My friend just sold me a 350 4 bolt mains block for $40 bucks. It's in kind of rough shape. It has rust, nothing looks rotting. But my friend said to have it hot tanked and machined. Now with that I'm guessing hot tanking will get rid of all the debris from the block and maybe take away the rust as well or would that be with the machining process? And other tips on getting this block prepped and ready for me to start getting parts for it, would be appreciated

Hot taking will get rid of the scale and carbon and crud and paint that might be sticking to it right now. If there's rust or wear in the cylinder walls, it'll need to be bored. If there's rust or wear on the deck surface, it'll need to be decked. If there's rust or wear in the bearing saddles or main caps, it'll need to be align honed or bored. If there are any cracks, it'll need to be thrown in the trash.

Haha I hear ya. So I should probably get it magnafluxed first to make sure it doesn't have any cracks?

You could. A lot of cracks will show up as a soda line after tanking.

Ahh I see. Hmm well I'll have to check around my area to see who does hot tanking and maybe a mag flux. Thanks Apeiron I appreciate the help

Any automotive machine shop should have a tank. Equipment to magnaflux something as large as a block is pretty expensive and harder to find, but there are other ways to test for cracks, like dye penetrant testing. If you're on a budget you might think about skipping that and take your chances with just a visual inspection.

Now you're talking XD haha well I'm going to look over it and see if I can find anything, hopefully.

The tanking part you'll still want to do, and you'll want the shop to measure the block to see how much machining it might need.

alright, hmm well I'm getting my check tomorrow so I'll see prices on tanking it and seeing how much machining it will need, and or to bore it out :P