I've looked through this thread and you have an out of control valvetrain. Hope the following helps.
That photo tells me "Why even run an offset lifter in a W2 at all!"
I'm going to share my thoughts on the W2 head itself as it is part of your problem.
The W2 is a great cylinder head and I have used them many times. The massive offset rocker arm carries its own set of problems and in your case creates or exasperates an additional one.
You should be using more spring pressure on the intake in comparison to the exhaust just because of the mass of the rocker and the offset of the arm itself. Just think of the side loading. I have used as much as 140lbs on the seat in a solid flat tappet build and all of the intakes floated (star pattern on valve tips) while none of the exhaust did. Not only are the valves heavier but so are the rocker arms and then add in the weird geometry and side loading forces. It's almost as bad as a Hemi. That big beautiful offset rocker arm needs its own considerations when it comes to set up. Once you use a paired shaft T&D system you will wonder why you didn't do it sooner. The T&D paired shaft system is really the only good answer for any offset rocker system. Oh and if you are running boost you need to calculate the area in square inches that your boost in PSI is acting on and add that to your spring pressure, you might be surprised that you might need 30-40? lbs (just a guess) more spring to control the valve. The offset rocker arm only adds to this problem.
Offset Lifter: The offset lifter comes from Smallblock Chevy Land and in my opinion--CANNOT ever be used in a 59* degree SBM. Why? A SBC can get away with it for much longer because the lifter bore is parallel with the pushrod and cylinder bank. I believe it would "work" in a BBM but have never tried it. I don't like offset lifters even in a SBC but have used them many times in DIRT engines that get rebuilt at least every year.
An offset lifter in a 59* lifter bore is a short term recipe for disaster--that pushrod is ALWAYS trying its best to make that lifter body rotate--It has lots of leverage and I don't care how BIG and BEEFY you make that lifter tie bar it WILL break. If it IS BEEFY enough it will manifest its unhappiness in other valvetrain unhappiness. If you add spring pressure it will stress the tie bar more, wear out your lifter bore, make the side loading on the rocker arm worse and bring you closer much much sooner to catastrophic failure. Think of a diving board as your tie bar and a 600lb morbidly obese guy standing on the end of it. Now think of the 600lb guy lightly bouncing up and down on it his big ugly feet never leaving the board--You should have about that much open spring force-Solid roller right? Now add lash--Yup you got it now that fat guy's feet are leaving the diving board as the diving board momentarily provides enough force to overcome his mass and make him weightless for a moment in time. You only have so many times before the diving board snaps. In short an offset rocker arm AND an offset lifter in a 59* SBM is in my eyes a perfect storm-**** STORM. If you take a look at your picture a normal non-offset lifter is not going to add much more angularity to your pushrod. IME&IMO completely unnecessary.
Related but not really relevant info: The W2 does not need or even perform well because of the big port inlet. The majic is in the deep bowls=tall S.S. and exhaust port design. If I were to do it again--I'd shrink the inlet with the sole purpose of straightening that pushrod as much as I could, and I would move the lifter over about .060"<<(I've done this) It wouldn't impact the almighty (CFM) flow rate at all but it would allow for higher RPM torque production which equals BIG HP.
I know, long winded post but this is my .02 cents take it FWIW. J.Rob
P.S. Just calculated the area of a 2.055" valve and it is 3.317" so 10psi of boost is 33lbs of force trying to open your intake valve when it is trying to close.
