AFR at idle

Post by **Cyberkreig** » Sun Sep 12, 2004 9:41 am

I just got my car started, YAY. Lets hear it for the cam angle sensor wires!

Anyway, I installed a wideband o2. its showing 12:1 afr at idle. and it goes even fruther than that if i rev it.. all the way to 14:1.. What is an idea afr for idle and no load revs?

Post by **robbbby** » Sun Sep 12, 2004 3:05 pm

I'd say somewhere between 14-16.

Post by **Cyberkreig** » Sun Sep 12, 2004 3:13 pm

Thank you, I'm new to the wideband and such lean readings had me worried.

Post by **Silvia007** » Sun Sep 12, 2004 6:26 pm

12:1 I think that's rich. 12 parts of air to 1 part of gas where as the ideal afr is 14:1 so the lower the first number the richer you are running. If you start going over 14 then you're starting to run lean. If you rev it, under load or no load and the afr goes from 12:1 to say 10:1 then that means you're running rich.

Post by **Nismo_Freak** » Sun Sep 12, 2004 11:24 pm

12:1 is rich but nothing to be alarmed about... check your fuel pressure.

Alot of engines like to be idled rich.

Post by **robbbby** » Mon Sep 13, 2004 1:23 pm

Silvia007 wrote:12:1 I think that's rich. 12 parts of air to 1 part of gas where as the ideal afr is 14:1 so the lower the first number the richer you are running. If you start going over 14 then you're starting to run lean. If you rev it, under load or no load and the afr goes from 12:1 to say 10:1 then that means you're running rich.

It depends how you are driving your car. When you are idling or just cruising at part throttle the motor will be happy with AFR's over 14. 15:1 or 16:1 isn't out of the norm for part throttle cruising. When you are running wide open you want something probably between 11.5:1 - 12.5:1.

Website · Post by **SoCalS14** » Mon Sep 13, 2004 5:21 pm

What kind of wideband O2 are you running? Where did you get it from?

Post by **Onizuka** » Mon Sep 13, 2004 5:47 pm

He told me PLX wideband on AIM.

Post by **Cyberkreig** » Mon Sep 13, 2004 7:27 pm

thats correct. IT is a PLX m-300 with the digital display. I also got a Stainless bung and had it welded to my new stainless elbow. $20(ripoff) at a local shop.

It replaced my stock sensor, i use its Simulated narrowband output to feed the ECU.

I got it from an online store that is not a nico sponsor, so I wont mention them here. I'll give the url and my impression to anyone that asks off the board.

Website · Post by **SoCalS14** » Mon Sep 13, 2004 7:38 pm

Wow, its a wideband & narrowband deal...cool...How much???

Post by **msaskin** » Tue Sep 14, 2004 7:52 am

Almost every wideband on the market has a narrowband (0-1v) output for running to the stock ECU.

You can get the PLX M-300 direct from PLX, http://www.plxdevices.com, you can also get it from http://www.streetrays.com

Other comparable ones on the market (price-wise) include the Zeitronix ZT-2 (www.zeitronix.com) and the Innovate LM-1 (www.innovatemotorsports.com)

For a bit more money you can get the AEM UEGO's. I run the AEM Gauge UEGO and love it

~matt

Post by **mynismo** » Tue Sep 14, 2004 8:24 am

while we're on topic: anyone know where i can get just the wideband o2 sensor? i already have a greddy a/f gauge but the sensor they gave with it sucks, you have to have it tuned by a dyno shop... what gives...

i heard you can wire up a real wideband o2 to the greddy gauge.

edit: i found the bosch widebands on plx's web site... $59 thats a great price..... any difference between those and the ntk's? (there has to be something behind the much higher price...)

Post by **180crafter** » Tue Sep 14, 2004 8:57 am

I am also currently shopping for a wideband... What do you guys recommend to look for?

Also, the dude with the AEM: does it have narrowband output? How much did you pay for it?

Post by **Cyberkreig** » Tue Sep 14, 2004 9:39 am

I love this setup. Plx makes a converter so that you can hookup their kits to a standard crappy narrowband gauge. Wa-la. Useful!

http://www.plxdevices.com/NB_WB_GaugeConv.htm

Post by **robbbby** » Wed Sep 15, 2004 3:15 pm

Innovate LM1

180crafter wrote:I am also currently shopping for a wideband... What do you guys recommend to look for?

Also, the dude with the AEM: does it have narrowband output? How much did you pay for it?

Post by **Jesse SR20** » Wed Sep 15, 2004 11:05 pm

Silvia007 wrote:12:1 I think that's rich. 12 parts of air to 1 part of gas where as the ideal afr is 14:1 so the lower the first number the richer you are running. If you start going over 14 then you're starting to run lean. If you rev it, under load or no load and the afr goes from 12:1 to say 10:1 then that means you're running rich.

It's my understanding (from reading multiple books) that a A/F ratio of 12:1 is ideal for a turbo application. In fact, dyno tuners aim to achive a 12:1 ratio through the entire rpm band.

14:1 is ideal only for naturally aspirated engines. That would be too lean on a turbo engine.

Post by **compression** » Thu Sep 16, 2004 5:00 am

Some cars run better at different AFR's, you just have to tune your own for best performance and driveability. 11.5-12 is a good ballpark to shoot for whent you are boosting.

