had a 2.8 car and put a 350 carbbed in it and when I crank it over it starts hard,almost like the battery is dead but it's not,I have a stock 86 350 with 305 416 heads and a mild cam,would the stock starter be enough to turn it over good?

 

if you've got a bunch more compression, it's harder to turn the motor over. A marginal starter could be strained more.
I'd just check all the connections, specifically engine ground, and whatnot, clean 'em up, replace 'em if you want.
Is the starter old?

 

Does it make a horrible grinding noise when it tries to crank?

How much shim is between the starter and the block? Does it get worse, or better, or no change, if you put more shim in it?

Is it a 70s 350 block such as 010 casting, and did you get it for a super good deal along with some improbable story about why the PO took a supposedly running motor out of his car and is selling it?

 

Possible that you have timing to far advanced as well if it is hard to turn over.