I don't know if anyone's interested here, but thought I would post it. I talked to FJO about their wide band O2 sensor kits and they said that Steve Hayes from the Supra site was organizing a group buy. Steve is ready to do the buy on the kit with just a display screen now and FJO should have in 5 wks time another version with data logging to your laptop with rpm, O2 volt.-ratio, and tps volt. for aprox. $700.00 in the group buy. You can check out FJO at http://fjoinc.com/automotive/ and you can contact Steve at e-mail SHayes@Petroferm.com I'm going for the datalogging version myself. I know its not minimal $$$, but it's about the best price I've found on a real wide band O2 sensor. I realize there is a do it yourself kit on diy-efi now- I looked at it, but I'm a FNG at a lot of this, so the FJO is about my best alternative.

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86 406

 

You really haven't kept up with the DIY-WB have you?.
While the first PCB/parts kits GPs are done, you could have saved about $550.
I'd also check deeper then reading advertising literature.
No flaming meant, but spending that much should involve serious investigation, to include alternatives.

 

oops...wrong button

 

Actually, IMHO - that price isn't that bad. In fact, its pretty good considering the prices of other units out there. HOWEVER, IMHO, at this stage of the game it is pointless to buy one of these when you can build your own for about $175

Tim

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TRAXION's 1990 IROC-Z
Best Time = 12.244 @ 112.51mph (1.778 60' / 7.819@88.32mph in the 1/8)
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels.
Gunning for NA 11's with bigger cam, bigger stall, and bigger exhaust.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

[This message has been edited by TRAXION (edited September 26, 2001).]

 

Ugh,
never mind

 

I think TPIS's version is like 600 bucks...but I think I would try Grumpy's design first...

GregF
87 IROC

 

I just got my DIY WB boards in the mail today. It cost $8 for two boards. The sensor is the biggest money drop at about $170. All the parts (pots, caps, diodes, etc) should be less than (probably by a lot) $100. It can't get much easier than insert the correct value resistor at R3 and then solder it. This doesn't have a means of monitoring it and graphing it but for $300 my Snap On dealer is getting me a 2 channel lab scope. Now this may end up at about the price of the wbo2 someone may be offering but I will have a scope that I can use for making money at my job, which I need anyhow. If you don't have the means for something like this I believe there is also a LED monitor
on DIYEFI.org that can be built for next to nothing.

 

i dont want to flame, but is anybody here walking that thin of a tightrope that you have to have such accuracy to keep your engine from throwing chunks of metal at you?

Just kind of currious why the factory o2 accuracy is so inadaquate for seemingly so many people.

Sell me, why do i need a wide band o2, if im not runnin a 200 shot of nos, or something crazy to the point if my a/f ratio is off i could be buying a new engine.

 

Simple answer is you don't need a wbo2. The factory one will do just fine for tuning everything except WOT, which is where it's accuracy is just a guess. But, you are right that if you have high enough o2 volts that you are *probably OK* on fuel and you should then tune by performance. It's as simple as tuning for best performance when it comes to WOT, and not trying to get it to some magical AFR. That being said, to properly tune WOT you need to have confidence in your o2 and a performance measuring tool of some sort. Seat of the pants is just not going to cut it.

 

Unless you read up on something, you can follow the herd all day long. Read up on how temps, back pressure affect an O2 sensor. Then get back with the real data.
You want to consider X voltage as grand, fine. (BTW, use the name Frank Parker at DIY-EFI, and WB, he done the back to back testing on numerous O2s in controlled conditions and data logging). If you want to stop by Lingenfelter's talk to Jason.

I've been reading plugs for about 30 years now, and I'll match notes with anyone. Had the plugs in my GN looking pretty good, and O2s were at a *safe* 800mv.
Made one pass with the WB and it showed, just a tad under 13:1. Well, made a few more passes, and wound up going 6% (computed) richer, and an indicated 11.8 AFR. Plugs look hardly at all different, but the HP is WAY UP. Sure probably would have found the same thing in 6 passes at the strip, but found this in 6 WOT in second gear. Heck of alot less wear and tear.

The DIY-WB ain't a lab devise, just a tuning aid. Gives you a faster idea of where you are, and whats coming out the pipe.

If you want to make full passes, and plug cuts all day fine by me. I did it that way for many years, but this just happens to be a lil easier.

On a stock engine, it takes a big straw to break the camels back, twist the HP level up and the straws get smaller.

 

so my original thinking of... i dont need a wide band o2 unless im really pushing the limits and getting the very last bit of hp out of my engine... is correct.

however, on a slightly modified engine, say around 280 hp. what could you gain at WOT by running a perfected af ratio? hp gain? thoughts/opinions? .3 - .4 in 1/4?

this is very interesting to me, one because both small blocks i own are weak, (307 & 305) and i love thinking of new ways about how could i ever take them to power readings that somebody would awe over for their sizes.

 

What you *can* gain is a matter of how close you are to being right.
If you going to let the ecm command things other then WOT, and your happy at running stoic., then the only place the WB will aid you is WOT.
If you want to go open loop and have full control of the tuning then nothing will beat having a WB.
For the price of $150 for a DIY WB, it seems *silly* not to have one. You'd save that in being able to dial in a lean cruise.

Just couldn't think of a better work then *silly* at the moment.

 

To answer the question of how much does the mixture affect WOT performance or power, I would recommend the Bosch Automotive Handbook. They have graphs that show the effect of A/F ratio on engine torque, as well as fuel consumption and emissions. You will note that in the region of max torque(and power) 12.8:1 A/F, the curve is rather broad, but does drop off both on the lean side and rich side. I would estimate that if you are within 11.8:1 and 13.8:1 AFR, you probably will only be down 5% in power worst case at each extreme. I am building a DIY WBO2, but want to make it clear that you do NOT need one to tune WOT. Tuners across the country have been doing it without WBO2 for years..... some successfully, others not. I personally have a methodology that allows me to get very close to ideal WOT A/R ratios with only using a std ZrO2 narrowband O2 sensor, and a Diacom data logger. There is no perfect way to set or measure A/F ratio. I know my wbO2 meter will have accuracy limitations, but I will use it as a guide. On the other hand, I could spend $5k to $10K on a "lab" grade Horriba meter and approach accuracies of 0.1 AFR, but what would it really get me in the end? There really is no need to be that accurate, heaven knows the factory cals arent that close!! Like alot of the other stuff we spend our money on, its a fun "toy" to play with, that if used properly will help us make more power.

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Dave Zelinka

 

Handbooks and such are for rough guides. Lots of things can affect what AFR you engine runs best at.
Even thou I spent years fooling with the DIY-WB, really didn't think it would help me much. 30+ years of plug reading and I am rather good at it. In 4 passes with the WB saved me HOURS at the strip or making tuning runs. Necessary?, NO. Helpful?, **YES**.