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Okay, sportsfans. As with searching, and searching for confirmed, observed, timed, sanctioned top speeds of 1940-47 senior Buicks and Packards, we've long sought a solid answer to Safe-T-fleX vs. the traditional IFS in Cadillacs, etc., like the 1941-47 Packard Clipper used.

First, i well know the details of Safe-T-fleX, owning a '40 120 for years. We know the postwar R-R/Bentley copied Safe-T-fleX nut for bolt, and as a rear suspension, the postwar W.O. Bentley-designed Lagonda, W.O. long being an open admirer of Packard.

But, perhaps, and let's be brutally honest, no conjecture, perhaps this was simply so R-R and Lagonda would have to pay less in royalties. As i understand, the 1956-on R-R Silver Cloud and concurrent Bentley S-1 didn't use Safe-T-fleX for the same reason it was omitted from the 1941-47 Clippers; the lowered floorpan left no room for Safe-T-fleX's long torque arms.

So, we'd love to see any period SAE papers, technical/trade discussion as to which suspension was better overall, which had the edge.

Please, most of us here gathered are hardcore Packard folk and already sold, so spare us breathless clubbie boosterism. We're among Packard friends, so might let our hair down, relax, and get to the truth. Regardless what that truth be, 'twill not dampen my affection for my '47 Super Clipper in the least.

As Sgt. Joe Friday asked, "Just that facts, ma'am."

Many thanks for any of the above, credible insight, reports, SAE and other engineering trade journal comparisons.

I'm no expert but I think the breakthrough in the Safe T Flex design, was the wide spread mounting points of the control arm, which allowed the use of soft rubber mountings without excess movement at the wheel. Competitive makes used solid bushings mounted close together which controlled the wheel but did not absorb bumps.

Ford copied the Safe T Flex idea in the sixties and achieved a softer smoother ride than their competitors. I think eventually everyone made some version of the same idea. The lower control arm may not have looked exactly the same but it had rubber mounts to absorb bumps, wide spread for stability.

I think the main advantage in absorbing bumps was that the rubber allowed rearward compliance, in other words the wheel could move backwards as well as upwards.

So, if everyone eventually copied it, and it was still giving the best ride of any design 40 years after Packard invented it, I would say the idea had merit.