The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Are BBC engines free spinning or interference engines

**Steeveedee** · 02-28-2020, 10:14 PM

SBC engines are also interference engines, BTW. Those little crescent moons in the pistons are only there to prevent contact between valves and pistons at high enough speeds. If the timing chain goes, it's going to be a mess of bent valves.

02-28-2020, 10:14 PM	#3
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,182	Re: Are BBC engines free spinning or interference engines SBC engines are also interference engines, BTW. Those little crescent moons in the pistons are only there to prevent contact between valves and pistons at high enough speeds. If the timing chain goes, it's going to be a mess of bent valves. __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA