Yeah, I know. It's on a tractor. But at least it looks like a pre-'65 tractor. At any rate, would this sort of front suspension even be feasible for some kind of a hot-rod application? Cut back on the number of leaves and it could look pretty clean and simple, especially since there's no beam axle involved. No hairpins or wishbone either. Or would it just be "rolling death" at anything over tractor speeds? Can't say I've ever seen one built this way. (photo by member "josrood" at Photography-on-the.net.)
Willys called it "Planadyne" and used it for a long time. No idea how it handles or rides. Maybe somebody will go ahead and build one to see......
Smokey Yunick had a suspension setup like that at Indy one year. The driver sat in a sidepod on the left side of the car.
Best image I could find in a brief search. Look at the front suspension. The upper arms are a leaf spring
I've seen at least a couple similar shots of of Smokey's Indy side- car before. But I'm sure I must have just glanced at those upper arms and ***umed they were some kind of a solid link rather than a spring. So apparently this type of suspension, in the right hands at least, can work effectively at well above "tractor speeds"!
If you add brakes, you would need some sort of link setup to keep the springs from twisting while braking. The Alvis above solved the problem by having four sets of springs in an “A” shape for triangulation. The tractor in the OPs picture has no brakes, so there would be no twist or wrap on the spindle.
The Indy car appears to have some sort of modified "A" frame lower control arms with the upper being the leaf springs. The twisting effect brakes would have on a top and bottom leaf spring suspension would be the biggest problem to solve. I would think a pair of leafs, one upper and one lower with just a center mounting position would really effect braking. That Avis had 4 leaf springs per side, two for the upper and two for the lower. Probably a lot of work just to be different.
None of the examples posted match the OP's request. The Willys Planadyne IFS (and the Studebaker Planar IFS that proceded it) use a transverse leaf at the bottom and an A-Arm above it. The AC Ace (and the Hurst Floor Shift Special) have the spring above the A-Arm. I've seen a few twin transverse leaf suspensions, but all were cyclecars, most of which preceded the four wheel brake era. I suspect that the more sprung weight that it had to carry, the less desirable twin transverse leaf IFS would be. The only pic I could find was the Monaco Nardi Chichibio, a v-twin front-drive[!] hillclimb car: Incidentally, Augusto Monaco also designed the aero-engined Monaco-Trossi grand prix car discussed in the Traditional Images thread:
Found this online , multiple manufacturers and race teams tried it , benefits , maybe maybe not . It was done but not popular .
I had a 51 Willys Jeepster and that had upper A arms and a transverse leaf spring that hooked to the lower spindle, it's very similar to modern Corvettes
The Blood Brothers Cornelian that the Chevrolet brothers raced has always been one of my favorites. Parallel leaf suspension on all 4 corners Pic scabbed from the internet
May well be okay, but seems to put a lot of faith in a leaf spring, I think a forged axle still gets my vote.
Been ruminating over the question since first seeing this thread. I could imagine it working IF the brakes were inboard. This would take a twisting moment off the springs under braking. Likewise at the rear, inboard brakes would do the same. And as the drive would be probably from a frame mounted differential, the drive moment would be removed as well. It's probably not the most efficient use of steel for a suspension setup, but it could work.
That sure looks pretty beefy, but it also starts looking kind of "tractor-y" again. I'm beginning to wonder if a leaf and upper A-arm combo might be the way to go. Would adding a wishbone or some hairpins be enough to allow using more conventional outboard brakes? Also, that oval-shaped tubular frame looks pretty smooth. Any idea what this ch***is was originally under?
It'd act like equal-length, parallel control arms — which act much like leading or trailing arms, i.e. roll centre on the ground and zero camber recovery.
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