Well here is a try at it. First you have to measure all the clearances between the cam and the shim holder(bucket). The gaps for intake and exhaust are different. Mark all of these down in order and on a large enough sheet of paper to put these other measurements on it. These measrurements are made with the cams on and tightened down. The head can be on the car or off.
After measuring the gaps and recording them, note the ones that are too close or too wide. The ones with the corrct measurements will of couse be left alone.
Next, take off the camshafts, unless you have the nice tool that allows you to remove the shim with the cam still on the heads. Either way, you have to measure the thickness of the shim. If you clearance on an intake valve is 2 thousandths too wide, then you need to find a shim that is 2 thou, thicker and just the opposite if the clearance is too small.
So you need a micrometer to measure the thickness of the shim, not a vernier caliper, but a real micrometer. You really should have access to a good assortment of shims at this point too. I have collected several from the engine in junkyards and from my own stuff.
After you measure a shim, mark the number down on the shim with a magic marker, that way you will have it for future use on another valve. It is a tedious process but after you do a few, the job get easier. Take your time with this and make sure of your measurements.
It would be best to retake the measurements after relacing the shims and putting the cams back on. A valve that has an initial gap of + or - a thousandths is ok, especially on the wide side. Too close and it can cause the engine to run a bit hotter, too lose and you can hear the light clicking through the valve covers.
Make sure the shims and the buckets are clean when you replace one so you get an accurate measurement. After you do this make sure your cam gears are adjusted properly, but that is another story>
Good luck and let us know how it goes.
Russ
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