Building an engine that produces great power starts with proper block preparation. One of the most critical aspects is the finish of the cylinder bores – To maintain ring seal its important that the bores are perfectly round and parallel. A bore gauge can be used to quickly confirm the bore size (which also allows the piston to bore clearance to be confirmed) as well as checking for roundness and taper in the bores. To add a little complexity, many blocks will distort the bores when the cylinder head is installed and torqued down. This can mean that the bores measure perfectly when the block is bare but the bores may measure out of round with the head fitted. The solution is to utilise a torque plate during the machining process to replicate the stressed introduced by the head.
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