Compression vs head gasket type

[knighty]

trikes - scrapping the block is obviously going to be painfull - so you might be able to rescue the situation if you have say M12 threads - drill them out and tap to something like M14 or slightly bigger - which will also give greater thread engagement.......also if you are running head bolts - now is probably time to start thinking abour converting to studs and nuts.........whereby the stud is screwed into the block before the head is fitted, and bottoms out in the block and is therefore solid, then the nut clamps down the fitted head......the reason people do this is that bolts are notorious for giving un-even clamping loads on head gaskets in high performance engines - the nuts and studs will more evenly distribute the clamping load on the head gasket - catch my drift

if you go to M14 studs and nuts.....you will need to either drill the head out for M14 clearance.......or......get some studs made with M14 thread one end and M12 the other, with a M12 shank to pass through the standard head - the latter sounds a better option to get rid of the yielded threads in your shagged block

just to warn you - the stud threads MUST be of the rolled variety.......not screw cut on a lathe or with a die.......rolled threads are a must for extra fatigue/cracking resistance........I would suggest you phone ARP and pick their brains regarding whats available off the shelf before you comission expensive custom jobbies

cheers

knighty

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