I was looking at getting a PNP and learning to tune.
Are any of you using the knock detection on the Megasquirt to tune?
I was wondering this as I would be doing street tunes and I could log then adjust over and over.
Knock Detection
Knock Detection
Aren't you tired of "everything" because race car.
-
- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
Re: Knock Detection
I am not! I've been wanting to get it working myself! Maybe MattCramer can chime in on how this works on our mspnp2 systems. I know it is physically wired in through the wiring harness still, but the megamanual seemed rather vague. I don't know how I feel about simply turning the feature on and hoping it works.
- Matt Cramer
- KA-T.org Sponsor
- Posts: 934
- Joined: Mon Sep 15, 2008 5:34 am
- Contact:
Re: Knock Detection
There's two parts to the MSPNP knock circuit.
1. A headphone output that lets you listen to the filtered knock signal. It will show up as a high pitched almost beeping sound through the filter. Useful for tuning if your engine is knock limited.
2. The analog circuit that the ECU uses to pull timing. I recommend dialing it in so a conservative spark map won't make it trigger. Not something you'd want to use as a primary tuning tool, but it could help if you have something unexpected like a tank of bad gas...
1. A headphone output that lets you listen to the filtered knock signal. It will show up as a high pitched almost beeping sound through the filter. Useful for tuning if your engine is knock limited.
2. The analog circuit that the ECU uses to pull timing. I recommend dialing it in so a conservative spark map won't make it trigger. Not something you'd want to use as a primary tuning tool, but it could help if you have something unexpected like a tank of bad gas...
Matt at DIYAutoTune.com - Megasquirt ECUs, fuel injectors, wideband O2 sensor systems, and more
Nissan plug and play engine management now in stock!
Nissan plug and play engine management now in stock!
-
- 240sx Wannabe
- Posts: 118
- Joined: Sat Aug 17, 2013 10:38 am
Re: Knock Detection
Anything to set up or adjust with either of these options? Or simply turn on and go. I was under the impression that knock sensors pick up and filter certain harmonics, so determining that harmonic seems a little scary. Like if I we had to induce knock to get it working
- Matt Cramer
- KA-T.org Sponsor
- Posts: 934
- Joined: Mon Sep 15, 2008 5:34 am
- Contact:
Re: Knock Detection
The frequency is physically set in the hardware. However, there are several trim pots inside the MSPNP you need to adjust. See the MSPNP manual for details: http://www.megasquirtpnp.com/docs/mspnp ... &isModel=2
Matt at DIYAutoTune.com - Megasquirt ECUs, fuel injectors, wideband O2 sensor systems, and more
Nissan plug and play engine management now in stock!
Nissan plug and play engine management now in stock!