Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: twistedtree on January 19, 2012, 02:20:05

Title: Setting mixture - CO vs Air/Fuel metering?
Post by: twistedtree on January 19, 2012, 02:20:05
I want to check the mixture on my cars across their operating range.  To do it properly I need to be able to measure mixture at various speeds and loads, and I'm interested in understanding the tradeoffs between using a CO meter and using an air/fuel mixture meter.  There was a great article on the subject in Pagoda Notes Vol 4, Issue 1 doing this with an air/fuel mixture meter.  But CO meters are also effective, it would seem?

If you were going to invest in one of the two, which would it be and why?
Title: Re: Setting mixture - CO vs Air/Fuel meeting?
Post by: Cees Klumper on January 19, 2012, 08:55:30
I have a good basic (Gunson) CO meter that I use to set idle mixture level. But I don't think it is useable to set mixtures under load. Must admit I don't recall the Pagoda Notes article but this is what I know?
Title: Re: Setting mixture - CO vs Air/Fuel meeting?
Post by: twistedtree on January 19, 2012, 12:07:15
Yes, my past experience with CO meters (very long ago) was setting idle mixture too.  I haven't kept up with test equipment at all over the intervening 30 years.  My current default will be to get an air/fuel mixture meter because I know it can record data over a run with the car which is key to setting mixture in the various ranges.  But it seems that at least in theory a CO meter should be able to do the same thing, so I want to remain open to that as an alternative.  And perhaps there are other pros and cons as well.  I've just been away from it for too long to know.
Title: Re: Setting mixture - CO vs Air/Fuel meeting?
Post by: Cees Klumper on January 19, 2012, 17:22:58
The reason I think the CO meter I have would not do the job is that it requires inserting a probe into the exhaust to measure the mixture. Once you start driving a car, I think the wind turbulence around the exhaust would prevent taking an accurate reading - but I could be wrong, just never really looked into it.