New cylinder head?


7 replies to this topic
  • Treeyz450

Posted February 06, 2016 - 09:13 PM

#1

Might be a dumb question, but can this head be salvaged?
I am assuming not, but just figured I would ask the pros, as this is my first broken valve experience...........ImageUploadedByThumper Talk1454821951.568711.jpg
ImageUploadedByThumper Talk1454821965.183836.jpg I realize the 2nd pic is not of the head

  • grayracer513

Posted February 06, 2016 - 10:26 PM

#2

Engine Dynamaics in California, or Millennium Technologies in the midwest can both fix that.   



  • Treeyz450

Posted February 07, 2016 - 07:12 AM

#3

Engine Dynamaics in California, or Millennium Technologies in the midwest can both fix that.

Thanks.
Now to determine what is cheaper, having my head redone, and new valve train?
Or buying a complete OEM?


  • grayracer513

Posted February 07, 2016 - 07:17 AM

#4

The bare OEM head is $805 new.  You're going to need a complete set of valves for either one, and my guess is that EDCo can fix yours for less than $400 easy. 



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  • Treeyz450

Posted February 07, 2016 - 07:25 AM

#5

Also, I lost 1 intake and bent 1 exhaust valve. What could have caused this?
I am just assuming they were loose because I went a little too long without checking clearances.

  • grayracer513

Posted February 07, 2016 - 07:38 AM

#6

Looks like both exhausts are bent.  "Dropping" the intake valve was the cause of all the other damage.  Usually, this results from running a worn valve for too long.  Once the valve has worn enough to need a shim two sizes (0.10 MM) smaller than the original, the hard coating will have been worn through.  From that point on, if the wear does not progress uniformly, and there's nothing to say it will, it will cause the valve to be twisted slightly at the base of the stem each time it closes, eventually fatiguing it and resulting in a broken stem. 



  • Treeyz450

Posted February 07, 2016 - 08:04 AM

#7

Looks like both exhausts are bent. "Dropping" the intake valve was the cause of all the other damage. Usually, this results from running a worn valve for too long. Once the valve has worn enough to need a shim two sizes (0.10 MM) smaller than the original, the hard coating will have been worn through. From that point on, if the wear does not progress uniformly, and there's nothing to say it will, it will cause the valve to be twisted slightly at the base of the stem each time it closes, eventually fatiguing it and resulting in a broken stem.

Thanks Gray, you are full of good knowledge. Last question...............I usually always go OEM, but would it be beneficial to go with steel valves like kibblewhite?

  • grayracer513

Posted February 07, 2016 - 11:34 AM

#8

SS valves are 40-45% heavier than Ti, so they also need specially made heavier springs to prevent valve float.  Usually, by the time you add those and their custom retainers in, they're more expensive than OEM Ti is.  This is especially true of Kibblewhites, since they build their retainers out of titanium to try to come closer to the lower total weight of the factory valve gear setup. 

 

Besides that, they don't really hold up any better, although most (not all) do have a little bit more "normal" wear cycle.  That is, whereas Ti will last for some years without needing as much as an adjustment, then suddenly "go soft" when the coating finally wears through, SS valves may exhibit slower recession rates once they start to "move". 







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