Do all the BBC 572 cu. in. engines use a standard size impeller?......won't be removing the shrink wrap for a couple
of weeks and wanted to order new impellers before the old ones are out to compare.....also, what would be a good
quality impeller to buy?

The engine really has nothing to what sea pump is on it.

If its a standard Merc Bravo sea pump, they are all basically the same. The housing may vary, but they are interchangeable.
http://www.go2marine.com/search.do?a...ater+pump+kits

You'd be better off to just wait and see exactly what you have.

Thanks Griff......I tend to be impatient, but seeing what I have in my hand would be best......are run dry impellers best to use?

OEM Merc impellers are the best. Merc did a test years ago even against the blue Globe impellers. Merc Impellers had the best flow numbers.

i tried the blue impellors years ago and did not like them.they don,t move water like the stock merc ones.