If your rocker studs are 1 3/4" from guide plate to top of stud, you might try ones that are 2", or at least estimate if that will help. But before that just assemble with red dry erase marker on tip of valve stem and check the pattern when rotating the assembly. If it is centered and narrow that is what you are looking for.

 

I can't really do the marker test though until I have pushrods. I'd like to have the geometry right and then measure the length I need

 

Have you considered buying an adjustable pushrod? Comp Cams makes them and they are invaluable for determining pushrod length.

 

I have them for both the intake and exhaust. but until the rocker arm is in the right position they won't give useful info.

I'm going to measure what I have for studs tomorrow and see what it would take to get the geometry right. If there's studs that will get me in the ballpark, I'll know it's my solution. If not, I'll know something else is a miss.

 

You only temporarily need the stud longer, just for the time needed to do the procedure.
Put a couple head bolt washers under the stud hex, for the test, as spacers to extend the stud enough you can get a thread started on the polylock.

Otherwise, you'll likely order a rocker stud that ends up too long to lock the poly lock allen screw when it is ready-to-run adjusted.

Just to help you with info...it is common to find a stock length stud is too short for use with the mid-lift method, that video. SBC is the same way, i expect others are too.

 

So... with valve opened .290" and rocker perpendicular to valve you don't have rocker stud threads available?

 

Its not uncommon that you need longer studs than what aftermarket heads comes with.
Do you know the effective lenght on your current studs? I have used 2.100” long studs on several BBC builds or split sets of 2.000/2.100.
Another important thing is that you want the at least the bottom of the trunion on the shank of the stud not the threads.

 

I'm inserting my question, Is 5-1/2 turns enough grip on the rocker studs?
I bought an assembled long block and when double checking my valvetrain we noticed there's only 5-1/2 turns on the nut when tightening to zero lash. I'm referring to the nut that holds the rocker onto the stud, you then tighten the lock with an 7/32 Allen wrench.
(SBC Dart Pro-1 200cc/64 aluminum heads with hydraulic lifters and a roller cam)
Is 5-1/2 turns enough grip on that rocker stud?

 

What springpressure? 5 1/2 turn is little less than you want. 6-7 turns is minimum imo.