WTB: CO meter

[Guest Anonymous]

looking to buy a CO meter to tune my fuel/inj set-up. anyone know where's a good place to get one at a reasonable price? or anyone have one they are looking to sell?

thanks,

tim

[Guest Anonymous]

A Bosch single sensor at $30 will do the job along the Air/Fuel Ratio gauge.

[Guest Anonymous]

A narrow band O2 sensor (one, three and four wire variants) was engineered to keep modern cars at stoch (AFR=14.7). There is a huge voltage change around 14.7 (it goes from about 0.9V to 0.2V).

You don't need an AFR gauge, a common multimeter will work just fine.

If you use a one-wire sensor, you need to put it into the exhaust system so that it gets sufficiently hot (I think the threshold is 600 o). If you want to stuff it up the tailpipe, you need a four wire sensor. Two wires heat the sensor to operating temperature, and the other two wires provide the signal and return.

If you want to do any fancy tuning, you'll need a wide-band O2 sensor. Quite a different creature and a different story.

Cheers!

John N

[Guest Anonymous]

any place i can go to lay my hands on info that outlines how to use the two to measure CO%?

sounds to me like i should get a four wire O2 meter - any suggestions on best place and resonable price for an O2 meter.

thanks for all the help.

tim

[Guest Anonymous]

It measures O2.

I will claim to know nothing about the black art of K-fish adjustments. There is certainly a relationship between the ratio of O2 / CO2 / CO and the rich-lean condition of the mixture.

Cheers!

John N

[Guest Anonymous]

I mean uwelding a nut on the headers and screwing the sensor in place. Anyway, tuning a motor is a continuous process that never ends...

I have programable injection and a narrow band Bosh 1 wire sensor. I never really needed to know what happened if I were super rich or super lean, the car would tell me itself by bucking. The narrow band around which the sensor is efficient is, in my case, more that enough to tune the car. Of course it is tuned for power, which means that I do not care about being stochiometric. I am always a bit on the richer side of it. Except at idle where I tuned it lean...

[Guest Anonymous]

If you take the downpipe off, there is room to weld a bung on the outside (nearest the inner fender) and put the sensor there. Out of the way and relatively easy to run a wire to it. I'm also using a 1-wire Bosch sensor and it works good for me.

What brain are you using for FI? SDS? You running Alpha-N?

Cheers!

John N

[Guest Anonymous]

As I have 4 butterflies and I could not tune the system with MAP, so I went with TPS as a load sensing unit. It now runs as an Alpha-N system. It is a docile car on the road (when going to the races) and on the street it does everything I want. Perfectly tuned. I may install a Turbo over the winter, so, all I have to do would be to connect a 2 bar MAP sensor and play with the pad.

[Guest Anonymous]

(nt)

[Guest Anonymous]

In fact it is not really tricked, just the basics.

[Guest Anonymous]

If you are running a 02 sensor you can adjust the CO mixture with a multi meter by measing the voltage produced by the 02 sensor. I forget the range but it's like 450 mv or something like that for a correct mixture. Same spec as the 84 318

[Guest Anonymous]

URL: http://www.buy-secure.co.uk/gunsons_analysers_gas.htm

guy in the US for around $100. It works good on my Tii. You just stick the output up the tail pipe.

This is the email of the guy I bought it from:

johnabbott@bellsouth.net

There is a color tune system that is available from the same people at the website. It worked really well on my tri-carb Jag and it stands to reason it would work good on fuel injection also (provided your not color blind).

[Guest Anonymous]

I have the older version (readout is analog meter, not digital numeric display) of the Gunson Gastester CO meter, and it does not give me consistent results. The calibration point drifts every few minutes, and the CO reading varies with no change in tuning. I don't know if these limitations apply to the newer digital output version.

I also have a Split Second LED AFM with a 'wideband' O2 sensor in the downpipe just after the 2-1 merge. This gives more consistent results than the Gastester, but doesn't have enough resolution in the area of interest (2-3 % CO) to be useful for tuning my tii. The last LED is about 6% or more, and the penultimate LED is about 1.5%, so there's no way to distinguish 5% from 2%. It's fun to watch while driving, though. As others have said, an O2 sensor is designed to detect over/under stoichiometric ratio, not measure small changes near stoich.

I'll be shopping for a commercial CO meter.