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, but I'm just having a regular joe blow machinist do my heads. Before I sent them to machinst, I port matched the intake and intake port to the gasket. There will be no bowl work, just 3 angles on the seat and 2 angles on the face of the valves. The 3 angles on the seat will be 60, 45 and 30 and the 2 angles on the valve face will be 30 BEHIND the 45 (this is the recommended procedure from the Buick Powersource manual, to increase flow). I ordered new valves, from a company called SI valves (1.745 intake and 1.50 exhaust). They are stainless steel swirl polished valves with back cut stems ($11.86/ valve). I'm using Crane keepers and retainer, with a mixture of 0.050 plus and standard keepers and retainers (ordered from SI valves). Valve stem height is within 0.002 of spec. The valve springs are 3927142 GM springs (SBC 1st racing design camshaft spring; 110# @ 1.7 installed height, with a 358#/inch spring rate) and the combination of standard and 0.050 plus keepers and retainers have allowed the machinist to bring valve spring installed height to within 0.002 inch of one another. The 3 angle valve job leaves the seats kind of thin, and the multi angle or 5 angle valve job leaves the seats thinner. This makes the seats more prone to cracking. So I chose a 3 angles max. If your primary goal is racing, then the 5 or multi angle vavle job is the way to go, but IMHO unless you're going to tear down a lot (like lots of racers do), stay with the 3 angles or less on the seat. Sometimes more is not better, for the street. Your machinist can do whatever your requirements are, you just have to communicate the specifics to him/her and be firm in getting what you want (you're the one shelling the dough).
