Erson cam

Is it a hydraulic or a solid? I have an old NOS solid Erson that's close to those specs. I have the cam card and all. I like modern grinds in some cases, but remember, fast rates of lift ain't always the best thing. They usually have some valve train noise because they are slamming the valves open and closed. Not necessarily a good thing for a car that sees 90% or more street time. What ET difference will you see between that good olld reliable old school grind and a modern one that's similar? Maybe 1/10 of a second? Sounds to me like he might know a thing or two.