Looking to have myself a rolling dyno, although I've realized an autometer a/f guage is not going to accomplish this... Everyone is speaking of "wide-band" so I assume this is the way to go. Any first hand recommendations?
Also, Where does it go? in place of the stock one or in addition?

My setup:
01' ITR w/22k Miles
CAI
Toda Cam Gears (set at zero)
DC JDm 4-1 header
Carsound CAT with "SMSP special"
V-AFC

Thanks!

 

it is inserted into the tail pipe...

can the dyno put the a/f ratio on the graph?

 

actually the sensor goes in place of the primary 02 sensor
they do have a sensor that goes into the tial pipe,but thats crap imo , doesnt get as accurate of a reading .

 

uh, let me rephrase... By "rolling Dyno" I mean a quality "dyno-like" A/F reading without being strapped to a real dyno.

If it replaces the factory O2 how does that work with my ECU and V-acf?
I assume it provides a more acurate reading to the ECU... but tied to a guage I can see.

 

Let's further clarify. The primary O2 needs to stay in place if this is going to be an on the street wideband. It does howvere need to be before the catalyst in the cat to be accurate. an O2 bung will need to be added most likely or you can run a test pipe and put it in place of a secondary O2 and do an OBD1 conversion or live with the CEL

I will have a wideband O2 setup on my car within the next month. I will give some details once I get it working.

 

It does not replace the stock O2 sensor... it is added on just to sample the exhaust.

It is more acurate.. just very expensive.

some info.
http://www.brownsword.ca/afmeters.html

 

It doesn't.

If you want a wideband in the car you'll have to do one of two things:

1. Run an ECU that supports it, like an AEM EMS.

2. Weld a seperate bung to your exhaust manifold and just use it from the display in your car. It'll only be good for monitoring that way.



[Modified by newt2, 7:53 AM 2/11/2003]

 

Or power FC

 

well see i put it in my primary slot in replacemtn of my primary sensor becuase i have hondata . . . i have a secondary bung in case anyway .
but yea it depends on the set up

 

It depends on what wideband setup you have.

Some of them - techedge 1.5 for example - can send a narrowband signal to your ECU and allow you to read the wideband in your datalogger or wherever. In this case, you would be able to permanently install the 5-wire sensor in place of the 4-wire. Obviously you will go through more sensors like this, but it sounds like what you're after...

 

And why would that be??

 

Doesn't the stock ECU require it for closed loop operation?

 

yeah, but those of you that run kenji/mugen/skunk ecus dont have closed loop in the first place.
and its not like it will have effect on anything but gas mileage

 

I don't have it on my EMS either, well I don't have it turned on anyway.

Thanks for the clarification.

 

So a stock ECU with a VAFC can run without a primary O2 sensor without a CEL that affects performance? And if it is affecting gas mileage would this imply it is running rich?

 

thats right.
it might run rich, but wide open throttle operation doesnt change. just partial
throttle and idle. fyi, you should always tune in open loop or else your tuning
will be screwed up by short and long term fuel trim settings on the ecu.

 

I thought once stoich always stoich...

So my WOT dyno at around 14:1 is not a good thing.

I read this somewhere:

O2 sensors are used in all modern cars for controlling idle and cruise in a closed loop because the best mixture to have for minimizing emissions and obtaining good fuel economy happens to be 14.7:1. If you run at that mixture under heavy load, especially with NOS or boost, you will blow up your engine -- it is far too lean. Maximum power is acheived at about 12.5:1.

...by the way, do the carsound CAT's come with two O2 bungs?


[Modified by oryanh, 3:46 PM 2/11/2003]

 

In closed loop operation the ECU monitors the O2 voltage and adjusts the fuel table (actually it's a trim off of the fuel table, but you get the point) to keep that voltage steady. When you have no O2 sensor it sees max O2 voltage all the time, which it knows isn't right. What it assumes is that you have a bad O2 sensor so it enriches the fuel mixture to a level that is safe no matter what (i.e. it makes it very rich).

eek!

I'm assuming you're NA because you probably wouldn't have a funtional motor right now if you were boosted. Sgt will most likely correct me if I'm wrong, but I believe for an NA car you want to shoot for an AF ratio in the low 13:1 range.

Edit:

They come with no bungs, you'll have to have them put on by a shop.




[Modified by newt2, 1:56 PM 2/11/2003]

 

actually, it doesnt. it just switches to open loop.

 

Sgt can better elaborate what he tunes to but I tuned to 13.4-13.5:1 based on Hondata's suggestion for an NA motor. and I made the most power there as well.

Trey

 

I've only tuned mine and it's forced induction, so I wasn't sure exactly.

Thanks to both you and Sgt for the info.

 

You shoot for where the car makes the most power. Wherever that may be.

 

Steve you seem to be fearless when it comes to running too lean and deatonating. Is this not really a concern when getting close to 14:! even if the car is stil making power? or is it more true that a car will quit making power before it runs that lean?

 

detonating? lol
yeap. it will quit making power after its out of the range it wants to be in.

 

Hmmm......hmmmmm....i guess i'll give that a try