LM-1 Wideband for carb tuning

[koolaid_kid]

Here is the exit. It is at the far right and goes back into the exhaust stream for a "venturi" effect. A much simpler method could be developed; I suspect they did it for strength as much as anything.

Hope this helps.

 

[Guest]

Here is the exit. It is at the far right and goes back into the exhaust stream for a "venturi" effect. A much simpler method could be developed; I suspect they did it for strength as much as anything.

Hope this helps.

What is that taped pipe wrapped with a towel?
Thanks!

 

[Guest]

Thank You and yes it helps. When I get bored at work again tomorrow I will modify the pic I made and hopefully you can double check it for me.

Thanks again.....
Dave

 

[koolaid_kid]

What is that taped pipe wrapped with a towel?
Thanks!

No. That is the exhaust clamp with the sensor installed, resting on some wires that have been wrapped in a towel because they were rubbing on the tank and sidecovers. This was just to get everything ready for the pictures.
When I download the log files to my pc, I have to power up the LM-1, which requires the O2 sensor. So I rest the lot (clamp, sensor, wires) on shop towels. It is a heated sensor and gets quite warm to the touch.

 

[2BRacing]

Koolaid Kid

Thanks for sharing these photos with us. Although I do not have such equipment, I am very interested in this subject, as I am a firm believer in using technology and Nessism's philosophy of "to measure is to know". So why not combine 80's technology (our GS carbs) with modern digital measuring technology (wideband oxygen sensor)? Other members such as Posplayr have also used the technique.

I would love to try and make up a system using a sensor from a car and the venturi as per your photos, and some digital data interface to a PC.

Could you tell us how you proceed after collecting the data and downloading it to your PC? Perhaps show some screenshots of the data, and tell us how you interpret it.

I would like to suggest that you use this opportunity to draw up a how-to "tutorial" on this subject and have it placed on BassCliff's site. That would be "super-cool"!

Thanks!

 

[2BRacing]

Basically, the tube that slips into the tailpipe has two channels, the entrance hole I already showed, and then an exit channel. Most likely that is a bit of overkill, but that is the way they designed it.

Koolaid Kid

So just to clarify the design of that venturi tube, am I correct in understanding that the inlet tube going down inside the venturi tube is totally closed off and separated from the return path leading back to the exit hole?

The design could just as well have two separate tubes for inlet/exit, instead of the (difficult to make) enclosed venturi tube with separate channels inside, right? Or am I missing something here?

Thanks!

 

[Guest]

Koolaid Kid

So just to clarify the design of that venturi tube, am I correct in understanding that the inlet tube going down inside the venturi tube is totally closed off and separated from the return path leading back to the exit hole?

The design could just as well have two separate tubes for inlet/exit, instead of the (difficult to make) enclosed venturi tube with separate channels inside, right? Or am I missing something here?

Thanks!

Koolaid Kid, can you check my updated pic showing what I think is the air flow through the venturi tube? This would help clarify things for 2BRacing and Myself. When I get a LM1/2 I will be making my own tube, most likely from copper pipe.

Thanks,
Dave

 

[posplayr]

Koolaid Kid

Thanks for sharing these photos with us. Although I do not have such equipment, I am very interested in this subject, as I am a firm believer in using technology and Nessism's philosophy of "to measure is to know". So why not combine 80's technology (our GS carbs) with modern digital measuring technology (wideband oxygen sensor)? Other members such as Posplayr have also used the technique.

I would love to try and make up a system using a sensor from a car and the venturi as per your photos, and some digital data interface to a PC.

Could you tell us how you proceed after collecting the data and downloading it to your PC? Perhaps show some screenshots of the data, and tell us how you interpret it.

I would like to suggest that you use this opportunity to draw up a how-to "tutorial" on this subject and have it placed on BassCliff's site. That would be "super-cool"!

Thanks!

If you go to the Innovate website you can download teh logworks software.

http://www.innovatemotorsports.com/support.php


Then if you go to this link there is a log file from one of my final runs that you can download and look at using the Innovate software.

http://www.innovatemotorsports.com/forums/showpost.php?p=71932&postcount=167


I have more channels of course.

On the sniffer I made (found plans on the web), I have more of a straight "flow through" design made from a straight piece of steel pipe and some copper tubing and couplers. It seems to have very little lag and or effect on the exhaust flow.