It is very difficult to mechanically tune a carburetor to the fuel curve accurately over all operating conditions and loads. You can get it very close at some points in the curve but you cannot get it close enough over the whole curve. A carburetor cannot "adjust on the fly" by itself. If it had some kind of adjustable component like the Lambda system on the mechanical K-Jet it could be more accurate. Remember, the K-Jet is a mechanical fuel injection system with an electronic control (Lambda) grafted over it to add just enough fuel to get the mixture right. The carburetor was just too finicky to hold it's tune. That is why it lost out to fuel injection. Eventually fuel injection systems became purely electronic. Now we see them moving to direct injection like on a diesel. Changing a jet just moves the whole curve up or down. A carburetor has no ability to compensate for temperature or air density. Unless it has some kind of metering jet hooked up to the manifold vacuum it can't sense load either. David Teitelbaum --- In dmcnews@xxxxxxxxxxxxxxx, Marc Levy <malevy_nj@...> wrote: > > Sorry Bill, I don't trust "turning a screw" to achieve proper AFR in all running conditions and fuel types.. Heck, I don't trust it to achieve proper AFR in *ANY* condition! > > I don't think anyone else should either, especially if they are still running a catalytic converter. > > http://en.wikipedia.org/wiki/Air%E2%80%93fuel_ratio > > But, here I am.. Sucker for toll bait AGAIN! Shame on me. > > > --- On Wed, 4/11/12, content22207 <brobertson@...> wrote: > > > I can jet a carburetor as rich or as > > lean as an owner wants. I can jet it so lean the engine > > predetonates (I've done it to my own car while experimenting > > with jet sizes). It's the same effect as turning the CO > > screw on K-Jet too far in either direction. > > > > Bill Robertson > > #5939 > ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: dmcnews-digest@xxxxxxxxxxxxxxx dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/