head gasket has been replaced, checked for splits and warping no leaking of water can be seen in engine bay, however white smoke pours out when engine is revved, not overheating

Was the head skimmed when the head gasket was done? A Compeession test might tell you more.
Dan

no it wasn't skimmed

Not skimming is a bad, bad, idea. Nevertheless, the white smoke may simply be water in the oil (change it!) or in the exhaust.

Compression test will reveal all.

Most important question: "Why did the HG go in the first place?"

Most important thing to do, find the cause and fix that!

Finger is spot on the money there

Also you have to remember that exhausts are hot - when they cool they develop water inside - which steams off when you start the engine again

next - its cold outside - not as cold as its been in the UK, but its full of damp moist cold air, which is sucked into a Bone dry scorching hot engine

Cold air meets Hot air = Steam

ziggy

thanks for all the comments problem appears to be solved, hg blew into no1 cynlinder, think it may have saturated the cat, coupled with the damp weather nothing, not even road sufaces was drying out, nor white smoke at present, appears to have dried out