I designed the heat muff to take in air under the hot cylinders and around the first exhaust down pipe. It will flow around the collector piple until exiting out the bottom at the end of the muff. I decided not to install any baffles or springs in the interest of good flow. I think by drawing air from the heated cylinder fins the heating effect will be adequate. If not, I'll cry for a bit, then install some baffles ;-)
