I don't disagree with your assessment of 390's, but I thought the '67 GT cam was the same one used in the 428 CJ for a while and had some beef to it?
The 66-67 390 GT/GTA engine is what most people remember the 390 as a turd. With the restrictive "S" manifold, 600 cfm carb, choked exhaust manifolds, limp cam with it's heavy valve train and weak valve springs the stock 390 could barely spin 5K. Not much of a match up against the typical 66 Chevelle 375 hp/396. with its hotter cam, more cfm carb, free flowing exhaust and about the same weight as the Fairlane or Mustang.
My new 1967 Fairlane only the 4 speed 390 GT's with wide ratio 4 speed 2.78 first gear had the 304/324 camshaft. I forget the lift right now but had 94 degree's overlap. Yes, it was the same camshaft that I removed from my friends brand new 1969 SCJ. As they said in My Cousin Vinny they are IDENTICAL LOL in 1969 I worked in a Ford Parts dept and could not buy the Purple stripe camshaft, which was also THE 428 Highway Interceptor hyd stick. The only way I got a new one was to order in a 67 GT 390 short block take it out and drop in a new Pink stripe.
Service cam sold over the parts counter Pink stripe C6OZ-B same as the reg 66-69 390 GT automatic cam and close ratio 4 speeds in Mustangs was 270/290, 46 degree's overlap good upgrade for a stock 390cam. Crane used to and still does grind them both and I think Comp does also all under one part number C60Z-6250-B pick your poison.
