white smoke on startup and rev up
 

1989 chevy g20 van.. V8,
chevy 350 small block
I am having white smoke on startup and during rev up. I know some is expected on these old engines... how much is expected and what are the possible causes?

Have you checked the oil when i first got my truck -1974 chevy- it blew white smoke on start and rev but after i drained and put some new oil in it, it had no more smoke

NY 2 cents

There is oil in the pistons I'd make sure its not a head gasket if its nothing like that it will stop smoking after its burnt off.

Worn valve guides or stuck oil sweeper rings.