its simple on certain levels if your someone who actually designs engines from ground up and work for a company like BMW or honda then it isnt simple. but if you do it sorta as a hobby buying an engine block and head and slapping them together it isnt that complicated.
http://www.turbobygarrett.com/ ... nter/turbo_tech102.html#b
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i didn't mean to gerneralize but it is true to some extent.