Head gasket horror

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ArmandTanzarian
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Well that would explain why I was having so much trouble jetting up the new exhaust and why I spent an hour and a half freezing my nuts off by the side of the road waiting for the AA last night!

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while we're in the barrel.... does this piston look like its coming up too far. With a thick head gasket the squish is around 1mm.

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Meus Lambretta est non infractus. Is est quietus.
davidblythe
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no problem running with negative deck clearance

reason why i dont use head gaskets unless they are 1.8mm thick
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ArmandTanzarian
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What is the recommended squish for a tuned indian barrel? the bloke that did the work said that 1mm was fine.
Meus Lambretta est non infractus. Is est quietus.
davidblythe
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better to pack up with the base gasket to run without the head gasket

as in your case with negative deck clearance you have lowered your exhaust and tfr timings whilst increasing the inlet timing from standard

1 to 1.5mm is fine

normally find the squish increases across the piston as the cylinder head is not machined correctly
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Special X
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1mm is pushing your luck for road use. I'd use a nice thick original style hallite base gasket and set your squish to 1.4/1.5mm fit a good quality gasket to perfectl clean surfaces and preferably lap the mating surface on a mirror or similar flat surface prior to assembly.
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ArmandTanzarian
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I've put in an extra base gasket. It only makes about 0.3mm difference but better safe than sorry.
Meus Lambretta est non infractus. Is est quietus.
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