my search-foo wasn't taking me closer . . . could someone direct me to a source which will explain the inner workings of an early (1940s or '50s) "grand national" back end? i tried a search and was able to find some of the components, but want a cross section to see how (and Why?) the components relate. thanks
A GM style angled, trailing truck arm rear suspension with coil springs and an adjustable panhard bar. Think pickup truck! A 5x5 bolt pattern and full floating axles. Ford 9" diff.
That sounds like the description of a late 1960s or newer NASCAR rear end...truck arm suspension wasn't introduced by Chevy on their pickups until the mid 1960s.
I'd say that they were using what is known as a "floater" or full floating rear axle similar to if not a 3/4 ton rear axle. They ran them on dirt track cars in Central Texas in the 70's because if you broke an axle shaft you wouldn't loose a wheel, you just didn't move under power. Here is an interesting link. The evolution of NASCAR Sprint Cup cars | Official Site Of NASCAR
i know i didn't ask the question very well, but i think this is what i'm looking for! thanks for the link, too.
My understanding of a Grand National rear end is a Ford 9'' with full floating axles and a 5x5 bolt pattern. I remember reading an article in a late 50's/early 60's Hot Rod Magazine showing how Holman-Moody made the modification. Grand National was the previous term for what are now called "cup cars" in NASCAR
don't depend on me to know what i'm asking for! it's the big hubs sticking out of the wheel that have my attention. i thought my self-guided search got me to the GN rear end, but that doesn't mean i'm correct. sorry for any confusion!
The big hub sticking out of the center of the wheel is for a full floating rear axle (floater) commonly found on 3/4 ton and up trucks. That means instead of the axle shaft being supported by a single bearing inside the end of the housing and the axle shaft carrying the vehicle weight, there are two bearings on the outside of the housing supporting the hub and the vehicle weight. The axle shaft only turns the hub and doesn't support any vehicle weight. If you break an axle on a floater, you don't loose a wheel.
Used on GM pickups 1960 thru 1972............ Widely used on Midwestern dirt cars from at least the 1950s, and likely earlier, and modified the spindles to use the rear hubs from the floater on the right front. Good point! Ray
the front used a modified spindle using a floater snout.I see ray stated the info about front must have been contemplating answer while he did so