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PRO AND CONS OF OPEN LOOP

Posted: Mon Aug 28, 2006 9:37 pm
by Profoxcg
can someone please tell me what are the cons and pros of open loop and why does it even exist if the right mixture is 14.7:1 ?

basically the reason I ask is so that I can learn how to tune. and my first experiment is a tune for better fuel efficieny and I just watch the video the Doug did I think.

Don't I run the chance of running too lean or too rich when ever I run open loop - if so why even do it ?

what are some values that should wave a ref flag on eithe side of the spectrum (lean versus rich) - for example if If I see anything above 15.5 its too lean ect.

Posted: Mon Aug 28, 2006 11:26 pm
by Razathorn
The mixture must change at full throttle and richen up. Maximum power is made around 13.2:1 a/f. As you make more boost, you need to add fuel to keep the cylinder temperatures in check, so boosted motors run richer at around 11.5 - 12.0 a/f. Closed loop is genreally just for keeping the a/f at 14.7 so the cat will work as best as possible and you will get good fuel economy when cruising.

Wayne