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Old 05-27-2016, 01:36 PM   #1
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Default What do do about large valve lash gap?

Hey everyone, I have been setting the valve lash on my rebuilt 2001 VVT cylinder head these last few days and I've run into an issue. I needed new valves on the intake side, and now the gap is comparatively huge to the exhaust side. The shims needed on the exhaust side ranged from .124" to 132" max to be on spec. On the intake side, I need shims between .149" - .155" (~3.88mm) to be in spec. The problem is nobody makes 27mm shims that thick other than custom orders. I do not have the time to wait weeks for custom shims to get in. Does anybody know what I could do? The best I can think of is to go buy some thin washers to put under the shims, and have the shins machined down to the sizes I need.
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Old 05-27-2016, 02:23 PM   #2
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Your machinist should have set the valve height during assembly as measured from the valve spring seat to the tip of the valve. This spec allows you to use factory-range shims. Your valve seats were cut too high, which isn't letting the valve sit at the correct height in the head. Take the cylinder head back to your machinist and ask him to fix his mistake.
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Old 05-27-2016, 08:01 PM   #3
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Thank you Savington, you're the bomb! I'm heading to the machinist tomorrow and I'll see what he says.
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