Hey folks, I'm in the planning phase of a 23 T project my dad and I are FINALLY getting around to build. I'm trying to figure out the best route with the radius rods. I really want to keep it Ford and use split bones in the front for sure. My concern is how safe rear wishbones would be with a high torque motor. Would they twist, break, etc. easier than a set of hairpins. Thanks in advance.
They WILL bend. Search "torque arms" here. that and reinforced bones are a good way to go. I have done this and posted pics in the past
Here's what I did using a 48 wishbone in the rear and if you look up front, you can see the split 48 bones. After talking to @dana barlow and @striper, I took ideas from both. Dana used a 48 front axle and split the bones. He fish plated the back side of the bones where he made his bends. Striper used 48 front bones for his rear axle and while his reinforcement is a lot more elaborate than mine, they both get the job done. Take the time to take a look at both of those guy's cars. Dana's has survived since he built it in 59 and Striper's gets workouts on all kinds of roads in Australia.
The old Ford factory rear radius rods won't support high torque motors...The solid torque tube driveline was designed to control axle twist...I read an old article in Hotrod mag that said don't use stock old rear radius rods...
Well someplace on the HAMB is a pic of the @raven 's roadster at he HAMB drags. he was using beefed bones on the rear. They looked like a rainbow and all they had in front of them was my 355.
The key to using Ford radius rods on the rear is to add an upper bar(s) to make it more like a three/four link or at least an improvised ladder bar setup. As all the previous replies said, the radius rods are not designed or sufficient strength to be used by themselves to prevent the torque reaction when used with any decent performance engine. BY the time you could add additional material to make the Ford radius rods be strong enough, you lose the nice appearance of them. So add an upper bar or two and they remain mostly hidden and you can use the radius rods as the lower bars.
The "Duke of Durham" slides seamless tubing the whole length of the bones... drills holes at the rear to rosette weld, welds the leading ends back on... he has shortened them, added the tubing and used them as lower 4 bars with the uppers inboard of the frame and up out of sight...
i did it once with a cheap project, datsun motor, model T radius rods, open drive rear. only took a few hundred miles to crack both rods exactly in line with the rear U joint
This is kinda what I have in my head to an extent. what do you call the upper support bars?? sorry I don't know the exact terminology.
I think someone had a packaging idea to clear the body. But just because you can join point A to point B doesn't mean the geometry is good. I think the arc of the top and bottom bars will fight each other and the spring.
Not traditional radius rods but beefy and cheap. Rear trailing arms that came off of a junked '99 Land Rover Discovery. $35 at Pick-N-Pull. They'll take pretty much whatever torque you throw at them!
I broke a pair of '36 rear wishbones behind an early Hemi on a roadster pickup. Broke right where the forging meets the wishbone. Repaired the bones and added a third link that mounted to the top of the rearend and a crossmember behind the trans to control rearend twist and problem solved. The stock Ford wishbones were not designed to take any kind of torque, hence the "torque tube".
The problem is also made a lot worse when you split the bones, which are solid mounted to the rearend housing. This creates significant torque when you have one rear tire higher than the other, like a driveway taken at angle. When you split the bones you effectively make the rearend housing a very large anti-roll bar. Since the housing does not twist, the radius rods must take up the distortion; and being mounted solid without rubber bushings means the radius rod itself has to distort and bend (elastically, it hopefully returns back to original shape). Mounting the front ends closer to center of the car will make it less of a problem than spread out.
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