You can get screw in studs with no taper or hex to tighten them and you don't need to machine the bosses they have been around for many years I used them in the early 60s in gas and modified classes a good source for these are "Pioneer" Part # RM-348-16 for small block chevy and other applications. If your not using guide plates they are fine and of very good quality, and without machining the early head, You have much more thread area holding the stud before entering the water jacket cavity! The early head castings sometimes when machined because of the water jacket only left room for a few threads when tapped!!
I forgot there is no taper or hex to interfere with rocker arm movement and more thread for adjustment. Only an alternative for some reading the thread. But at over 6000 rpm you need fully race prepared heads with a very light vave train!!!!
Last edited by painted jester; 01-31-2013 at 03:19 PM.