Adjustable timing gear

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m_jermyn
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Post Sat Jun 26, 2010 3:57 pm

How much is safe to take of the block face and bottom of the cylinder head before you need adjustable cam/timing gear?

I have 7 thou removed of the top of the block and a reface of the head.... Will I need the adjustable timing gear?

Mike
m_jermyn
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Post Sun Jun 27, 2010 8:49 am

Anyone?
Simon13
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Post Sun Jun 27, 2010 10:08 am

best way to check is to stick some plasicine to the valves and bolt it all together with the old gasket and turn it over by hand, unbolt and see how close the contact is.

My guess with a standard cam? is there will be no problem. a human hair is 4 thou roughly.
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bilun777
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Post Sun Jun 27, 2010 10:27 am

ditto: For comparison I have a scrap head that was extremely over skimmed ,at least 1mm . It apparently ran O.K. according to the previous owner.On inspection the squish bands on top of the pistons where touching the head![He thought the noise was noisey tappets]. There was no sign of the pistons touching the valves though. I'd check as Simon says. :D
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m_jermyn
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Post Sun Jun 27, 2010 11:14 am

Thanks guys very helpful...

So 10thou is not enough to worry about but it is best to check with the plasticine, only problem is I no longer have the old head gasket as it tore to shreds when I removed the head.

Any suggestions or should I get another head gasket to double check everything?

Also I assume when screwing the head down for this check I should use the old head bolts correct and not waste the new ones?

Mike