Jump to content
HybridZ

Air/Fuel ratio gauge


ratedZ

Recommended Posts

Hey guys, I’m going to be installing my Air/Fuel ratio gauge this weekend and I only have one question. Exactly where should I clamp on a connector on the O2 censor? Should I clamp on to the green wire or should I go up further away from the sensor passed the wire connection to the wiring harness?....or does it even matter. weird.gif Thanks.

Link to comment
Share on other sites

Guest Anonymous

Shouldn't matter as long as the wire you selected from the sensor is 0-1 volts (depending on your mixture, thats the range of voltage of the O2 sensor).

 

Regards,

 

Lone

Link to comment
Share on other sites

There ARE a couple of consumer available widebands out now. Cost is right about a grand. If this is of interest lemme' know and I'll start prowling around in the TurboBuick and ChevyTalk forums to find the information for you. Both of those have pretty decent EFI forums and this is part of what they talk about. Wide band rox for tuning and when I decide on an EFI ECU it's a must for me. I've been told by someopne who went to SEMA that the new AEM ECU will be self tuning using the WB too - you set the desired A/F in the map and it will adjust the base map on the fly. Sweet! We'll see when it comes out if it can do this, if not it CAN datalog the amount of change and to what cell - just like the FAST and DFI GEN7 can.

Link to comment
Share on other sites

Guest Anonymous

I have a non-$1000.00 Nordskog, I havn't installed the 02 sensor yet so I havn't tried it, I know it won't be super accurate, but I think it'll give a ballpark.

 

Price was way cheap, I believe it was like 30.00 or so from summit. There are several others ranging with gauge and sensor for up to 150.00 or so (Edelbrock and a few others offer them).

 

The Nordskog is a 2" round black face digital bar type with 10 led's, so its resolution is obviously .1 volts per led. I have built a above dash pyramid it fits in so it'll sorta hide up there and not look to far out of place with my Autometer ultra-lites.

 

I would have gone with the ultra-lite gauge but it was over 50.00 I believe for the same damn circuitry (they all use the same single chip, about 15.00 to build if your handy, but I didn't want a project box siting on top of my dash, and electronics is not my strong point at all.), I hate getting screwed, so had to decline the expensive (IMHO) Autometer gauge. FWIW.

 

Regards,

 

Lone

 

Ps: If you sensor is very far from the headers you'll want to use a heated three or four wire O2 sensor if the car isn't running one yet.

Link to comment
Share on other sites

If the unit doesn't cost about a grand then it's using an OEM O2 sensor - t that point th ecircuitry is pretty much just a voltage meter. There's a WEB site out there that specializes in making these more sensitive in the ranges where folks would want to tune fo ra few bucks, if anyone is interested I can try to dig it up. I think I might have posted it here way back when.

 

As for the WB models, a grand is actually cheap! The new ones are using a WB OEM O2 from an LEV vehicle, either Honda or one other. It's a VERY durable O2 that is really helping out the EFI community. I actually ran across one of these units for sale today on either ThePartsTrader.com or the Supraforums.com Head over to those two sites and check around in the ForSale section under Supra icon_smile.gif When I ran across it I couldn't recall where I'd seen someone looking for one (sigh).

 

There's a guy in either the TurboBuick forum or the ChevyTalk group that can help you piece one together yourself too but it'll still be about a grand. The DIY EFI group is also building them - price about the same. The sensor is NOT cheap but it's long lasting, prior WB sensors had lifetimes measured in hours and had to be calibrated with special gasses - yuck! They also cost multi thousands of dollars until fairly recently.

 

What sorts of information did you want to know about them? The older style O2s are most sensitive around stoich or 14.7:1 A/F - the new ones read accuratly across a wide range of mixtures. Since peak power is NOT made at 14.7:1 the WB units are preferred. The others can be used but recognize that on either side of 14.7:1 their accuracy drops off VERY fast....

Link to comment
Share on other sites

I have the Haltech meter. It workes very well.

Sure it is just a volt meter but it works very well.

It has (9) I think led's vs 5 as most others have.

Also it has a data out wire for hooking it up to a data logger..

 

Hope this helps.

 

Dave

Link to comment
Share on other sites

Guest Anonymous

i know this is a little off target here but i was curious and wanted to ask. can't you use a EGT gauge to figure out your A/F ratio? granted it wont be precise. but it would let you know when you are running lean right? isn't the leaner you run the hotter you exhaust? and vice versa for over enriched?

 

although i can see why you would want one if you are running the utmost edge in tuning your car but for a ballpark idea wouldn't a EGT work just as well? just had to ask. thanks guys

Link to comment
Share on other sites

Halmeter and all the others cannot make up for the response curve of the stock O2 sensor - one is no better than any other if they use the OEM sensor tuned for stoich14.7:1 All it can do is give you a more accurate reading on a sensor who's response curve is tuned for the most sensitivity at a point where other than max power is made. Better than nothing but not something I'd rely on to keep my motor from melting down.

 

As for the EGT, you'll find problems there too. How do you know what tempt to tune for? If you're sensor position is different than someone else's then their temp readings will be junk for you and vice versa. EGT don't always read hotter as you go lean, they can supposedly run hotter if the car's tuned such that raw fuel is burning in the exhaust too. Some people actually do that intentionally BTW - it's an "anti-lag" strategy. I've actually got a dual sweep EGT on the shelf and will be putting an EGT in the Supra too. I used the dual sweep unit to diagnose a hosed injector once when I found that one side always ran colder than the other on that motor. EGTs aren't completely useless bu tthey work best if you've had your motor tuned, noted the "normal" EGT at that tune, and then watch for deviations IMO. I don't expect to get much out of it in the Supra honestly but it'll be a nice toy icon_rolleyes.gif Seems most pillar mounts come dual for the Supra and I needed to fill the second one. EGT was recommended...

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...