Italianjoe1

iTrader: (6)

I see we can adjust the range that the car uses the knock sensor, anyone know the reason the factory setting ignores it over 6400rpms?

karletto66

Also UPREV ignores knock ar high rpm in my info.
May be the ECU si working in that way and is not possible to change with these kind of maps.

0jiggy0

iTrader: (13)

I believe it was something about engine noise. Where you would be getting false readings.

karletto66

May be...
IN UPREV site they have a schematic for a "knock detector" wich take out noise using electronic filtering...

Ziggyrama

iTrader: (15)

The knock sensor is nothing but a microphone that is designed to feed the ECU sound data. The ECU looks at the harmonics and if it sees a particular signature, it will interpret it as knock and act accordingly. If you look at the sound recording of a ping, it has a specific pattern that can be identified by a computer. It's important to note that this is all based on analog signals. So, noise is an important factor. If you get too much noise, the computer will not be able to reliably recognize knock and will likely trigger false positives. Looks like Nissan determined that above 6400 RPMs, the engine makes too much noise and the knock senors becomes unreliable. I would trust this setting.

Italianjoe1

iTrader: (6)

I figured it was interference, it just sucks that we can't use it up top. Hoped maybe someone had more solid info, guess i'll just hope and pray for now lol.

Italianjoe1

iTrader: (6)

On the same topic, and idea how the timing number in the computer relates to actual advance? I know the car isn't running 38 degrees of advance at WOT...

0jiggy0

iTrader: (13)

Read the tuning guide. Even the Uprev guide applies. Nissan computers don't calculate using actual timing. They use a theoretical number that represents "burn time" its pretty much 2 points on that system = 1 degree of timing give or take. It isn't exact.

But the gist of it is the higher the number the more timing your running.

You can get some nice seat of the pants gains by upping it 4-5 points from around 4k+ in the last 2 ipw tables.

I wouldnt go any higher then that without verifying it on a dyno.

This of course is guessing your running 93 octane.

There's no real reason to go leaner then 12.5 AF or so on WOT. The VQ seems to like more timing, more-so then a leaner mix, NA at least.

Some people like to go near 13 AF, but that's up to you. All of this should be verified on a dyno of course bla bla.