Originally Posted by Stu @ M Developments
Originally Posted by the original
I didn't think catalytic converters changed the lambda reading, only removed the CO and HC
The whole composition is apparently changed and whilst i dont understand the checmical dynamics of the modern three way system, i do know from experience that you cannot accurately read the gases after a catalyst. On modern turbocharged cars the catalysts fitted are so impressive you cannot read more than about lambda 1, even flat out at 350bhp. Whilst this is a great achievement, it makes a simple setup and chip a real ballache.
there is not a gas analyser on the market that can read as far as lambda 2 .....
Lambda 2?
A decent one like mine will read down to lambda 10.
http://www.labcell.com/product.asp?id=17&pr=46
(If so, then the idle lambda should be measured with a gas analyser not an oxygen sensor)
A Gas analyser is no better with a catalyst. The fact remains to see what an engine is producing you must look BEFORE the catalyst. Thats why, as mentioend earlier, the lambda sensor on a production car is always located BEFORE the catalyst.
Stu that's what I'm saying, what
you have is not a gas analyser
a true gas analyser will measure the same afr after a cat. as what's produced in the engine
I thought they may have been using a gas analyser (like in an Mot station or most garages) but I guess it wasn't, just a lambda gauge
I think Alex F understands what I'm getting at