Originally Posted By: OVERK1LL
You could be correct there. I've seen GM use both setups.
Chevy was ball/stud for the most part (I haven't kept up with details of the LS-series, honestly). Oldsmobile and Cadillac used shaft-mounted rockers. Buick too, IIRC.
Chrysler used rocker shafts exclusively up until the "Magnum" series of the 318 and 360, when they switched to a braced stud system adopted from AMC v8s after the companies merged. Well, there was one exception: the ball-stud Hemi. Around 1970, the company considered Hemi-head big-block engines the 440 and 383, but to avoid the complexity of the dual rocker shafts used on the 426 Street Hemi they planned to use Chevy-like ball-stud rockers. A couple of prototypes were built, and I think one still existed in **** Landy's collection at the time of his death anyway. Various reasons were given for the engine never going into production- either ChryCo had already read the tea leaves and knew that the big-block would be extinct in less than 10 years, or work already done on the Street Hemi had shown that it was going to be hard to meet EPA emissions regs scheduled to come rolling in starting in 71. Either way, they made a good call. As much fun as a cheap Hemi big-block would have been, they'd have never gotten a return on investment since the gas crunch was only a couple of years away and smallblocks took over the world.
You could be correct there. I've seen GM use both setups.
Chevy was ball/stud for the most part (I haven't kept up with details of the LS-series, honestly). Oldsmobile and Cadillac used shaft-mounted rockers. Buick too, IIRC.
Chrysler used rocker shafts exclusively up until the "Magnum" series of the 318 and 360, when they switched to a braced stud system adopted from AMC v8s after the companies merged. Well, there was one exception: the ball-stud Hemi. Around 1970, the company considered Hemi-head big-block engines the 440 and 383, but to avoid the complexity of the dual rocker shafts used on the 426 Street Hemi they planned to use Chevy-like ball-stud rockers. A couple of prototypes were built, and I think one still existed in **** Landy's collection at the time of his death anyway. Various reasons were given for the engine never going into production- either ChryCo had already read the tea leaves and knew that the big-block would be extinct in less than 10 years, or work already done on the Street Hemi had shown that it was going to be hard to meet EPA emissions regs scheduled to come rolling in starting in 71. Either way, they made a good call. As much fun as a cheap Hemi big-block would have been, they'd have never gotten a return on investment since the gas crunch was only a couple of years away and smallblocks took over the world.