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rkreigh · 10-08-2019

the LT5 seems to have fantastic knock resistance. I enjoyed Marc's presentation about the knock events and how they drastically affect timing and very slowly return timing so the car feels very lazy

When I got the LSV, Larry left the race chip in it and it had 31 deg timing and ran around 12 to 1 compression and ran just fine on pump 93 gas. I ran some high octane unleaded at the track and saw no improvement and indeed no knock issues data logging with Ease.

Cam timing of course helps as the cyl pressure doesn't spike up at lower rpms and the high rpms as Graham mentioned are pretty forgiving

I got a bit "knock paranoid" from my old days of buick turbos as we "drove over the crank" every now and then from knocking the bottom end clear through the oil pan.

I'm very impressed at the efficient combustion chamber and knock resistance of the lt5. It allows much higher compression ratios on stock pump gas than other engines.

10-08-2019	#27
rkreigh Join Date: Jan 2004 Location: Alex VA Posts: 1,080	Re: Knock. A question for Graham or Marc the LT5 seems to have fantastic knock resistance. I enjoyed Marc's presentation about the knock events and how they drastically affect timing and very slowly return timing so the car feels very lazy When I got the LSV, Larry left the race chip in it and it had 31 deg timing and ran around 12 to 1 compression and ran just fine on pump 93 gas. I ran some high octane unleaded at the track and saw no improvement and indeed no knock issues data logging with Ease. Cam timing of course helps as the cyl pressure doesn't spike up at lower rpms and the high rpms as Graham mentioned are pretty forgiving I got a bit "knock paranoid" from my old days of buick turbos as we "drove over the crank" every now and then from knocking the bottom end clear through the oil pan. I'm very impressed at the efficient combustion chamber and knock resistance of the lt5. It allows much higher compression ratios on stock pump gas than other engines.