worth the time to try and tune with an EGT and a factory O2. by the time you figure out what IS going on, you'll already be at the dyno doing more tuning. save yourself the trouble and don't drive hard for that month. i know it's hard, but, you're asking the impossible.

Thank you thats what i was looking for, but why not drive hard? I drive hard now and run low 15s lol, I know what you mean tho. Also how would reading the voltage off the stock O2 do any good it wouldn't hooked up to a good AF. ohh yeah i think i'd still like to put that AF gauge in the car, any other suggestions on gauges I need 3 for a DIN pod that leaves 2 open

A real coolant gauge . . . and vaccum gauge.

The coolant gauge cuz ours are so innacurate they wont warn us of a problem.

A vac gauge so you can see the tendencies of your engine's vac, and if a problem arises there.

Nither costs THAT much.

If you wanna go expensive, get that dual EGT gauge :)

I don't understand you. It's the AF gaube light show that is punk. The meter has meaning. Stoic is .40vdc. If you see something like .80vdc..thats pig rich. If you see .10 its lean. If you see the meter jumping on either side of .40vdc its *in the loop* and being controlled by the ECU.

But even seeing .80vdc or whatever .....it ain't accurate. Narrow band 02 are only accurate around .4vdc. Anything else is a just in the ballpark figure. Read TRENDS.

I opted for a cheap fifteen buck digital meter from RS for a couple of years. At least it could serve a useful purpose in life.

Oooops. My bias is showing.

But AutoSpeed had an article where they used a homebuilt AF meter and homemade Inteceptor to tune a BMW, after they made an adjustment to the airflow meters vane setting. So the narrow band AF meters can be useful if in trained hands.

well, a friend of mine has been telling me for quite some time to read the volts from the O2 to get a better reading becasue the Defi' guage isn't accurate at all. The vdc to afr graph is funny, between .85vdc and .15vdc shows stoich on the guage. and to think, when i had the 850's in, the guage showing rich, which means it must have been .95vdc or something.

and the stock coolant temp guage works fine. at least mine does. mine rises when i drive it hard and stays down when i don't, that makes perfect sense to me that it works.

i'm not sure if a dual EGT guage is really usefull because you can't adjust each rotars fuel delivery or timing independantly. just get the single and put it next to your O2.

totallimmortal - So you said you are buying SAFC? Are you buying the SAFCII? If that is the case you can moniter the voltage of the o2 sensor. Or any sensor for that mater.

So, if that is the one you got. Just save your money on buying a blinky light thing. And use your SAFCII

And that's not a blinkly light thing? ;)

There is no difference in accuracy between a direct voltage reading (whether on a DMM or S-AFC2) and an LED display. They both show exactly the same thing. The only difference is that it's a whole lot easier to read an LED meter at a glance, as opposed to reading numbers.

I have both an EGT and A/F Ratio Guage. With my level of mods and more to come, I am on the verge of buying the FJO Wideband Unit. Both the aformentioned guages served well and whomever - If they know what they are looking for but as always, It's not enough. :D

It depends on your ability to tune.
*I* use just an EGT gauge and readings off the narrow-band O2 sensor, and I have no problem tuning Haltechs.
Just ask my customers. :)
The wide-band does make fuel tuning a little fast, but I don't find them required.
I tune these cars for street use, and yes they do lose 5% of power from not tuning to the edge, but safe is where I like them for street tuning.
If you're tuning race engines and need to run them to the ragged edge for utmost power, then the wide-band is a must.

I just tuned a customer's 20B NA FC, and the AFR's were pretty much dead on up to 6,000RPM.  It wanted a little more fuel at the very top end to finally nail 232hp at the wheel on a 248x DynoJet, but our street tuning was pretty much dead on through an EGT gauge and an Autometer 20LED AFR gauge.

The usefulness of the AFR gauge is highly dependent on the person using it, and what you're trying to accomplish with it.  I use the AFR gauge to tuned highway crusing for lean and for spotting any deadly extreme lean condition under load, and it was will always react faster than the EGT gauge for a sudden lean condition due to inadequate fuel.


-Ted

I prefer assuming everything is ok over using guages. Nothing more reassuring than thinking you are ok and fixing the problem when it happens with alot of duct tape.

Try this:AEM’s Wideband UEGO Controller is also available in a gauge that includes a single-channel analog output with a Bosch O2 sensor in one unit!

http://www.rx7store.net/index.asp?Pa...rodID=814&HS=1

The AEM wideband is only accurate to 11:1 afr's. PLX's wideband is $329 and they make and sell a unit that takes the output of the wideband and makes the Autometer A/F an accurate gauge for an extra $35. www.plxdevices.com check it out.

The gauge seems like more of a bling bling issue to me. Get an EGT gauge.