I saw a YouTube video by GadgetmanNebraska1 titled "16.5 hp. BRIGGS AND STRATTON lawnmower gains 60% efficiency" in which he says "we've done groove on a 16.5 hp that I put on the forums" but he doesn't say which forums nor what doing a groove means. Someone left a message asking him but there's been no reply. Does anyone know what he's talking about?
Doing a "groove" cut on an engine is something that is done to the head. Supposed to give it more complete combustion. Some guys do it with a drill at home. Others take it to a machine shop. It's a groove about 1/16" deep cut from the edge of the head just inside where the head gasket fits. Don't want to cut a hole where the gasket will blow out. Then up nearly to the spark plug hole. I don't understand the thermodynamics of the improved efficiency, but many claim it helps boost horsepower and better burn etc.
