
Originally Posted by
rjudgey
you can allways do the head first then do the block lster, but probably just bst to check it's flat, check the wear on the valve guides, just strip and clean up real good, then re-assemble with new oil on parts, also replace vavle stem seals too and any other gaskets that are on the head, also when you do put the head back on the head bolts should be lightly oiled if not you wont get correct torque readings. And the head bolts are fine to be re-used i've re-used a new set about 5 times and not had one snap, the A20A4 bolts are best as they have a even thicker shaft than the A1 and BT series bolts which have like a sprial groove running all the way round, all can be re-used just don't abuse them, 50lb ft isn't much pressure just make sure you re-torque after full heat up and cool down or after 500-1000 miles, otherwise the sma ething will happen again, what happens is a small gap occurs after a while because of the head and block expanding when heated up and cooling down, this gradually crushes the head gasket and after 10-15K or more the pressure from the fuel and air igniting starts burning in between the gasket between the cylinders, and after a while it burns it straight out!! The other reason for it to go as well which is more with the case with me, is that you have such a high CR ratio and/or static compression that the extra pressure caused by this just blows the gasket out completely which is why a lot of turbo cars or well tuned High CR N/A motors have to run a solid copper gasket as this is the only type that will withstand the increased pressure produced, i'm using very good quality H/Gasket and they typicaly last 10-15K before they'll blow out inbetween the cylinders, CR ratio is around 9.5:1 but the Static compression is very high as the engine is highly tuned and is able to flow a lot of air and fuel into the chamber. Should step upto Copper but when you have twin Webers it's very easy to change gasket takes about 2 hours when i'm in a rush, it's also handy as it's a good opportunity to check the head for any problems, and to also de-coke the chambers and clean up the ports and valves of any muck!! When i bolt back up a clean head easy gain of 5-10bhp for a few hundred miles untill it gets all coked up again!!
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