appreciate any help , 440 has a smooth idle during warm up , once warmed up , 180 to 190 degrees , after idleing for a while , the motor seems to load up & rev drop slowly 3 to 400 revs from 800 rpm , black /blueish smoke out tail pipes blip the throttle be ok , then it might do it again teo or three times , then next time i go for a run & let it idle , its perfect , carbs recent , new fuel lines & filter new pump & pump push rod , heat cross over blocked off , manual choke , there is no set pattern for doing this , if it dont do it one day , if it does it the next day it will do it two or three times
appreciate any ideas , feed back etc