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Discussion Starter #1 (Edited)
My truck did not originally have a rear sway bar.
Adding a Beltech sway made a huge improvement in ride-quality and of course handling and stability also.

A few minutes ago I wondered about the possibility of adding a Panhard bar.
I didn't even know off the top of my head if you could have a Panhard with a leaf suspension, but Google found the answer to that easily.

That led me to the Watts linkage setup, which has been around for a very long time and was used years ago when all cars had leaf springs.

The idea is to help stabilize the rear axle and prevent side-to-side motion when the axle begins to bounce around.

Neither a Panhard or Watts linkage is very sophisticated, I'm sure there are many street-rod shops that can fab one up...

If these trucks were not so damned hard to bag or do a coilover I'd be looking in that direction, but it seems a simple Watts might be way more do-able.

http://www.pro-touring.com/threads/89108-Panhard-Rod-on-a-Leaf-Spring-Car

http://en.wikipedia.org/wiki/Watt's_linkage


Just wondering what might yield a better ride from a basic leaf suspension..
If I can get better handling then that'd be OK too.

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With leafs it's only going to help you in a straight line. Once you head into a turn that rear is going to get a bunch of directional forces from the leafs as they fight the links and cause a bunch of bind on the inside tire. It's hard for me to go into detail without writing paragraphs here, but it wouldn't make an improvement in my eye.

I would suggest you look into a 3 link with panhard and coilovers for the best results(the 3rd link is tough to find a place for but I think it's doable), but a 2 link with panhard, trac bar, and coilovers will still be a one up over the leafs and a little easier to fit under the truck. It's really not that expensive if you plan everything out right and make friends with someone who can weld.

Now if you are trying to avoid cutting up your truck and having it down for a while, you can buy a universal sway bar that is bigger than factory with adjustable links and dial it into your driving style. Also removing the factory shocks and buying aftermarket ones with helper coils and adjustable valving and then stagger the mounting of them. You will never get leafs to perform as good as links though, the drivers who run leafs use more horsepower and a lot of balls to beat link cars on the track. They do make you a better driver though.
 

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Discussion Starter #4 (Edited)
With leafs it's only going to help you in a straight line. Once you head into a turn that rear is going to get a bunch of directional forces from the leafs as they fight the links and cause a bunch of bind on the inside tire. It's hard for me to go into detail without writing paragraphs here, but it wouldn't make an improvement in my eye.

I would suggest you look into a 3 link with panhard and coilovers for the best results(the 3rd link is tough to find a place for but I think it's doable), but a 2 link with panhard, trac bar, and coilovers will still be a one up over the leafs and a little easier to fit under the truck. It's really not that expensive if you plan everything out right and make friends with someone who can weld.

Now if you are trying to avoid cutting up your truck and having it down for a while, you can buy a universal sway bar that is bigger than factory with adjustable links and dial it into your driving style. Also removing the factory shocks and buying aftermarket ones with helper coils and adjustable valving and then stagger the mounting of them. You will never get leafs to perform as good as links though, the drivers who run leafs use more horsepower and a lot of balls to beat link cars on the track. They do make you a better driver though.
Hey, thanks for that. You guys are the best.

I'm willing to put a little cash on the table to get even a small improvement in ride + handling.

As I posted, I'm way better off (in the rear) now than when I started in '05..
Now with Beltech leafs (softer), the Beltech rear sway (where there was originally no swaybar from the factory), and to make up for the beltech leafs, Monroe air shocks.

Really, that combination is working pretty well and I could live with it.
I'm only dropped 3+ inches on 65-series tires.
(I would like to go back to at least 60-series next time around though..)

All that's to say, it's my daily and my only vehicle, and I travel constantly for my work, so I gotta have some ride comfort.

At some point I may be able to make arrangements to leave my truck with someone for 1-2 weeks.. If it's a shop that can do something worthwhile.

With the QA1 coilovers up front I'm more than happy there and I'm not gonna try to go bags all around or anything of the sort.

So maybe I'll look for a 2-link coilover (or bags).
I've got a phone number for a custom shop in north Georgia one member here used a few years ago for a full-out bagged setup.
Spoke to the owner by phone about 3 years ago and he was very helpful.
Back then I was still squeamish about cutting my frame, but I think I'm over that.

I'm expecting to be back south soon, maybe I'll see what he'll quote me for a simple rear setup.



Just a little more ride, and any tiny bit of improvement in handling and I'll be happy.
 

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I'd stick with coilovers, just because bags can leave you stranded pretty easily and your not looking for a show truck. Call up a good shock company that you can afford and tell them what you are doing and the weight of your truck and they will hook you up with you good set-up on the valves and springs. I think you could do a 2 link off the factory leaf mounts pretty easily since you are not looking to lay frame like the bagged guys. They also could be incorporated into a 3 link, just the 3rd link for the top of the pumpkin may be a pain. My trucks lifted so it's tough for me to get an idea how much less space you will have above the axle at a 3" drop, the bedfloor and gas tank may be in the way though and cause some issues.

