Alex, I'm sure others can chime in on this for you. To me this is the only drawback in the Ford Engines. The way they use those shims to adjust lash is so medieval. For that reason when I put on my X heads, I went with the Steeda adjustable cup rocker. This way you set them with the adjustable cup, similar to the stud type rockers. No need to screw around with shims and shim kits or shorter pushrods.....PITA!!!
At any rate make sure you use the Crane method of adjustment. It will take a few more revolutions on the crank but it is fail safe. Because it is so much work to get to the upper valve train on these "L" motors, you want to do it right the first time; if you are not 1000% sure of what you are doing, elicit the help of someone else.
Anyway, on the Crane method, say you want to adjust the #1 intake and exhaust valve set: you rotate the crank until the exhaust is just begining to push the lifter up its bore, then adjust the intake valve. Continue rotating the crank in the clockwise direction(as you are looking at the engine) until the intake valve opens all the way then starts down until it is just about all the way down on the cam then adjust the exhaust valve. Continue on until the other 7 are done....
You are right you might need more shims dpending on your conditions, ie gaskest thickness, deck height and installed height of your valve train.
BTW, The Ford manual way is confusing and the Chilton method it absolutely incorrect!
Later
Steve
