Valve Clearance Specs

5 replies to this topic
  • Chills

Posted January 04, 2005 - 11:29 AM


Hey Guys,

New to the website, but a definite + in my eyes. I browsed through the forums searching for Valve Clearance Spec on an 01 426 all the way back to the year 2000 posting dates without any luck. My manual is on order, but since I have the engine out of the frame while everything is getting powder coated I wanted to check the valve clearance.

Can someone please post the specs???


  • Satch0922

Posted January 04, 2005 - 12:10 PM


Look here in chapter 3-23 426 Shop manual

  • Chills

Posted January 04, 2005 - 12:28 PM


Thx Satch

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  • Chills

Posted January 04, 2005 - 03:15 PM


OK, checked the Valves and I have a question. The 2 exhaust valves measure .203mm so those are within specs.

On the Intake Valves, the left and middle valve measure .102mm (Within Specs) but the 3rd Valve (On the Right side of the engine looking down) measures .076mm. If I take out .05mm in the clearance on that one it will be .126mm. Granted that it will be within specs, but since that valve will have a different clearance than the other 2, will it make a difference?

  • Satch0922

Posted January 04, 2005 - 06:20 PM


get the shim closest to what the valve chart suggests...then you will be ok. If that is what you have listed and it is within spec, your good.

  • grayracer513

Posted January 05, 2005 - 10:08 AM


Satch is correct; in spec is in spec.

When you're looking at these figures in metric terms, they tend to get exaggerated. The range for the intakes, .10 to .15, is a range of 5 hundredths, which can sound like more than it is if you're used to English measure. In inches, that range is .004-.006. The .024mm difference you will end up with in your intake valves is less than one thousandth of an inch (.00094"). :cry:

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