Yes, I can remember the introduction of the sbc in 1955. An interesting note to a hot rodder was the 2bbl non power pack engines had mechanical lifters while the 4bbl PP engines had hydraulic lifters. Maybe this was to limit rpms with valve float since the piston skirts on all 265's and early 283's would break at anything over 5k rpm. We thought we had hit the jackpot with the super light 2bbl mechanical lifters but soon learned stronger valve springs would run the push rod right through a lifter like a tooth pick in a hamburger bun. Till roller cams were introduced we used to bush the lifter bores and use the Ford Y-block mushroom lifter to get away with more radical cams. Upper end oiling had to be fabbed. Later mushroom lifters were offered in factory lifter diameter but one had to spot face the bottom of the lifter bore to give cam lobe clearance. This was for sprint cars so don't know if the drag people ever did this.
