336 Rear engine temps

[Richard]

New 336 owner here. I'm finding out where the 336 got it's reputation for a hot rear engine. I have new baffles, GAMI injectors, and new exhaust. When I close the rear cowl flap, cylinders 1 and 2 like about 450+ degrees. When cowl flaps open, 1 & 2 still like 420-430 degrees. What are some tips to keeping the engine cool? Here are my temps:

CHTs
1 443
2 449
3 436
4 449
5 391
6 391

Does this look normal to all you 336 owners out there?