O2 sensor location for datalogging

On Friday Im gunna order an Innovate LM2 Dual sensor AFR meter. A great deal of technology in the hands of a neanderthal. I will use this on my 1100. As you know they have bungs in the headers,requiring adaptors, but would I get a better /quicker result if I put bungs in the headers the same distance from the valves that dont require adaptors ?.

Charlie J wrote:

As you know they have bungs in the headers,requiring adaptors, but would I get a better /quicker result if I put  bungs in the headers the same distance from the valves that dont require adaptors ?.

Huh?




.

Use the existing bungs,down by the sidestand mount, or add 2 new ones,so the sensors screw into the headers not adaptors, so they are both x distance from exhaust valves

Since you are going to be logging both sides simultaneously, stick bungs in the headers about 6 inches from the midpipe end.


.

Hoping not to confuse the issue my friends, but my exhaust guy stated wide band sensors for AFR tuning on (the bum) dyno should be about 6" from the exhaust valve.

But don't ask me why.

The distance isn't going to be that important as long as the way the signal is interpreted is relevant.

When the exhaust valve opens combustion is still occurring but the heat involved is no longer sufficient to provide worthwhile work and neither is it hot enough to cause damage to the relevant parts like valves and seats.

The idea that there is some *Ideal* distance assumes that some sort of magical reading can be taken at that point based on time and distance involving the exhaust pulse. This is of course silly as both the gas speed and the timing of the pulses are going to differ greatly depending on a large number of factors such as engine speed, load and throttle position.

This sort of thing is only going to be used if it is also combined with a lot of other observations, IMHO most importantly plug readings.

Plug readings will tell you exactly what is happening IN THE COMBUSTION CHAMBER rather than the exhaust pipe, and that is what really matters! I couldn't give a fuck what is happening in the pipe! That charge is 'Exhausted'! That's why it's called 'Exhaust'! But you can, with experience, extrapolate from those readings what may be happening in the chamber but it will be inconsistent unless you ALWAYS use the same distances from the valve.

Closer to the valve? More residual hydrocarbons Nd higher oxygen content. Further away? More complete combustion.

The main thing is to not have the sensor so close to the valve that it will be overheated and not so far that combustion evidence is unreliable, (In theory you could put a WBO on the rear number plate and hope that you'd get some form of feedback! Some experts seem to do just that! .

At the end of the day the thing is to get consistent readings and use them in conjunction with other observations. Anything else is just throwing darts at a wall and hoping you hit the bullseye.

Pete

Charlie, I am the FIG. Do as I say and install the bungs six inches from the pretzel.

I might not be the sharpest knife in the drawer,but I have enough nouse to figure out that when the bloke with probably the most experience on the planet,in the field about which advice was sought, answers your question then eifher heed that advice or argue it intellegently and reasonably. Who am I to argue with the FIG. 6 " from Pretzel it is. Where the Factory put their bungs. Cheers.

Let us know how you get on Charlie. While I'm happy the Rosso is as good as it gets with beetles magic on board, I have more plans for a new zorst on the Verde GRiSO.
Good Luck

I figured I'd get a response.
That means I just learnt something knew....................... again.
Thanks Pete.

Somewhere in here, Charlie:


[You must be registered and logged in to see this image.]