I have a -6 that #3 & #$ are overheating at full power on takeoff. They go over 410 before pattern 800'. I have to throttle way back and let them cool for about 2-3 minutes then I can climb at will. I have tweaked and sealed the baffling all I can. Its the tightest baffling I have ever seen (and as an active AP, I see a lot of them). I installed an (temp) eight inch long 45 degree angle at the rear of the outlet tunnel and it seemed to help. So I then removed that and cut out a two inch by eight inch section of the rear of the tunnel trying to add outlet area. It made it worse. Now what.