Is this just a drill press or a milling machine you're using on the valves? If it's a drill press how do you plan on maintaining the concentricity of the valve? Just curious, not flaming you or anything.LexKyB13 said:for the port matching, i'm using a die grinder and an assortment of various size and shaped metal cutting tools. for the valve's, i'm using an automated drill press for precise cutting (i found one at an auction for 50 bux, the best investment i've ever made!!!) this maching is also used for doing a 30 degree back cut on the valves themselves. seriously though, if you can get a stock head from a 95-newer ga for a decent price (i got mine from mauibluebird for free, the whole engine actually. he just wanted it gone) just mess around with it, the worst you can do is improve flow just a little, if not tremendously. its not hard to do yourself. study the sentra.net tech section on engines, there are many pictures and descriptions that will help oh so much, thanks to mike kojima.