Leaderboard

So here is what I ended up with on the OEM drum backing plate. Went with several 0.215 dia holes instead of one large oblong hole. I figured this was a reasonable compromise between venting, not weakening the steel too much, and doing something I had adequate tools for. When you add up the holes, it equates to a little over 2 in^2 of of passageway. Here a hoping It makes a difference! I opted not to drill/modify the AL drum since it already flexes so much at high temperatures.