I think you have the right idea, it's just that your numbers are backwards. The higher the number, the closer you are to detonation. Of course the factory doesn't want that so they are going to set the tune far away from that (11-12.5). The higher the number, the more cold air is being forced into the pistons, allowing for a better ignition, resulting in more power.

The link explains a it of it...

http://www.tricktuners.com/widebands..._explained.htm


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Haha, cool. I think we were on two different pages before. I get what you're saying now.

Just to clarify my statements, if you noticed a few posts up, I was talking about daily driving and lower-end power improvements, granted I did mention dynos and such so I understand the confusion. Though, I was talking about the overly lean tendencies of the mixture from the factory under normal driving conditions, and even WOT in the low-end, which can be seen in your dyno chart as the mixture starts out in the 16s or so (?) and declines. But yeah, now that we're on the same page I understand what you meant.

Nissan's tuned the motor oddly low-end and high-end. Clearly, as your chart shows, the mid-range tends to need the least work with these cars. Ah well.

Any drawbacks to running it closer to high-11s like you are? How does it feel once the oil is up to temp and intake temperatures increase? One thing I've noticed is that these motors don't like their timing messed with, I did some minor tweaking of the timing with UpRev's personal assistance and the motor did not respond well to it at all once the oil temps were 180 (I have an oil cooler). When the car is cool or the weather is cold, it ran fantastic, but other than that...the ECU begins to pull so much timing the car practically felt like it was in limp mode. No throttle, no power, nothing. UpRev discarded that tune and I flashed it to my current ROM with an idle adjustment to 850RPM added.

This is what my tuner just said. Lemme know if it is rubbish haha.

"13 is a very standard AFR for normally aspirated.
I would run an old 2-valve pushrod engine at 12.5 because their combustion chamber design is really poor and detonation can happen fast. but today's 4 valve engines have advanced combustion chambers that are designed to prevent detonation from the start."

@ conor1123: 13 for an NA motor isn't technically "standard" per sey from factory. After a tune for power then yes, it is what a lot of NA cars aim for since it is a good balance of power and detonation resistance. As i stated earlier, it's what i am going for after my tune

@ Arnold K.: The lean factor is what every vehicle is tuned for under basic driving. Better fuel economy is achieved from a leaner mixture and with it tuned for less throttle and under less load, detonation is assumed to never be an issue for factory settings. There are really no repercussions for running as rich as the stock map has it set at other then burning more fuel then technically necessary unless it is ridiculously excessively rich in which it would flood the motor. It does run cooler then a higher AFR for a little bit but it does lack power. Its more of a "safety net" and for your average driver then someone trying to maximize power gains.

Ok one thing to clarify, AF Ratio does not control the "air forced into the piston". That is controlled by the throttle valve. AF Ratio injects fuel based on the amount of air measured flowing in.

As for maximum power, it's a combination of AF ratio and iginition timing. The key is to avoid detonation and leave a certain safety margin.

That's pretty much what I meant, I just said it retarded :)


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