True but when i was doing bikes it was the same for all cams. they all start as factory cams. Even today cams for a busa are almost all regrinds until you get to the prostock stuff and they use different engines.
Only a few engines in the world have aftermarket cams avilable. Even something as popular as a honda civic has very little cam choice and 99 percent of them are regrinds. To name a few bmw m5 m3 merc amg and many others if you want cams they are going to be smaller than stock. And the valves will need to be setup correctly. Usally just thicker shims or longer vavles.
Just the way its been done since day one. I have even seen them ground at very small shops with no eqipment its a myth that cams can only be one grind. Taking a few thou off the back side give you a much more agressive cam and can be done with simple equipment. Not that I would do this, cause of todays demands but its not uncommon. I know someone right now that has regrind cams in there bike they did in there own garage. Yep its perfect by the way. Amazing work only took 6 oem cams to get one right. LOL
Doing a stock 383 I was always told to use pink rods that have been cleaned smoothed and shot peened to allow for more clearence around the cam. Glad to hear your old but didnt the 400 come out in the 70's and didnt hit the market for years after that since they were never in a real fast car. I think if you had a 400 you didnt want a 383 they only became usable when the cranks got cheap and became drop in replacements. I dont remeber any 383 builds before 1980 or even the late 80's or 90's. If you had a 400 crank a 400 block was the way to go. Now its just cheaper to use a 350 block with the stroker aftermarket cranks.
383 with all factory parts uses a short rod and a long crank with the stock height 350 piston. It is a very bad design and does not last or run that well. At 6K rpm they are grenades. Remember us young guys had a lot of advantage over you old folks we got to learn from your mistakes. <= just for the young guy comments LOL