DIY digital A/F ratio gauge **PICS ADDED**

[rydog]

This thread has some very good info in it. If I am reading right i can get an lc-1 and wire it to a small digital display instead of using a wideband guage?

[Dan95-5.0]

With that one does it require all the resistor work stated in the first link?  or just hook it up and go?

thats the same one that i want to get but in red.

how did it work out for you?

[Dan95-5.0]

check this one out guys. looks great and the price is right too

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270166870566&_trksid=p3907.m32&_trkparms=tab%3DWatching

[Millhouse]

check this one out guys. looks great and the price is right too

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270166870566&_trksid=p3907.m32&_trkparms=tab%3DWatching

There are a couple of reasons that wont work.  First is the lack of a switch to alter the decimal location...but more importantly it's the voltage range.  In this case you would ideally like 0-5v, but both 0-2v and 0-1v will work as well (assuming you can program the widebands output).  0-200mv is far to small of a range to hold any type of accuracy.

[TexasTwins]

would this be better?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=130124087248&ssPageName=MERCOSI_VI_ROSI_PR4_PCN_BIX_Stores&refitem=270166870566&itemcount=4&refwidgetloc=closed_view_item&refwidgettype=osi_widget

[Millhouse]

I don't think so.  First would be due to the 5v input (you need something compatable with 12v).  If you could regulate the voltage to the meter down to 5v it's possible...but I'm unsure if the 0-20v range is compatable.

[iansane]

This seems awesome. I'd much rather have a small LCD display that another round gauge. Anyways, I just picked up an LC1 that I'd love to install in my firebird in place of the stock o2 (simulating a narrow band) as well as datalogging the wideband into a spare pin on the ecm. Can I just split the analog output #2 (that's the WB reading) into two wires? One for the LCD and one for the computer or with that mess with the reading?

[8 SEC SVT]

I have a LM1 for tuning, But after reading these 5 pages got me thinking. I'm by NO means a electronics guy, so this is why I'm asking. IS there any way to be able to have a 2 color backlight so it could change from a green backlight, to a red backlight when the A/F goes out of a certain range? I mean if making a pass at the track or playing around on the street, I just figured if there was a way to make the backlight change color so you could catch it out of the corner of your eye rather then trying to 'watch' the gauge.

Just wondering (Nice info by the way guys)

[cat herder]

Well that was a nice 5 page read with as many plot twists as a whole season of (insert name of current popular network tv show here). Can somebody please post a summary, all the links are dead (Ebay links only 'live' for ~3 months). Without knowing a part name or number to search for most of this stuff is useless!

[fuelie]

I have a LM1 for tuning, But after reading these 5 pages got me thinking. I'm by NO means a electronics guy, so this is why I'm asking. IS there any way to be able to have a 2 color backlight so it could change from a green backlight, to a red backlight when the A/F goes out of a certain range? I mean if making a pass at the track or playing around on the street, I just figured if there was a way to make the backlight change color so you could catch it out of the corner of your eye rather then trying to 'watch' the gauge.

Just wondering (Nice info by the way guys)

This is a great idea, you should be able to do this with a basic circuit that relays on at a certain voltage.   

[65ShelbyClone]

Yeah, it could be done with a simple comparator circuit.

[stangboy86]

wow. good read

[HomeBlown]

Subscribing

[92GreenGT]

I'm glad I found this thread too because I was wanting to add a display to my LM-1 and was looking at getting a fancy gauge.  I actually like having the readout panel in a different spot than the regular gauges. 

http://cgi.ebay.com/20V-50A-DC-GREEN-LED-COMBO-Panel-Battery-Amp-Voltmeter_W0QQitemZ260332752277QQcmdZViewItemQQptZElectrical_Solar_US?hash=item260332752277&_trksid=p3286.c0.m14&_trkparms=72:1205|66:2|65:12|39:1|240:1318|301:1|293:1|294:50

Does that look like a good candidate for this?  How do you hook them up to the LM-1?  Is there a cable or what, I've never even noticed the analog outputs on the LM-1.

[BottleFed70]

So I did just this with my LC1 a little over 2 years ago.

It works great BUT!    The problem I have is that the display does not update itself often enough.   The display that I have only updates itself about 2x per second.  This makes it really hard to judge what your AFR is when the engine is in a transitioning state (such as accererating quickly).   Works great for monitoring AFR at cruise tho.

For anyone considering doing this, my reccomendation is to try and find a display that updates itself a lot faster than 2x a second.   Unfortunately, this means the cheap ebay voltmeter displays are probably out.  This is where an analogue display really shines.

[Lightning Struck]

http://www.beimeter.com/3_5_digit_ua_dc.htm

Another source of DPM's with alot of options.. 

[Slammed_66]

So let me get this strait, if I biuld the display in the original link, I can put a O2 sensor in my carbed truck and read my AF/r. 

[Dan95-5.0]

OK. A lot of dead ebay links in here.

I'm looking for one where i can just plug and play my LC1 into and be able to change decimal placement via switch like Millhouse was using.

Any links?

How is the visibility during the day? i want mine to be placed infront of my cluster either above the steering column or under dash on the gauge cluster.