Rear Cooling Development History ?

[ShinnickMark]

Hello, I'm a longtime Rutan Defiant guy looking to apply Defiant lessons learned to an upcoming 337 project.

Defiant had its own cooling challenges before I got that figured out by around 1999. That cooling was a patient project with numerous tests and re-shaping's at my base in Mojave before CHT's never got more than the mid-300's. That's one Centerline that really has done pure single engine ops.

I wonder if anyone might know some developmental history before someone eventually decided that 336/337 rear cooling was finally figured-out. Just looking at it...I'm not so sure it ever really was. I'd love to hear where the most typical problems temps usually show up.

Maybe I can also hear about when did the upper inlet scoop appear within Skymaster development in relation to when the rear cowling's annular shape?

Thanks.