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Road tuning a known knock limited engine

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What is a safe reduction in timing once you start to see knock in a knock limited engine? Pull 5* once you see knock?

What engine and setup?

If you have knock, removing 2-6 degrees of ignition timing is usually enough to eliminate it.

It is a GM 3800, NA, cammed, intake/exhaust, 10:1 static comp and i think the Dynamic is 8.4:1. I do not currently have knock, but its a e-tune im just now optimizing.

On a N/A engine that will be used on the street I'd try and keep a margin of 2-3 degrees from knock. You need to be careful however because you're likely to get some occasional knock activity logged on even a well tuned engine. Trying to eliminate ALL knock activity in the scanner (I'm assuming you're using HP Tuners or similar) is actually going to give you an overly conservative tune that will just cost you power everywhere. What I try and achieve is a tune where I'm not seeing consistent and repeatable knock in the same load/rpm zones.

As a side note you'd probably be blown away by how much knock GM apparently find allowable in the stock calibration on even a reasonably powerful engine such as their supercharged LSA.

I'm aware of their "acceptable" knock practice from scanning my other stock 3.8s, but I knew that's not how I wanted to approach the tune on this car.

Thank you for the responses.

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