Low CHTs in Winter temps

[Red Mtn flyer]

re-read your post - you're already blocking the oil cooler. Later posts tell it right - try a SMALL plate to partially block inlet air, a la Cessna. Outlet flow is better engineering, but inlet is lots easier.

[Toobuilder]

I attached a simple sheet metal extension on the cowl outlet of the Rocket to throttle the area a little. Flat strip of aluminum and 3 nutplates. easy on, easy off.