Are A/F gauges a crock?
+ Reply to Thread
Results 1 to 9 of 9

This is a discussion on Are A/F gauges a crock? within the Interior Mods forums, part of the Tech & Modifying & General Repairs category; I've read a lot of posts on Air/Fuel gauges. Some guys praise them and others damn them. So, what's the ...

  1. #1
    MisterX's Avatar
    Join Date
    May 2002
    Location
    Prague, Czech Republic
    Posts
    2,971

    Are A/F gauges a crock?

    I've read a lot of posts on Air/Fuel gauges. Some guys praise them and others damn them.

    So, what's the story? I've got oil pressure and temperature, boost, and, EGT gauges. I've got one more pod to fill and right now, I'm thinkin' about a clock!

    I'm adding sti injectors and a walbro fuel pump. Do I need an A/F gauge?

    misterx

  2. Remove Advertisements
    ClubWRX.net
    Advertisements
     

  3. #2
    Registered User is2scooby's Avatar
    Join Date
    Jun 2002
    Location
    Honolulu, HI
    Posts
    4,234
    I have had an Autometer A/F ratio gauge in a supercharged V8 before and I agree that it's just a "light show" (ala KITT in Knight Rider ).

    There has been talk that the Greddy A/F gauge is more accurate.

    I actually decided not to buy a center gauge pod (which I think is a very elegant solution) because I couldn't think of 3 gauges I'd want to/was willing to run. My list topped out at boost & egt.

    I know the only other thing that I wonder about is oil pressure, but I'm thinking the plumbing on that one might be a bit of a bear on the sending unit of that particular gauge.

    Good luck with your search for a 3rd gauge! :-)
    Aloha, Richard...
    Retired Moderator
    TXS Stage 4 UTEC + TMIC + JoeP
    12.75 @ 105.67mph - 1.74 60'

  4. #3
    MisterX's Avatar
    Join Date
    May 2002
    Location
    Prague, Czech Republic
    Posts
    2,971
    Originally posted by is2scooby
    I have had an Autometer A/F ratio gauge in a supercharged V8 before and I agree that it's just a "light show" (ala KITT in Knight Rider ).

    There has been talk that the Greddy A/F gauge is more accurate.

    I actually decided not to buy a center gauge pod (which I think is a very elegant solution) because I couldn't think of 3 gauges I'd want to/was willing to run. My list topped out at boost & egt.

    I know the only other thing that I wonder about is oil pressure, but I'm thinking the plumbing on that one might be a bit of a bear on the sending unit of that particular gauge.

    Good luck with your search for a 3rd gauge! :-)
    Thanks for you input. IMHO, If you want to run run oil temp and pressure gauges, the most elegent solution, from an engineering standpoint, is the Defi sandwich that fits between the block and the oil filter and offers two 1/8 NTP ports to your oil system.

    So far, all I've heard about A/F gauges is the "light show" thing. Most people say they are annoying.

    misterx

  5. #4
    Registered User
    Join Date
    May 2002
    Location
    Indiana
    Posts
    25
    I have boost, oil pressure, volt, egt, water temp and A/F. I would say that A/F is probably the most useless. That being said it looks pretty sweet front and center on my center gage pod I am putting in an aftermarket stereo so i opted for no clock. I would've gotten a clock instead of the A/F gage if I wasn't planning on the stereo.

    C-

  6. #5
    Registered User
    Join Date
    Nov 2002
    Location
    AZ
    Posts
    21
    does your a/f even look like it is working? The one I have bounces around all the time, essentially doing what it wants. May have to go to a wideband to get any use out of it?

  7. #6
    Moderator aussieinstlouis's Avatar
    Join Date
    Jun 2002
    Location
    S34 47.322 E138 29.131 (WGS84)
    Posts
    2,516
    It is not the gauge that is accurate or otherwise - it depends on what type of O2 sensor you are using. It is also 'only a light show' if you do not understand what the O2 sensor output is and how to interpret that.

    Narrow band O2 sensors do not have a linear output and are no good for tuning, however they are a good 'health check'.

    The Greddy gauge does come with a 'semi wide band' sensor and can also be calibrated for a wideband sensor.

    I use the autometer gauge hooked into the rear O2 sensor - I also have an EGT gauge and find it useful.

    Cheers,

    Andrew

  8. #7
    Registered User
    Join Date
    Jul 2002
    Location
    Milwaukee, WI
    Posts
    72
    actually I just went to get my a/f gauge put in along with my egt gauge. Originally i was planning on hooking the a/f gauge up to the stock rear o2 sensor. however, supposidly in the MY02 wrx the volts of the a/f gauge dont match up with those of the 02 sensor. So basically im buying a new seperate o2 sensor that will give me a more accurate/better reading. If you go this route i think autometer is all gravy

  9. #8
    Registered User cyrilgrey's Avatar
    Join Date
    Nov 2002
    Location
    Queens, NY
    Posts
    2,190
    I was using a digital A/F gauge with a nitrous sytem in my last car. It seemed to be accurate all of the time. At idle and part throttle it was stoich, at full throttle rich, under deccel lean and on nitrous stoich when set up correctly.
    When my cat died it reflected a change, and when the air filter needed cleaning it also reflected that change.

  10. #9
    Registered User MadDog's Avatar
    Join Date
    May 2002
    Location
    Land of many cows
    Posts
    136
    Originally posted by N8DOGG
    however, supposidly in the MY02 wrx the volts of the a/f gauge dont match up with those of the 02 sensor.
    The Front O2 sensor generates different amounts of current, and uses that to guage A/F. So you can't use the readings off of it, or you'll confuse the readings and won't get a normal guage to read it anyway. The rear O2 is just a normal voltage based one. Unfortunately, it's not usefull for tuning because, well, it's after all 3 of the cats. It's really there as a "cat efficency" tester.
    Trunkmonkey Racing
    Team Monkey Wrench

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself. We strongly suggest that you stay away from using aol, yahoo, msn, and hotmail accounts. Sometimes the mail server blocks the emails from our server. As a result you will not receive any notifications including the confirmation email.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •