Knock Link Reliability Poll

Hey all, I've got an Autocross tomorrow and I'm getting the car ready. I've been tuning the ignition timing on my v6 Camaro to try and get as close to MBT as the knock threshold will allow and I've begun to distrust my factory knock sensors a little. During a couple WOT runs I had a little knock activity so I focused on those areas by backing the timing off a little and running it a little richer. For a few runs no knock was detected by either the light or the factory sensors. Over the course of several more runs I noticed those same areas would report being either completely fine or having some knock activity at varying degrees at seemingly random occurrences.

Since my initial "fix" the knock light hasn't gone off once, and I'm inclined to trust the light over the factory sensors after reading unilaterally positive reviews on it. But my question still remains, how good is it? Let me know what you guys think, should I continue to heed the warning of the factory sensors with 80,000 miles on them, or is the brand new Knock Link more accurate?

Autocross is really brutal in terms of heat soaking components, which can lead to knock in RPM/load areas which do not knock during driving without the heat soaked condition, so that's something to keep in mind. It's not always fully accounted for in IAT and ECT comps, or perhaps not accounted for sufficiently.

Audio knock detection in general isn't totally foolproof. I've not used a system that I agreed with 100% of the time while listening in myself, but that unit is one of the good ones.

Here's my shameless plug for the product I just launched that might bridge the gap between audio knock detection and visual warnings for you.

https://www.youtube.com/watch?v=yfvrSEdrPU0

I've found the knocklink to be pretty reliable on most NA engines, less reliable as the engine gets more serious and mechanically noisy (forged pistons, mechanical lifters etc) as well as high boost engines where the noise profile really increases with boost.

The knocklink listens to alternator ripple on the power supply wire along with the knock signal to build a 2D profile of engine noise level Vs RPM, so it doesnt compensate for noise that varies with boost well.

Your factory system should in theory be better since it will likely factor in more than just RPM and will be doing windowing etc, but the problem is sometimes they are calibrated to work within a fairly narrow design intent. For example I have heard some cases where an OEM system started reporting false knock events after a change to aftermarket suspension bushes.

Ya my Talon has a very loosely built forged motor and the factory knock strategy pulls like 10 degrees of timing while I'm cruising in vacuum. I had to disable it and just tune it by ear. There's no DSP out there better than our ears and brains :P