1965 289 motor,need valve springs that dont require cutting the spring pockets.what springs can i use?very mild cam,just need new springs to go with it.
IIRC, the only time I've cut spring seats were on the early heads for a larger diameter (1.625") spring package for racing. There's a combo tool that goes in the mill which cuts the seat and guide in one operation for the smaller diameter valve stem seal which is needed when running multiple springs.
For near-OEM, all I ever did was machine the guide for the PTFE stem seal and run a stock diameter spring. With most mild-moderate camshafts, there is plenty of spring installed height, and that can be adjusted with easily available longer valves. I prefer to leave the OEM-type heads as untouched as possible, machining-wise, for stability.
IMO, if you're running a 'mild' cam (under .500" gross lift), you'll be fine with a good quality single spring and damper in the OEM diameter. When checking valve to piston clearance, you can check for coil bind clearance. I've never had an issue so doubt you will, but always check. Everything