Adj. Rockers // PICS & ????
The number of threads showing" is n't going to be a deffinate between all engines or even all valves for that matter. You need to make sure that your rocker arm geometry is right first, it needs to be just to the intake side of the valve center (just slightly)on your base circle and roll towards the exhaust side, if it gets to close to either side of the vavle, you've got bent valves!