I'd go richer than two turns down, personally... My car's just a b20b and I run 2.5ish down in this colder weather we're having. Then again, my car probably doesn't mind being richer than yours as it's tired and whatever else, who knows.

Might try going another 1/4 of a turn on each, just because. I don't think it'll solve your "problem", but it's probably worth doing anyway. On my car, after driving on the highway and then letting the car drop down to idle speed it dips to lower rpm before working its way back up to my idle speed. Sometimes almost dies. Maybe because I'm a little too rich? Who knows. I currently have a synthetic blend of ATF in mine, and I do NOT recommend it. It isn't thick enough when cold to provide the amount of enrichening that non-synthetic would give. In theory anyway. And I seem to be experiencing that in actuality.
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Kyle - 142, 145, and 244! - Oregon Volvo Tuners?