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enkeivette · 10-19-2014, 11:48 PM

I was reading another engine building article, and it made me wonder if what I've heard from fellow forum shit talkers is true.

Quench. The importance is turbulance in the cylinder for fuel and air mixing. To promote better combustion and avoid hotspots. I had many shit talkers warn me not to decrease my CR with a thicker HG for fear of fucking up my quench. But I did it anyways and my motor has never run better (it has also stopped melting pistons, knock on wood. It seems to me that my gigantic belt driven snail that blows more air than a leaf blower at 650 rpm would have to do a pretty damn good job of forcing the air and fuel to mix anywhere at or above idle speeds, prior to it being quenched. So, with forced induction does it really matter?

Overlap. Ill keep it simple. With NA, the higher velocity air jamming in to the cylinder compensates for what leaks out. So, ya, with more overlap, more boost will leak out. But who is to say that isnt more than compensated by the boost being rammed in those last few nano seconds? Thoughts? Science? Shit?

10-19-2014, 11:48 PM	#1
enkeivette Super Moderator Join Date: Dec 2007 Posts: 6,850 Tweet	Importance of quench and overlap in a forced induction app. I was reading another engine building article, and it made me wonder if what I've heard from fellow forum shit talkers is true. Quench. The importance is turbulance in the cylinder for fuel and air mixing. To promote better combustion and avoid hotspots. I had many shit talkers warn me not to decrease my CR with a thicker HG for fear of fucking up my quench. But I did it anyways and my motor has never run better (it has also stopped melting pistons, knock on wood. It seems to me that my gigantic belt driven snail that blows more air than a leaf blower at 650 rpm would have to do a pretty damn good job of forcing the air and fuel to mix anywhere at or above idle speeds, prior to it being quenched. So, with forced induction does it really matter? Overlap. Ill keep it simple. With NA, the higher velocity air jamming in to the cylinder compensates for what leaks out. So, ya, with more overlap, more boost will leak out. But who is to say that isnt more than compensated by the boost being rammed in those last few nano seconds? Thoughts? Science? Shit? __________________ I <3 forced induction.