AFR's at speed - open loop
 

Just for fun I did a log of a high speed run today & thought it may be of interest .
First part of run is in 6th gear then I stopped & turned around giving it full throttle in 1st & 2nd before holding in second while waiting to pass a car .

Note how closely related to throttle posn. the AFRs are . I have about 10% fuel trimmed through my piggyback in most load points you see here.

Also got my post count to 1000 with this thread - where's my tee shirt ?

Don't mean no disrespect but...huh?

It's a cool chart but I'm not sure what 10% fuel trimmed means relative to a stock '8

throttle release causes less fuel injected = lean AFR

Look up NA tuning experiments on this site. It really helped me during my tuning days.

So you're doing 10% reduction all the way? Even below 5800 rpm? I wouldn't touch fuel trims below that range unless you want your car to start injecting more fuel than you need in cruising speeds (in the long term)

I'm pretty confident I have only taken fuel out in open loop which by my tests is at 4000 rpm+ & 30%+ throttle . It is possible to be in closed loop over 4000 & under 30% but only very rarely. EG when going down hill .
Long term fuel Trims shouldn't be affected by these rare occurances .

which version of the scanilizer are you using? i cant seem to get the fuel open closed to work.. maybe that i am using the dig gauge option..

beers :beer:

version 1 - you'll find it on the 'fuel system status' gauge option .

what dial option are you using?

beers :beer: