engine mods?

Is it possible to put LS1 parts on any 350, or can they only be used with LS1 blocks?

i think it depends on what parts. but for most, if not all, NO!

Hmmm.  That sucks.  I'm still trying to figure out why if you can't.  LS1=small block 350.

Look at them side by side and you will see why.

You can use LT-1 parts, the heads are a nice upgrade. I think the only other things you would need are center bolt valve covers (if you dont already have them) and self aligning roller rockers. But the guy that I bought my engine kit from told me that most 305/350's he has seen with lt1 heads have overheating issues so you would have to upgrade the cooling system...

If you are refering to the LT1 2gen sb heads, I don't think will work to well on a 1stgen sb because of the reverse cooling system. But if you are talking about the LT-1 found on the late 60s early 70s, these were bolted to 1st gen engines.