Engine tuning is difficult to describe in words.

IMHO you MUST find a club and get their engine expert to check out your engine. It should not be necessary to join the club.

N.B. in most cases the engine expert is the guy who flies a lot and his engines start and run without continual adjustment. It is NOT the guy who is NOT FLYING AND FIDDLING WITH HIS ENGINE.

If you are anywhere near Luton PM me.