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jaybee
07-30-2014, 04:04 AM
My project is a '57 Chevy Handyman wagon. Plan is to be a relatively low buck (like anything in this hobby can be truly "low buck"), mostly street driven car with the odd autocross, and once comfortable with the handling there probably track day it at least once just to see what it'll do. Engine will be 5.3 or 6.0L GM truck engine with close to stock hp. The wagons don't have a lot of front weight bias stock, and this car will come out close to 50/50 with a fiberglass front end.

Front suspension is planned to have disk brakes (can't drive an old car in modern traffic w/o) and updated steering gear. Idler arm bushings will be replaced with bearings to take the mush out of that point. Geometry will be close to stock because doing all new would blow the budget...two inch lowered springs to get the suspension in a more advantageous part of the camber curve, A arms for strength and to get caster compatible with modern tires, adjustable shocks, and sway bars of course.

Now to my question, the rear. I'm going to put a Ford 8.8" rear under it. They're strong enough, Ranger/Explorer rears are plentiful, the right width, and can come with disk brakes. The thing is, these are slightly oddball suspensions because they use a 2" leaf. They use a particular shackle that's more expensive than a Camaro/Nova part (mine have been replaced with cheap, generic "extended shackle" kit) It's a good idea to put in a shock bar because the floor pan can crack where the shocks mount. My initial plan is to use a modified spring, not just dropped but with an extended front on the 2nd leaf, like a Mopar Super Stock spring. Studying the archives shows me some on here did something similar to what I have in mind with some Camaro springs. Oh, and as for getting just the rate? Fuggedaboutit, and obviously changing rates would be difficult and expensive.

As I budget all this out it looks like I could do a triangulated 4 link for a very similar price compared to the leaf spring rear I have in mind. It would need to be triangulated because the gas tank wraps very tightly around the rear end and I don't wish to relocate it. Labor costs aren't an issue because it would be my work, only parts. I'm planning to do a frame crossmember anyway for strength. Obviously spring rates could be changed much cheaper and easier.

Is there something I'm not considering here? What are the pros and cons of these different approaches? I'm not into changing things just to change them.

j-c-c
07-30-2014, 06:00 AM
Sorry if I sidetrack your thread right out of the gate, I have little experience with triangle 4 links, but my son has it on his 5.0 Mustang, and it seems like the handling crowd bends over backwards to dump that suspension, and so many others are trying to install one? I personally with limited knowledge of a triangle 4 link think it is mainly a cost/packaging/space solution, not handling. I would think optimizing the existing leaf solution, with asymmetrical/mopar leafs, proper rates/composites, needed adj shocks, throw in a panhard/watts if possible. maybe even a swayabr if needed, and you would be good to go for best bang for buck, in my eyes

bret
07-30-2014, 06:21 AM
We use the Tri Link format under our cars. They handle well. http://www.ridetech.com/garage/new-48-hour-camaro/

We have a bolt-on parallel 4 link for the tri 5 Chevys that uses a diagonal link for lateral location. We use that format on that car because it seems to fit that particular car better. http://www.ridetech.com/store/1955-1957-chevy-airbar.html

BUT...if you have some measureing and welding skills, we also have a universal Tri Link that works quite nicely in a wide range of vehicles, including the tri 5 chevy. http://www.ridetech.com/store/weld-in-air4link-triangulated.html

I've driven both styles...hard. I cannot say that one is superior to the other. On paper either will theroetically go into roll bind at about 6 degrees of roll. In reality, if you ever get anywhere close to 6 degrees of roll...you're doing it wrong.

My personal preference...I love the tri link. Simple, easy to install, spreads the lateral load out, no lateral axle migration...and inexpensive. A good set of coilovers or ShockWaves and you are set.

astroracer
07-30-2014, 07:22 AM
I see absolutely no reason to tear up your wagon. It IS a wagon after all and you will never get it to handle like a Corvette. Unless you throw the same kind of money at the front, doing all of this work in the rear is a moot point. As Bret mentioned above, a well maintained leaf can give the same performance as a high dollar 4 link but, you have to have the time and place to get that 4 link tuned in. I suggest doing some due diligence on your leaf springs, poly bushings, add a Sway bar and some good shocks. Maybe lower it a bit with some blocks. That and some good tires and wheels and you will be surprised how well it will handle.
I have a '56 wagon I just picked up and, after I get the leaky 605 power steering box swapped out for the 500, I will look into a rear bar for the car. I think that's all it will need to tighten it up.
Mark

jaybee
07-30-2014, 04:23 PM
Thanks for your feedback, and I see a consensus around my previous intended plan of attack. I only asked because I could see the numbers on the two approaches running pretty close together...if my labor is worth nothing. I'll probably go with my previous plan, then. That would be 3" drop springs modified with the second leaf extended toward the front, poly bushings in the front eyes, stock bushings in the shackles, sway bars front and rear, and a good set of adjustable shocks. Between bar, shocks, and tire pressures I can surely balance the car well enough to put a smile on my face. FWIW I'm not planning a lot of rubber rake on the car. It works against my enjoyment in throwing a car into a corner, I like a car with tire sizes that are closer together, and there's also an exhaust routing issue. Getting really huge tires on these cars requires a "pocket kit" that relocates the springs directly below the frame or even between the frame rails. Either way there's no place to run the exhaust past the fuel tank in that case, and as I've already said I don't wish to move the tank. I'm not afraid of building stuff, but there's already more than enough stuff for me to build without changing things just to say I did.

Oh, and just as a point of trivia it's my understanding one of the unused poly shackle bushings I'll have lying around is just the same internal and external diameter needed for an idler arm bushing. If the bearings are "poor man's power steering" a poly bushing would be "cheap guy's poor man's power steering."

astroracer
07-30-2014, 05:17 PM
That sounds like an excellent plan John! Your observation about getting huge tires on these cars is completely correct and is another reason to simply upgrade the leaf springs. besides a "no tear up" install it's something you can do on a weekend and be back driving the car...
Here is a pic of my '56 Handyman. I went with a bit of a rubber rake. 235/45-17's in front with 265/50-18's out back. :)
https://static1.pt-content.com/images/pt/2014/07/ry3D400-1.jpg

jaybee
07-31-2014, 09:50 AM
Very nice! I'm considering very similar tire sizes myself, though I don't have them at my fingertips.

MonzaRacer
07-31-2014, 10:31 AM
ridetech triangulated 4 link and some RQ coil overs and your set, good ride, good handling for street use and you can upgrade later on or even swap in a swaybar or musclebar later on.

jaybee
07-31-2014, 07:43 PM
Mark, is your Handyman at stock ride height or lowered?

astroracer
08-01-2014, 02:06 AM
Mark, is your Handyman at stock ride height or lowered?
I don't really know John. I was told the front spindles are 2" lowered but haven't verified that. The rear is a 12 bolt and I have no clue if the springs are original or replaced. I plan to figure all of this stuff out once I get her up on the hoist.
Mark