Those look like Jeff's old ones. There is some debate at to what flows better, those or the Hardin Marine header logs where the bolts go through the entire log. But even if those flow a little better, you still have to take them off to change the spark plugs and all the other you don't. Maybe an engine compartment like Cliff's with more room could get to the plugs from the bottom. The Glastron has zero room to get under the pipes.
Good find though.
