I know I just threw out a long post and people are like "so what, what reading I believe? what should I do?" Let me throw in there that I'm all for having more instrumentation if you're willing to tolerate the science-experiment factor. If you can get a backpressure sensor, a pump-current type (Bosch, NTK) sensor in there, EGT, whatever, go for it. The question is--well now what do I do with this information? How do I interpret it and make decisions?
Quote:
Originally Posted by s2d4
@ jamesm looked into this when he did full close loop.
It's ridiculous how far off the previous forum golden childs had it so wrong.
A lot of the old dyno plots prior to 6-8 months ago had 13-14 AFR at WOT.... |
I have no doubt that one sensor in one location said one thing, another sensor in another location said something else. But what happened
inside the cylinder ? We can make some general statements, but without a lab worth of equipment, I say: who knows? And even in a lab, it doesn't always reflect the reality of what's happening in the vehicle on the road.
One of the root causes of all of this hand-wringing are widely accepted internet rules of thumb for tuning. Rules of thumb are there for a reason, and they are still grounded in accumulated experiences of many people. But think about why we're having this debate.
Perfect example: "Don't go leaner than this AFR," subtly implying that you're a bad tuner/you don't know what you're doing/you're going to blow your car up if you are outside that range. That's not a bad kind of rule. We need rules like that, or nobody would accomplish anything doing day-to-day work. The natural result then becomes: "my x sensor at y location says I'm at 11.5, but what if I'm really at 12????? do I have a bad tuner/are people going to accuse me of being an incompetent tuner? Is this engine going to blow up?"