CHEAP Wideband kits!

Update: I ordered an assembled JAW w/ display, and Canada Post takes *forever* to deliver to Texas. :(

It did arrive just before the holiday, and I spent a couple of days putting it into a RadioSnack enclosure box with a fan, a voltage divider, and a 5V regulator to power a future TPS and MAP sensor. Got it all hooked up, and...

My JAW doesn't sense the O2 sensor heat, so it's not working. Me so sad. Me post info on JAW forums, and end up sending JAW back for replacement via UPS.

I'll post another update when the replacement unit arrives. In the meanwhile, I'm swapping out exhaust manifolds to get rid of the flat gasket on the outlet side, and having a bung welded in.
 
Update:
I installed the AEM kit and it works great. turns out my engine was running super rich most of the time 10:1, and super lean the rest of the time 16.5:1. That's not good.

Presently engaged in some rejetting and have gotten it betweem 13.5 and 15:1 almost always. Idle is generally 14.7:1. that's the easy part, though.
 
Well, as soon as I get my car basically running - I am going to have to get one of these...

Except I don't need the display :)
 
My replacement JAW finally arrived, and I finally got it mounted in my enclosure w/ cooling fan (very spiffy!), and I finally hooked it up to the Ranchero just now.

All I've done so far is check the idle settings, and I like it! 8)

A tiny change of the idle mixture screw makes a dramatic change in AFR at idle - like a 1/16th of a turn and the AFR goes from 13:1 to 15:1, and the difference in idle speed and/or vacuum is barely perceptible. I thought my Autolite 1100 was set pretty well for idle speed and mix, but I've gone from 12:1 to right at 14:1 - I can get leaner, but the AFR and idle get unstable, and from what I've read 13.5-14.7 is great.

I'm off to get a burger and see what it does on the road - wheee!
 
I like it. It's very much a DIY-er route to a wideband, even with the pre-assembled version.

Pros:
* Inexpensive. $100 for an assembled JAW + Display, $45 for the sensor via Amazon.com, $20 for various connectors and enclosure bits.
* Accurate and fast-responding. I got the digital readout, and it tracks changes faster than your eye can follow. I amused myself for awhile just pulling out the choke to watch the AFR change.
* Can datalog RPM and 2 additional sensors. (I haven't messed with this yet, but I've got everything but a MAP and TPS sensors already set up)

Cons:
* FOREVER shipping that reminds me of the old "please allow 6-8 weeks" days.
* Digital readout. I want a gauge, cause my old eyes/brain can't keep up with a digital readout and drive at the same time.

All in all, I think it's a good deal, just don't get in a hurry.
 
jahearne":3mdrkexo said:
What do you guys think about one of these?
...
Click to expand...
That was a good price on the ebay unit, but it's gone now. Those are good products, but $350? And wideband O2 is all it does. I seriously looked at every wideband option I could find, and all of the controller-and-gauge options are just too expensive for me, especially considering the limited capabilities of most of them.

I'm working on converting a $12.99 8-18V Voltmeter to read/display the 0-5V AFR output from my JAW. Then I'll have a wideband O2 that isn't all gaudy, but has digital and analog gauge-type displays. And I still won't have much more than $200 in it, if that much.

Once I get done with tuning the Ranchero's carb, then mine is going onto the Buick's Stage1 455, with a junkyard MAP and TPS sensor. I'll be able to datalog not only AFR, but RPM, MAP, and TPS.

Way more capability, and way less cost. The only downside I can see so far is that it's very much a DIY way to go, and the shipping time is sloooooooowwwwwwwwwww.
 
fb71":4fczzdso said:
jamyers":4fczzdso said:
* Digital readout. I want a gauge, cause my old eyes/brain can't keep up with a digital readout and drive at the same time.
Click to expand...

you could always try a meter lke this. Should be fairly simple to wire in ahead of the 7-segment drivers.

http://www.martelmeters.com/products.ph ... tail&id=88
Click to expand...
That looks interesting...while I'm after more of an old-fashioned look (if I decide to mount it permanently in the Buick), that looks like it'd be perfect to mount in the lid of my JAW enclosure box, right below the digital display.

I like how you add external scaling resistors to measure voltages over 1V, and they give you the table so you can figure out which ones to use to scale it to 0-5V.

Thanks! :banana:
 
I'll post some pics of mine and its enclosure box, to give you some ideas. I've already run amok with mine, added a 0-5V panel meter gauge, built a 5V voltage divider for my Buick's MSD box's tach output, as well as a 12-to-5V power source for the upcoming MAP and TPS sensors (again, for the Buick), and a couple of input protection circuits just to be on the safe side.

Now I need a bigger box to fit it all in, along with some sort of nifty connectors for all those wires. :roll:
 
Work firewall won't let me see the pics, but I am glad to hear that you are having fun and success w/ the electronics stuff.

I've got a few panel meters in the parts stash, so I will probably make up a box w/ those, a few input connectors, and a DB9 for datalogging output.

I don't think I really need to have the JAW in the car constantly, so I'll make the box modular and then I will only have to buy the one :)
 
Hmm, to cross-pollinate here...

jaymers on 14point7.com":p1hz0jug said:
jamyers wrote:
I picked up an Eqqus brand basic automotive 8-18V voltmeter yesterday for $12.99 at my local parts store.

Opened it up, measured the resistor (.420K ohms). Multiplied by 5/18th's and I get .116K ohms resistor needed to replace the existing one.

That idea was a bust. What I thought was a resistor was a capacitor (goofy chinese component markings!), and the resistance is made up of the actual copper windings in the gauge innards, with there being 2 sets of windings to get to the non-0 (8V) starting point (see pic). From a short conversation I had with an Equus tech rep, the only way to reduce the resistance would be to completely unwind the outer winding, then remove a percentage of the inner winding, then rewind only a percentage of the outer winding - then check it and very likely do it over and over and over again until you get the right proportions of Coil1, Coil2, and Combined resistance. Ugh.


Here's what I did instead. Went down to the local electronic-supply store and picked up a 0-5V panel meter,

then made up a new face that was numbered from 8-18 instead of 0-5. Glued it to the backside of the metal face, then put it all back together. Ta-dah!


A needle-gauge that indicates from 8 to 18 (AFR) Then I went into JAW Edit and entered my own VOut numbers to get it to indicate to scale.

I plan to set it in the top/face of the JAW enclosure box, right below the digital display. My only issue is that the meter isn't dampened at all, so it jumps a bit more than the AFR's are. But it's easier to see what the AFRs are doing at a glance than trying to read a digital display (at least for this old brain).
Click to expand...

Putting an appropriately sized resistor in PARALLEL w/ the equus gauge would low the resistance to the necessary value.
 
Bort62":1uwb00mj said:
Hmm, to cross-pollinate here...

jaymers on 14point7.com":1uwb00mj said:
jamyers wrote:
I picked up an Eqqus brand basic automotive 8-18V voltmeter yesterday for $12.99 at my local parts store.
...
Click to expand...

Putting an appropriately sized resistor in series w/ the equus gauge would low the resistance to the necessary value.
Click to expand...

I do keep overthinking that one, don't I? Problem is calculating the appropriate size is going to be close-guess then trial-and-error, since there's no clear way to get just the resistance of the windings minus the resistance of the movement.
Or am I doin' it again? :LOL:

Hey, I'm game for anything - one question though... The capacitor on the Equus was a tiny little thing, wires out each end of a cylinder like a resistor, marked "C2" (need a magnifying glass to see that)...and like a moron, I cut it out when I thought it was a resistor rather than unsoldering it.
Any idea how to determine a suitable replacement?
 
As far as the cap, you can measure its value if you have the right tools.

It is probably just a filter cap however, in which case something like .1uF should work fine.

To calculate the right R value, just measure the total resistance across the gauge, use the parallel resistor formula, and back it out.

Or, you can wimp out - get an potentiometer in the 0-1k range, hook it up in parallel with the gauges windings.

Then hook it up to something providing the same voltage your JAW will @ say 10:1, and adjust the POT until the gauge reads 10. Calibrate it @ a few steps.

Then, take it of, measure it - and use that value.
 
OK, I'll snag a cap and go with it.

Now, I've got .512K ohms across the + and - terminals of the gauge, so a resistor added PARALLEL means it would be also across the + and - terminals, yes?

Found this online, it's the "parallel resistor formula" right?
r=(r1*r2)/(r1+r2) where r is the equivalent resistance of 2 resistors r1 & r2
Click to expand...
OK, so:
* To lower the gauge's sensitivity from 18V to 5V, I need to lower the resistance by 5/18, or .27778.
* So I multiply the existing gauge's resistance by .27778, and get .512K X .27778 = .14222K resistance.
* I then plug .512 in as R1 in the above parallel resistance formula, and see what it takes to get R=.14222, which is .1969 (yields R=.14221)

So I need to add .1969K ohms of resistance across the + and - gauge terminals, right?

What about the scaling, as in the original gauge wasn't from 0-18V, and the signal it's going to get is going to be 0-5V - or am I overthinking it again?

I need more coffee. 8)
 
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