Post by **robbbby** » Thu Sep 16, 2004 4:32 pm

14:1 is lean at WOT while boosting. At partial throttle while just driving along it isn't.

Jesse SR20 wrote:It's my understanding (from reading multiple books) that a A/F ratio of 12:1 is ideal for a turbo application. In fact, dyno tuners aim to achive a 12:1 ratio through the entire rpm band.

14:1 is ideal only for naturally aspirated engines. That would be too lean on a turbo engine.

Post by **mynismo** » Thu Sep 16, 2004 6:04 pm

quick question while we're on the subject... does a/f mean anything when your daily driving or just when you are at wot? i want to lean out the car with my safcii at low throttle for daily driving between 1k-3k to get better gas mileage. just don't know how far lean i can go without taking it to a dyno..

Post by **msaskin** » Fri Sep 17, 2004 9:24 am

A/F means something all the time

For best driveability/mileage/performance I generally aim for:

14.7:1 (stoich) at idle.14:1 or so at light throttle cruising. A bit leaner in high vacuum areas, a bit richer in low vacuum areas.13.5:1 at 0 vaccum/onset of boost

smooth, quick transition to richen up as boost hits. Aim for 11.5:1 or so by about half-boost and keep that solid until full boost.

It's a bit conservative, but I'd gladly trade 10hp for motor safety/longevity.

~matt

Post by **lee_harvey** » Wed Sep 22, 2004 12:45 pm

i just bought the cheapy A/F meter (autometer), i was wondering if i got a wideband sensor, could i still use the gauge and would it be reading correctly?

Post by **robbbby** » Wed Sep 22, 2004 3:34 pm

There are certain widebands that can be hooked up to output to a gauge so that the blinking lights are accurate.

Post by **lee_harvey** » Thu Sep 23, 2004 2:56 am

brand/links??

Post by **lee_harvey** » Thu Sep 23, 2004 4:30 am

so,if i buy the wideband sensor and that converter is that all i need?

Post by **ItzGenX** » Thu Sep 23, 2004 7:42 am

Lee, before you totally begin to misunderstand why wideband systems cost so much more then just a little Autometer AFR gauge, I need to point it out so that you don't get the wrong idea. Although many of the wideband systems out have a narrowband output that can feed the stock ecu and narrowband guages and such (like yours), a narrowband system cannot control the wideband sensor. As simple as you think it may be, the wideband sensors need constant regulation and control/monitoring. This is why wideband systems cost much more. The price you pay is for the wideband controller itself. It regulates voltages etc and monitors the sensor keeping regulated power supplied to the sensor. While the sensor doesn't put out an exact voltage for your narrowband gauge to read, the wideband controller converts the voltage to either 0-5v (most widebands), 0-1v (for narrowband feeds), or converts it into a digital display. So in conclusion, you cannot just buy a wideband sensor by itself and expect it to work with your gauge, but instead you need to buy the whole wideband system in order for your low class gauge to read out what the sensor really sees.

Post by **lee_harvey** » Fri Sep 24, 2004 4:54 am

ok, that sounds like something i will do later on then. i still have to get a T3 and bigger injectors. thanks for the info.

Post by **Cyberkreig** » Fri Sep 24, 2004 7:30 am

This is the longest running thread i have ever created. AND it even has useful info. Especialy Msaskins post

Post by **msaskin** » Fri Sep 24, 2004 8:17 am

I guess we'll add some more useful info to this thread. Above I listed quickly some widebands available, so here's a bit more detail. The companies I'm going to list do have more setups available, but below are the ones I've had direct experience with and are all fairly cost effective.

PLX Devices - http://www.plxdevices.comM-300 ($330); 1/2 DIN display, wideband/narrowbard output, no loggingM-250 ($300); NO display, no logging, wideband/narrowband outputM-500 ($500); 1/2 DIN display, logging of up to 4 analog and 2 pulsewidth channels, narrowband/wideband output

Innovate Motorsports - http://www.innovatemotorsports.comLM-1 ($350); can't recall specs, the control box/display is ugly imo

Zeitronix - http://www.zeitronix.comZT-2 ($279-400+); cool LCD display, has hookups for pressure sensor (boost), EGT sensors, etc...

AEM - http://www.aempower.comWideband UEGO ($450ish) - gauge display with LCD for actual A/F and LED bar for quick glances, narrowband/wideband output, can be recalibrated for different output (A/F, Lambda, etc...)UEGO controller ($250-600) - wideband/narrowband output, no display, meant for connecting to a standalone ECU. the more expensive models are two channel, meant for "V" engines running a wideband on each bank.

FWIW, I run an AEM UEGO wideband controller on my car (to go with my EMS).

~matt

AFR at idle

AFR at idle

Re: AFR at idle (Cyberkreig)

Re: (Silvia007)

Re: (Silvia007)

Re: (SoCalS14)

Re: (180crafter)

Re: (Silvia007)

Re: (Jesse SR20)

Re: (Jesse SR20)

Re: (mynismo)

Re: (lee_harvey)

Re: (robbbby)

Re: (lee_harvey)

Re: (Cyberkreig)

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