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I was quoted $2,700 for cam, springs, push rods, fitting and tune at a place known to be a little more expensive because of their quality of work. They said if I supply my own parts they just take the value off the total. When the AUD$ was good you could get a Comp cam for not much more than $400 and then springs (because they're included in his eBay sale for $120). Anyway, it might be $500-600 more but you'll gain around 50rwkw rather than around 20rwkw.