One thing I want to try with the Spit & Hurri rads is to open and close them and check any change in climb rate. This meshes with what you're saying in a way -- it seems to me when I close my rad the speed doesn't change but by climb rate increases. Obviously, when I trim accordingly to keep the climb rate where I want it, the speed will increase.
However.......we've had a couple of beta patches plus the most recent retail patch, so I could be dead wrong on my observation above.
I have noticed the canopy open/closed has no effect on drag/speed. I tend to fly canopy open now for
1) better visibility -- especially in the Hurri
2) you can hear the DB601 supercharger whine directly behind you as a 109 is lining you up!
