You need a series 2 ems to use the knock sensor reliably (that's what evans said). If you have that, there was a thread in the AEM forums on how to make the check engine light up if knock is detected.

 

i dont see how it matters what aem box is in the car. knock sensor is 0-5v voltage. it detects vibration and converts it to voltage. as the rpms rise theres gonna be some vibtration detected.

my 1051u has a knock sensor calc table, and as rpms rise you allow more knock voltage before it starts to pull timing.

the sensor itself isnt very precise. but its enough to at least know kinda whats going on.

for instance, at 8500 rpm i see at most around 2.2 volts of peak knock voltage. if one day i see 3+ i know theres somthing weird going on.

you can set aem ems up that if knock goes to high it will use one of those outputs to illuminate a light.

or if you have aem serial gauges just have knock voltage as one of the displayed sensors and set up an alarm on it.

 

Check out joeyballs turbo build thread, evans chims in about knock using the new series 2 ems. I'm pretty sure he said it's hard to set it up on the series 1 for whatever reason.

 

For whatever reason, it's probably easier to recognize true knock on a NA/SC setup rater than an all-out turbo car; likely too much 'noise' with ~600whp!

 

basically what he said

I know you can make it a shift light but I'm not sure you want a "check engine" light flashing at you all the time, that would be a little disconcerting

 

I'm willing to bet you have a sleeved block, showing that 2.2 volt range. My factory block would show up to 3.5 volts, but after sleeving I'm betting the block's natural resonance frequency is different and thus the knock sensor isn't as well calibrated to the proper frequency of knock for the sleeved block now.

My sleeved block (Laskey / Benson) shows a max of 2 - 2.2 v with a conservative tune. ~14 deg timing after tq peak at 14 PSI, 2.0L, 9:1 CP pistons, Pauter rods, etc. GT3076R and Full-race / 3" exh.

Welcome additional thoughts and build specs / what knock voltage you're seeing.

 

he's got a bone stock motor. if you get aggressive with the timing you'll see more knock voltage. these motors can make a decent amount of power without a lot of timing so you gotta check everything out on the dyno and make sure the timing your running is actually worth the power. you may find that you can take out a few degrees and not lose much power but lower your knock voltage a lot.

 

My timing starts out at 6 deg when full boost comes on at 5100 rpm and peaks at 19 deg at the top on 110 race fuel. My knock volts are pretty consistant at 1.2 volts and has just a couple quick 2.0 volt spikes but its just noise according to my tuner/friend.

 

yeah if you want to see your noise floor you can do a dyno run with very little timing. you'll end up with low voltages slowly increasing towards redline and that's your noise floor. basically then you know you can ignore anything in those voltage ranges.

on camuman's car we played around with timing a lot and even with fairly advanced timing the voltages were pretty low, maybe 3V max, but never any audible knock or knock we could feel. ultimately it ended up getting tuned to a pretty conservative timing advance and that's where it made the most power anyway.

 

Wow! 3 volts on the knock would worry me. Me and my tuner dont like to see any spikes above 2.5 volts. If its just a quick blip its cool but if there are several at that voltage range, we back it off.