This would be a cakewalk for a shop that normally bags since they don't have to touch the front or make room to lay frame. If you do go through with this eventually, go for a watts link if you do a 2 link. My first choice would be a 3 link and panhard though with the shocks mounted stagger and with a slight angle to fight some of the lateral forces on the axle, and you will essentially have the set-up of most race cars on the road and oval tracks.

It's what was under this so I can vouch for them personally. I had to run Carrera shocks and they were excellent and easy to rebuild.

 

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You can do an offset link up top and still be fine given the power levels and grip he will achieve. I plan to run a torque arm style setup when it comes time. It will take all the power I can throw at it, that's for sure.

I also had a CRAZY, outlandish idea on how to run a bag setup that was fit for all types of driving and racing, but ultimately, in talking to some of the juggernauts in the industry, it simply requires too much time to tune a suspension with air springs and it also adds alot of weight by comparison.
 

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Oh, to add to the discussion, a panhard bar will, in theory, change the position of the axle through the suspension travel, but a well designed suspension system will minimize this movement. I see alot of top end pro touring cars that run panhard bars with 0 issues. They aren't necessarily the best choice though in a vehicle with a great deal of suspension travel such as a bagged truck or prerunner.
 

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Discussion Starter #9
Lot of great advice and insight here...
Thanks guys!
 

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I am in the process of making a panhard setup for my truck. i bought all the stuff
from Speedway Motors, great prices. just need to make a top frame mount to
attach the rod to. it will have 3/4 heim ends and a turn buckle center for a lot of adjustment
so i can center the rear. it sticks out a 1/2" to the pass side.
 

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Discussion Starter #11 (Edited)
Seem that Street Rod Manufacturing has a "universal" Watts kit.

I was looking at their site to find a phone number to ask some questions about my rear disc conversion kit and I stumbled onto this:

Watts Linkage

This one installs in front of the differential housing, not behind.


They're closed until Tuesday, but I plan to call and see what they can tell me about fitting this to my truck. Someone there must have or have access to a 355 since they designed the rear disc kit for it.
 

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Seem that Street Rod Manufacturing has a "universal" Watts kit.

I was looking at their site to find a phone number to ask some questions about my rear disc conversion kit and I stumbled onto this:

Watts Linkage

This one installs in front of the differential housing, not behind.


They're closed until Tuesday, but I plan to call and see what they can tell me about fitting this to my truck. Someone there must have or have access to a 355 since they designed the rear disc kit for it.
That is a good find! I was just texting to a friend that I need to look into a universal watts and adding 1.5" to the lip of my rims to put 295s all the way around. Then it would corner like I want.

:th_woot:
 

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Discussion Starter #13
At that price, I wouldn't care if it made only a very small difference, in either ride-quality or handling (or both).

Any improvement at all would be worth it to me.

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Discussion Starter #14 (Edited)
I spoke today with Skip at Street Rod Manuf. about the Watts linkage kit.
He was helpful and generous with his time to discuss it.

He's never seen the underside of a 355 so he could only offer some general suggestions.
One thing he offered was the possibility to make a plate that attaches to the rear of the dif housing with the rear cover bolts. I had considered that, but I would think that would require tightening the rear cover bolts much more snug which I would imagine would put a lot of stress on the gasket.


Another possibility he mentioned was mounting the linkage to the frame using an add-on cross-member and then connecting the arms of the Watts unit to the leaf springs rather than the differential housing.
He said he has seen that done on other leaf-spring vehicles.
I would never have thought of that.
 

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it sticks out a 1/2" to the pass side.
This pisses me off so bad. My truck looks retarded going down the road looking down the passenger side. Driver side looks mint!
 

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I used to get mad every time i looked in the rear view mirror, it looks really bad when you go around a curve/turn. i am finally going to fix it this year with a panhard rod i am making.
only have to make the one upper frame mount, got every else ready to go.
 

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Discussion Starter #18
This is pretty informative for me..
If I were on the west coast I would go see these guys..
First time I've seen the process start to finish.


 

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Discussion Starter #20 (Edited)
I just spoke with a gentleman there.. Very pleasant and ready to help.
We didn't have a good connection, so we kept it brief.


They have no experience with 355's but they'll be happy to custom-fab a 2-link kit to order..
The buyer would assume all responsibility for engineering it, providing needed dimensions, etc.

He suggested bags (Shockwaves) rather than a coilover, thinking it'd be easier to get adjusted to correct height.

I'm not adverse to bags in the rear..
I would use an industrial pressure-sensor and fab-up an automatic control circuit to maintain the pressure within limits and prevent the bags from being damaged.

There again, I'm not looking to put it into the weeds. With a good setup though I might be ready to drop another half-inch to an inch or so.

Guess you could always keep a spare bag on-board in case of road-damage, yeah?
 
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