Knock retard question


Aug 17, 2010
New to turbo Buick tuning. I know what the issue is - to much boost. I have been successful in lowering the boost. My question is....during the lowering and testing phase the car ran into a few episodes of knock retard. Most were 3.6 with one going as high as 5.8. All were in 1st and 2nd gear. All were very short in duration - under 5 seconds.

My question is how bad is this on the motor? In reading all of the data on this web site it appears this is a normal part of tuning and as long as it is not prolonged, typicall no harm is done.

Can some of the veterans confirm my thoughts?
Tune for 0 knock and it will live much longer....

Yes agreed. However in the process of getting to 0 I experienced some knock retard. On a scale of 1-10 how bad is short term nr from 3-6 degrees?
Was this knock during the shifts? You know what kind of chip you're using? How much boost are you at now and what octane fuel?
Not sure on the shifts. TT Chip is 92 octane, 15-18 boost spec. Just purchased the car. Boost was set at 25 lbs. Also cam with 110 chip. My guess is the chip was changed and the seller forgot to dial back the turbo bleed valve. Dialing back to 17. Will do testing today to verify boost and 0 knock. Running 93 octane.
It's best to not have any knock, period. Once the knock sensor starts detecting knock, it starts pulling timing (the number you see on the Scanmaster) but the damage is already being done.

I'm guessing this is the car you just bought?

If so I don't see anything about an Alky kit on that car. If you want to run 25 psi on 93 you NEED that alky kit...unless you want to damage the engine.
Use to be a Florida car. Now in Michigan. High boost readings are in cooler air temps. 40-50 degrees in MI. Will cooler air increase boost pressure?