Lynn also has a good point, building a old set of heads properly is not a real cheap proposition.....although depending on what you have to pay for the old heads it might still be slightly cheaper to do old castings. That will depend on the labor rate of local machine shops and the quality of their work.

I did a pair of "60cc" Power Packs earlier this year. After cleaning, milling, hardened valve seats, new valves (I upgraded from 1.72 to 1.94s) deshrouding the intakes, milling, new springs, retainers and keepers the bill was around $700 not counting the cost of the heads to begin with.

The heads Lynn lists are probably still a bit better as they likely have bigger runners and the combustion may be a lot closer to the claimed volume than the heads I started with. (On the Power Packs I started with, after milling .015 off, the chambers still ran between 62-64 CCs).


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