Rod, I have used the red,black,and the blue one as long as there "non-stick" and seem to be fine....I run race gas so alky may be different....I really don't like the plastic bowel screw gaskets as I have striped a bowl screw to try to get it to stop leaking...The thick washers seem to work better for me as they have some "sqush" and keep things tight and no leaks.......And thats IMO
