How radical can I go without having to change my stock valve train

 

With any bigger cam you will need to check pushrod length, check for the right lifter preload, retainer to guide clearance, valve stem seal clearance. You can run stock rockers but I'd still check clearance in the rocker. Get the matching springs for the cam and put them in at the right installed height and check for coil bind.

 

In general, the cam grinder can advise you of what is the max lift before you have to change springs, etc...but as previously stated, always check even if they say it's ok.........