WRT RAF Mixture settings there are multiple issues. Here are the bugs, how it should work. Stick with me here its a tad confusing
In Ver 1.08 the link between the throttle and the mixture lever in that when the throttle is closed it brings the mixture lever back is now correct this is how it was in both the Hurri and the Spits. IRL this means AUTO RICH.
However the Mixture strength going to the engine is operating in reverse in all Hurris and Spits in CLOD at present.
The Correct setup in real life is:
Mixture lever Back Mixture is AUTO RICH
Mixture Lever Forward Mixture is AUTO LEAN
There were only 2 positions Forward or Back
In Both AUTO RICH or AUTO LEAN compensation for altitude is automatic.
The only real difference between AUTO RICH and AUTO LEAN is each is running a slightly different mixture strength schedule. One suitable for General and all power settings (AUTO RICH) and the other for range/endurance flying at low power settings (AUTO LEAN)
You only really need to run AUTO LEAN if you are really trying to minimise fuel consumption. Anytime you are running AUTO LEAN there are max boost limitations to be adhered to or engine damage will result. (+2.25Lbs Merlin II and III and +4Lbs Merlin XII). Max power and or Boost Cutout operation at 12LBS must have Mixture in AUTO RICH.
VER1.08 IN COD MIXTURE BUGS
MIXTURE LEVER BACK is giving LEAN MIXTURE
WRONG
MIXTURE LEVER FORWARD is Giving RICH MIXTURE
WRONG
Lever has infinite movement
WRONG it should be 2 position only.
MIXTURE LEVER is not working in any AUTO function since passing around 12,000ft you need to select LEAN to get smooth operation. This is
WRONG as AUTO RICH should automatically compensate for altitude.
VER1.08 Workarounds
You will get better cooling using RICH MIXTURE .. it helps on the climb in the Spit IIA especially (though its still out of wack). On take off once full throttle is selected push the mixture lever fully forward to the RICH (WRONG POSITION IN VER 1.08 ) Passing around 12,000ft you will start to get rough engine operation so pull the lever back to the LEAN (WRONG POSITION IN VER 1.08 ) If Activating BOOST CUT OUT you must be in RICH so push the lever forward (WRONG POSITION IN VER1.08 )to RICH .... if you don't you will get rough running and engine damage.
HOW IT SHOULD BE USED IRL
In Reality all you really need to do is just leave the Mixture in the rear position in AUTO RICH and forget about it. You then have Automatic Altitude compensation, No BOOST limitation restrictions, no issues with the throttle moving the mixture lever just go fly.
All of this has been communicated to the Devs ... we now wait for the fix.