if the bowls are the round part where the piston comes up and compress's everything than if you mess with them are'nt you lowering your compression. Rich
rich, the bowls are the area under the head of the valve (the inside of the head) this is the area were the air and fuel come through and exhaust exits through. not in the combustion chamber.
Here's a pic to show the bowl area. It would be the area above the screwdriver up to where it makes the left turn. you can see the valve guide area nicely in this crosscut.
