zwede

I've been wanting a wideband O2 setup for a long time but didn't want to spend $600. Now a new one is out that is pretty fancy and can be had for a total of $260 (including sensor display and shipping), so I went ahead and got one. I got the DIY kit so I spent a few evenings soldering it all together. Installed it in the car last night and went for a drive today.

It's interesting comparing the new WB setup to the regular narrowband I had before. My EFI system can work with a wideband so I now run closed loop all the time. For safety I set full throttle so that the ECU can only add fuel based on O2 feedback, not subtract.

I found the wideband to add alot to the tuning process. First of all, the WB can run even at room temperature. I can see the exact air/fuel ratio when starting cold, and all through warmup. The NB needed about a minute to get up to temp.

When cruising I can now see what the acceleration enrichment is doing. Blipping the throttle just a bit while driving in 5th shot the AFR to 12:1. I leaned out acc enr to where it stays just about the same.

It also helped me find some fuel map issues where the mixture would go way rich for a short time.

I set the EFI to a target AFR of 15.5:1 during cruise and low load, going to 14.7 at medium load and 12.8 WOT. Tomorrow I'll dial in cold start and warmup better.

It will be interesting to see how lean I can go on target cruise AFR before the engine starts complaining. I read somewhere that max fuel economy is somewhere around 16:1.

The kit is made by TechEdgde. Since the mods frown upon links to non-suporting vendors you'll just have to google for it yourself. :)

427V8

Cool, Maybe with one of those even I can tune a carb...Nah!

WA 2 FST

Markus,

Great write-up! It is great that these things are getting less and less expensive. The wide-band sensor/meter I had in my old Mustang was big $$, but that was back before these things were even popular at local dyno shops...and I wasn't going to take chances with a forced-induction engine.

I found on that car that I could get the A/F ratio just a hair over 16:1 at cruise before it would start bucking a bit due to an overly lean condition. Like you, though, I had a user-friendly engine management system that made part-throttle tuning a breeze. Does your EFI allow you to tune on the fly, or do you have to turn off the ignition and reprogram it? Mine allowed real-time changes to be made on the fly which may have not been the safest :lol:, but sure made it easy.

Good luck and keep us informed as to how it goes!

I'm still amazed at the cost. The Bosch WB sensors used to cost $250-300 alone!

zwede

Wes, Yes, the older NTK L1H1 is big bucks now. NTK made a deal with Honda to only supply Honda. The stock is drying up everywhere now and if you can even find it you pay over $200. The techedge uses the newer Bosch LSU4 which was OEM on several cars including some VW's. There's an online VW dealer that sells them for $29.

The Commander 950 I'm running allows tuning on the fly. Very handy.

Brettmc

That's dayum sweet!! Does the 950 require a laptop?

Brett :thumbs:

cardo0

Thanks for the post. :cool:

zwede

Yes, you need a laptop, but only for tuning. BTW, the wideband controller also hooks up to a laptop and can be calibrated as well as reprogrammed from the laptop. TechEdge is working on getting thermocouplers to hook upto the wideband controller for logging. Hmmmmm.... Thermocouplers... Nah, I better stop while I'm ahead.

74-Roadster

Very cool and a good write up. One of these days I need to see your car. :thumbs:

Any chance you'll be at Wichita Falls Corvette Roundup? Or the Good Guys hot Rod show?

Fevre

Thanks for the info Marcus, I have debating on whether to use a stock GM system but the commander 950 is my preference, sounds like the w/b sensor and 950 will be the way I go.

:thumbs:

Cookwithvette

Just a heads up, there are two versions of the Commander 950: base and race. Race version supports w/bO2 sensors and has the O2 target voltage option. Base (what I have) supports neither as far as I know.

zwede

That is correct. Only difference is the firmware, though. You can take a base box, buy a voucher and send it off to holley to be upgraded. AFAIK there are NO hardware differences.

Once the full calibration SW for the wideband is out I think you could tweak it to where it would work without the race option. The wideband has a simulated NB output (0-1V with 1V being rich). You could use this output for the C950 and then enter a custom calibration for the wideband so that when the C950 looks for its hardcoded 0.45V you could really be at whatever AFR you want. Neat, huh? Only limitation is that you could only pick one AFR for the entire map, so you would still have to go open loop at WOT. BUT: You could log your custom NBSim input in the C950 and tune for WOT that way.