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Discussion Starter #1
I messed up the adjusting valve shims when i did my rebuild,
so i went to do it a minute ago,
and found there is zero clearance between all the shims and cams.

There's supposed to be between 0.20 and 0.30 (EX) and 0.25 to 0.35 (IN).
But there is no space whatsoever.
Anybody know why this is (I turned the crank to the right place).

Could it be that the cam bearing caps are on too tight?
The cams are really hard to turn.
 
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They will be extremely hard to turn but I dont know about the specs.
 

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no, its not because the caps are on too tight.

When you had the head rebuilt, they probably machined the valve seat. This, in turn, will make your valve stick up higher, decrease spring pressure, and make your clearance smaller or nonexistant. You need thinner shims.

And i think you need to check your specifications again. The intake clearances are supposed to be .008" and exhaust is at .010". Your specs show the intake requiring more clearance than the exhaust.


If the thinnest shims available (go to a cylinder head shop, not toyota) do not work, then your only other option is a cam regrind. Be careful though, because the extra extension of your valve (because of the valve seat machining) will lead to inadequate spring pressure and cause your keepers and retainer to wear prematurely. Ask me how I know.
 
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Hey that's some clever thinking!

I did get them to machine the valve seats
Thanks alot.
 

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The best way to correct the problem would be to grind the valve stems. Of course this means full disassembly, but that's certainly easier than a cam regrind.
 

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turbotoy said:
The best way to correct the problem would be to grind the valve stems. Of course this means full disassembly, but that's certainly easier than a cam regrind.
I wouldnt say EASIER, but if you are looking for a performance upgrade, it makes the cam regrind fit better and may avoid the requirement for new shims to fill the gap. I found it easier to just send out my camshafts and have them sent back. Some places can do it in a couple of days. If you have your head on the block still, I would try this first.
 
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