Ok, I am rebuilding my SR20, and flipped the head over to clean the deck and all my shims fell out in no particular order, FUUUUUUU, now i’ve got to get them back in at the right positions so the rocker arms are level, which is critical. After EXTENSIVE research on this, and looking at all kinds of expensive, custom made tools to do this, I’ve come to the conclusion that I should just take it in to Nissan, get them to do it, and just take it up the ass when they give me the bill.
Are there any shops out there who are capable of doing this as well that might be less expensive than nissan? I can get the engine on the stand brought to them to do this.
I found a youtube video to go by. trying that today, hope it works. I’m gonna add a step by using the SAME matched shim set in each of the 8 positions to get a base reading before doing this, since some of the shims are different thickness and recording the reading I get with the feeler guage. This should hopefully tell me where each of the pairs were originally sitting.
I was also able to figure the matched thicknesses of the pairs so they are all in matching pairs now. Used a micrometer.
UPDATE: This is what I learned so far. Shim height doesn’t really matter that much as long as the shim pairs are matched ± .025, The hydraulics do the job of making sure the valves open to the correct height.
You do need a guage to check that the intake and exhaust valve pairs are the same height. If they aren’t, you have to add this difference to the shim height to figure out if you are over the .025 difference. If you are, then you need a bigger shim to put you back into spec.
Not that hard to do, but time consuming.
I also learned that it’s not really feasible to use the video I posted above. I did everything as above, but the feelers wouldn’t fit.