Can anyone point me to a good reference for designing and building a diy three-link rear suspension with a Panhard rod? The project is a '64 F100 with a Crown Vic swap and coilovers in the front. I'd like to eliminate the leaf springs in the rear and fabricate a three-link with coilovers and a Panhard rod in the rear. The rear axle is the 8.8 from the Crown Vic. The truck will be a daily driver and occasional Auto-X vehicle.
It's been a long time since I've read the Carrol Smith books but the suspension one is where you want to start. I'm also pretty sure Detroit speed or ride tech has an application for that. You might want to look at their designs for ideas too.
The hard part is making room for the third link since most vehicles have a floor right there. Since you are working with a truck then you have a BIT more leeway in this respect 
You can't go wrong with making the lower links as long as possible (24" good, more is better, less is okay but more compromised) and parallel to the ground at ride height, and the third link about 80% as long and angled down at the front slightly. 3/4" swedge tubes minimum, strongly recommend bucking up for Johnny Joints as they cost only a little bit more than rod ends but last way, way longer.
Panhard a little lower than axle centerline and parallel to the ground, and this is something you may want to play with height wise to balance handling with respect to the front of the car.
I know nothing about trying to weld brackets to the center section of an 8.8. The three links I have done were all on banjo type rearends where I was welding to stamped steel. That said, a 3 link puts weird stresses on the axle housing and a back brace is a good idea. I split one rearend open up the back like cracking an egg.
An S197 Mustang axle seems like the easy button.
In reply to tester (Forum Supporter) :
The super easy button is a rearend from a 3rd/4th gen Camaro, but then after doing several 3 links I am biased toward torque arms
Unless the upper and lower arms are exactly the same length, a one-wheel bump causes the axle tube on that side to rotate, while the other end tries to stay in place. Unless at least one bearing/bushing is rubber/compliant, the differing-length arm setup treats the axle tube as a really big and stiff anti-roll bar. Case in point, my brother had such a setup at the back of his Mazda RX-2 (3?), and when we jacked up one rear tire, it only raised about 1" before the entire side of the car lifted. It was binding because the arms were of different lengths and using rod-ends.
Wouldn't it be simpler to use the late model Vic axle with the parallel bars and horizontal Watts-Link?
In reply to kb58 :
I think you are thinking of something else. I can articulate my 3 link with finger pressure, no binding. The 3 link's advantage is that it is impossible for it to bind, up to the point that the attaching joints lock up at the end of their articulation.
In response to the poster that mentioned Johnny joints, you could also use something like metalcloak's duraflex joints. They sell the forged ends with bushings as an assembly for builders. They would be a much more street friendly alternative, quieter, more durable, and have a huge range of misalignment.
In reply to Pete. (l33t FS) :
Have you done a 3 link on your FB? I'm looking for someone competent to do mine so I can run the car low but have articulation and suspension travel.
Check the pro-touring sites like Lateral-G and Pro-Touring.com. There are many builds of this type, and there is for sure an old F100 build on Lat-G (use search) that has this--I think it used a late-model (non-S550) Mustang setup in the rear. Aim for an offset upper link.
Secondarily, full dropouts for independent S550 rear ends are not that badly priced--a few have spliced these into pickup frames. Independent is always better.
Edit: There also used to be Corner-Carvers.com, which was full of suspension craziness, but I don't know if it still exists . . .
Why a panhard bar? Why not go watts-link if you are designing one from scratch? Its only a bit more complex.
It is hard to get a Watts link very low, Panhards are pretty easy. This is why people get rid of the Watts link on RX-7s and install Panhards.
dannyp84 said:In reply to Pete. (l33t FS) :
Have you done a 3 link on your FB? I'm looking for someone competent to do mine so I can run the car low but have articulation and suspension travel.
Yes, did it in '10 or so, and did my previous car in '06ish. In '18ish I transferred the setup to a Ford 9" which required a lot of hackery to the Watts to clear the pumpkin, not helped by moving the center pivot 40mm down to axle centerline.
9" move-over actually starts on the first page of my GRM projects thread but all the early photos are on Photoberkit and for some reason are not always visible.
I would not call myself competent but the current iteration has not broken. It is very biased to suspension travel as a priority over everything else. Whole car may be for sale.
In reply to Pete. (l33t FS) :
I think you are confusing modifying an existing 3 link with designing a system from scratch. As long as the pivot point of the watts link on the frame side is adjustable to start with its not an issue. My(aftermarket) 3-link kit as an example:
Hard to see here but the truss frame that holds the watts link has vertical adjustability through a series of holes of about 6" or so which can bet set for a pretty wide variety of ride heights. A panhard bar is pretty good...but a watts link is still better.
Wicked93gs said:In reply to Pete. (l33t FS) :
I think you are confusing modifying an existing 3 link with designing a system from scratch. As long as the pivot point of the watts link on the frame side is adjustable to start with its not an issue. My(aftermarket) 3-link kit as an example:
Hard to see here but the truss frame that holds the watts link has vertical adjustability through a series of holes of about 6" or so which can bet set for a pretty wide variety of ride heights. A panhard bar is pretty good...but a watts link is still better.
The Watts has theoretical benefits but over the 6" or so of suspension travel, they both move side to side about the same. And the Panhard can be placed as low as you want it, a Watts will always be compromised. Most Panhard installations I have seen mount the bar about the same height as the lower link mounts. You can't get a Watts roll center that low without running the unit under the axle, with one link ahead and one link behind.
Mazda only used it because they could make the car shorter/could run a larger fuel tank. Racers throw it away if rules allow, just like they throw away the stock 4 link that was compromised so the cars could have a back seat.
now, Mumford links on the other hand.... 
Thank you everyone for your input, you have given me a lot to look up and research. I'm not locked into a Panhard rod, a Watts link might be the best way to go. The nice thing with the truck is 1. Much more room for the setup and 2. The bed is off so it will be easier to work on.
I'm very inexperienced in this, so the more basic your recommendations the better.
I've thought about getting a pullout IRS from a Mustang. This has been done several times and their are several builds to copy, but I've already got the 8.8 and I think a DIY three-link has to be a cheaper alternative that will give me all the performance I'll need.
Mumford!
In reply to mightymike :
One of the coolest swaps I'd seen was a complete MN10 (MN12? I always get it wrong) rearend swap into a '55 Chevy pickup. It literally was just four pieces of steel for the subframe, two plates for the springs, and two shock mounts. Plugged in with an adaptor U joint on the driveshaft and he had the hubs and rotors redrilled to Chevy 5 lug. (He already had a Mustang II front suspension with the Chevy pattern rotors from whatever application)
He made it look like a complete bolt in, because after making the simple brackets, it WAS.
Don't know how it handled because it was just a lowered street rod, but the cool factor was outasite. He did say it rode a ton better...
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