Am I knocking?
 

Hi guys,

Im running a Rev MS3 with Flow Force 640cc and Innovate LC-2 on a otherwise stock NB2.
I'm using Revs basemap spark timings.
Around the 3k rpm, range I can hear a audible sound which i think is knocking.

Are those spikes knock or am I on crack? Logs are attached.
https://cimg5.ibsrv.net/gimg/www.mia...6ba9690ed3.png

Yes, that's definitely knock.

Though you may also be on crack. Not enough information to tell. :giggle:

Thanks Rev

I forgot to add, this is with 91 Octane.

I have a couple follow up questions:

1. Should I lower the ignition advance in this area? Based on a couple of your base maps that I have found, 22 degrees at 88kpa and 3000rpm seems on the low end in this area.
2. Should I install colder plugs? I'm currently running the stock BKR5E
3. Should I adjust the Knock threshold, the current one in your basemap seems rather high, 50% at 3k rpm, while this log showed knock at 7%
   1. https://cimg6.ibsrv.net/gimg/www.mia...165561048b.png

Thank you!

If you see knock on the log and you hear knock in real life, then you need to address the knock. If you decrease timing and it goes away then you have bad gas and should tune accordingly (22* in that range is definitely conservative), if it still doesn't go away then you will need to start troubleshooting for what might be causing it

I was thinking the same thing. I'm running 30* there with no knock in the log or my ears. 93 Octane and 9.0:1 compression '99 head. I do remember knocking at around 32* and low boost -maybe 120kpa- at 3krpm.

So from where I stand either you're not running real 91 octane, or something else is afoot. Even with the higher compression of the VVT this doesn't sound right to me.

Potentially did not set base timing on the MS with timing light?
Knocking at 88kPa, so spark plug should not be an issue. No boost involved on this car.

I didn't notice the 88kPa myself either. This is weird, you shouldn't be knocking at 88kPa/3000rpm with 22* of timing. Reduce timing and see if it goes away.

The timing was checked when I installed ms a few months ago. It was dead on.

I lowered the ignition timing in that area and the knocking went away. I guess this points to bad fuel.

I've been primary filling up at my local Costco. I'll try some other stations and report back

Thanks everyone.

Any new developments on this? Can you increase timing with better fuel?