3 link rear suspension

[parsonsj]

Hey Mark! Sorry I had the genesis of your 3 link wrong.

My thinking is the same as yours. The only real reason to go to a 3 link is to go all out on a road racing course. And if you're gonna do that, then you need the right seats, harness, and cage. A back seat can be worked into the equation, but it necessarily should be a secondary consideration.



jp

[parsonsj]

lateral dynamics is like 2 feet long...

As is mine.

jp

[Mean 69]

My thinking is the same as yours. The only real reason to go to a 3 link is to go all out on a road racing course.

Well, yes, and no. As you know now, the 3-Link setup (again, assuming it's done correctly) is just as much at home on the street, or any environment for that matter. Ride quality is terrific, looks killer, the only real downside is installation, and in relative terms, cost (and I stress relative, when you consider all factors, it's very competitive).

Yes, the upper link on our setup is very long, and there's a very good reason for that. And yes, the upper link on the late Mustangs is very, very short. And there's a reason for that too, but it's not performance oriented. The engineers that designed this 3-Link (i.e. 05 Mustang setup) did so on an incredibly short schedule, with virtually no liberty at all to develop it as well as their capabilities would have allowed. Why? Because in Ford's infinite wisdom, they decided VERY late into the car's development, that using the IRS that they HAD been developing for the car would have been too expensive for production, and would have eaten into margins. They gave the engineers almost no time, and wouldn't allow them to delve into the already finalized body/packaging envelope. And that is a true story, not self serving, and the design has issues. So much so, in fact, that a popular late model Mustang aftermarket suspension company has actually adapted a torque arm setup instead of using the 3-Link, which speaks volumes to not only the design approach (i.e. 3-Link versus Torque Arm), but more importantly to the design execution.

M

[marty69212]

thanks , thats what i wanted to know

[parsonsj]

the 3-Link setup (again, assuming it's done correctly) is just as much at home on the street, or any environment for that matter. Ride quality is terrific, looks killer, the only real downside is installation, and in relative terms, cost (and I stress relative, when you consider all factors, it's very competitive).

Yes, I sure can't argue with that. I completely agree. I was approaching the issue from a different POV: if you already have a working rear suspension, then the only good reason to need the 3 link's kinematics is for real road racing. Most existing OEM designs are fine for street use.

If, for whatever reason, one decides to replace the rear suspension, then the 3 link ought to be on the top of their list of candidates.

jp

[novanutcase]

Marty,

I'm probably the least knowlegeable person on this subject but what I will tell you is that if your going to be beating the snot out of the car, using it to transport your kids is not a good idea. It sounds like you are trying to setup a hybrid and, ultimately, I think you'll not be satisfied with either setup you do in the end. The car won't perform to your satisfaction and transporting your kids will not be very comfortable. I think you need to decide either one or the other!

John

[marty69212]

dont get me wrong.. im no pro racer or anything.. but i want to get in turn the key and go wherever i want, race a day and drive home !!!

[Damn True]

One thing to consider. If you are planning on tracking the car you really ought to have harnesses. If you run harnesses you really ought to mount them correctly. To mount them correctly you need a harness bar. If you have a harness bar the back seat is pretty much off-limits to anyone you care about.

[parsonsj]

One other neat thing about a 3 link is that it also works for drag racing. Adjustable anti-squat is the same thing as adjustable "bite". The only thing to keep in mind is that the single upper link is doing what two links do in a drag racing 4 link. Be sure and size the link bars accordingly.

jp

[Mean 69]

If you are planning on tracking the car you really ought to have harnesses. If you run harnesses you really ought to mount them correctly. To mount them correctly you need a harness bar. If you have a harness bar the back seat is pretty much off-limits to anyone you care about.

Bingo.

To reiterate though, this doesn't mean that a 3-Link and a back seat are mutually exclusive, they aren't necessarily.
M

[Damn True]

Absolutely right. If somone planned only to auto-x the car a harness setup would not be as big of a deal. Though it would help keep you in the seat better which enhances the drivers ability to like.....drive. But on the track one must consider the very real possibility of wadding the thing up and prepare for that.

