Rough then smooth as

[rapier]

Can anyone give me a clue as to how my 3.5 v8 carbie engine can run smooth as the day it was born one minute and then sound like its running on 4 or 5 cylinders the next, engine is factory standard, has electronic points module thing that i have changed, new plugs, new leads, fresh fuel,praying, witchcraft etc,any clues what to do next greatly appreciated. Does the same whether engine hot or cold thanks

[wizzid]

If you have no luck sorting the problem, you could try Gareth 0415153887.
He is a Jaguar Land Rover mechanic located at Lachlan. He overhauled the carbys and sorted the rough running on my County.