I have a seized 305. Is there anything I can do to get it unseized and in running condition? I realize this will be costly but I need a spare engine for when my 350 thats in my camaro needs a rebuild.

 

only way i know how to unseize a engine is a rebuild

 

What "seized" it? Was it from overheating, from sitting for many years, took in water? Whatever caused the seize will have a bearing (no pun intended) on how much internal damage there might be.

 

It was sitting in minnesota for about 5 or so years.

 

Pull out all the spark plugs. Spray some PB Blaster in each spark plug hole, working it around to soak the heck out of each cylinder. Let it stew for a coupla-few days. Then try to turn the engine over by hand using a socket and breaker bar. Hopefully you'll be able to break the rings free and get it turning over. No guarantee on the condition of the cylinder walls. You might wind up with an oil burner, you might get lucky.
Here's another thought, it's possible the starter went out and the bendix gear got stuck in the flywheel. That can give you the impression that the engine is seized when it really isn't. I'd actually check the starter first, but soaking the cylinders and working it in still would be a good idea, even if the problem is with the starter.

 

We've never got that engine running or turning over so I doubt it's the starter. Actually it doesn't even have a starter anymore. It's on the 350 thats on the engine now. According to my parents engines that sit a while in minnesota seize up from the moisture so I'm guessing the cylinder walls are pretty rusted.