[zuess4u]

But,

If anyone gets time check out www.jimfays2.com he has designed a nice Watts link that works well, and has been race tested.

Currently Jim Fay and Marcus from www.scandc.com are working on a package for A bodies as well.

Take a look at Jims product....I think youll be suprised, good guy to deal with quality product.

If you call him let him know Bob halt from Phoenix refered you, he may hang up on you...lol

[olds87]

The link you have for Jim Fay dose not work. Here is the correct address http://fays2.net/

[marty69212]

i just ran acrosss this !! check out www.gmachineracing.com ! thats almost exactly what i want only with a watts link and for a camaro!!! does or can anyone make this !!!

[James OLC]

...and pass along a couple of opinions (and facts) based upon my experiences with the LD 3-Link and what you have described as bing your intended use for your car.

I totally respect your desire to have a street legal car that has the ability to be at home on any race track on any given Saturday and I think that a majority of the members on this forum share that desire to some extent or another. That you are looking at retrofitting a 3-link into your car suggests that your desire is for more than having the ability to take your car to the track, you want to be ... competitive (?) ...faster than the other guy (?) ...able to put down some impressive lap times (?) over and above what (you perceive) you can achieve with a modified leaf spring set up. That is great. The issue that I see, however, is that you want all that and the ability to throw your kids in the back seat and go for ice cream when you are done. While the two things are not entirely mutually exclusive, they (at the very least) may require some compromise from both sides.

If it is an absolute requirement that your kids are able to ride in the back seat of your Camaro then the trackability (?) of your can has to suffer. Not because of the packaging of the LD 3-link but because of the other things that you will not be able to incorporate in your car for the track. As has been pointed out, the LD 3-link in no way compromises the ability to have a back seat. In fact when I was mocking my back seat up I found that a near stock mid-80's camaro back seat fit nearly perfectly and required only a bit of modication to fit. The compromise is with the roll bar or roll cage which certainly reduces the usefulness and safety of the rear seat. Even with a removably harness bar (if you go that route) the rear down tubes encroach more on the rear seat than the LD 3-link.

From a performance point of view I am confident that you would be happier with a modified leaf spring set up (see David P. or Carl C. as examples) than with a poorly designed 3-link that sacrifices geometry for packaging. The LD 3-link encroaches on the interior because the suspesion was designed first and foremost to work.

Anyway, take that for what it is worth. I hope that I did not come off like I was posting on cc.com, I just wanted to provide some food for thought. The problem with compromise is that once you have done, you always think "what if".

Just my 2 bits.

[James OLC]

A couple of pics of the cage in the OLC Camaro and how it ties to the LD 3-link:

[marty69212]

so what about www.gmachineracing.com /????????

[James OLC]

If you go back to the last time you asked about 3-links (thread: https://www.pro-touring.com/forum/sh...ad.php?t=30180) Jason from g-machine addresses the Mustang upper link that you are refering to. Jason would probably be the best person to talk to about this so maybe an email or pm is in order. There is are several threads on other boards regarding that upper link so finding more information shouldn't be difficult.

[jason@gmachine]

hello guys, how is everyone?

I think this is the upper link you guys are talking about. I fabricated it, and Louie was the designer. It is made with 3/6" 4130 for the sides and 1/8" 4130 for the top and bottom. The receivers are 4140 Light Racing pinch units that have the highest strength rating in the industry (if you dont believe me then check out lightracing.com). Then we used our Chromoly Heims with the liner to top it off.

Here are some shots of the link.






You can call us at the shop anytime if you have any questions, we always make time to answer any question about any of our products.

Jason

[1971novaSS]

Yes John, but you also made your own floor pans and have a custom rear seat.

Andrew

It is possible to keep a stock rear seat with modification to the floor pans and tranny tunnel. I did it to my nova. But you will have to Modify the metal seat frame work.

I also fit in a mini-tub as well while keeping the stock seat.

If you need some pics/specs then let me know.