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RX-7 1st Gen Specific (1979-85) RX-7 1979-85 Discussion including performance modifications and technical support sections

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Old 09-27-2009, 02:03 PM   #1
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Default Four linkage?

I think my end goal is to recreate this for the mazda to replace the mazda four link system. This is the setup for a Ford Escort. Designed for rally use obviously. Only question is if a pan hard bar is required.







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Old 09-27-2009, 02:07 PM   #2
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im also hoping i can find premade components to make this a bit easier. Im hoping i can find the attachements to a toyota axle, then perhaps make my own boxes. Then order the linkages at the length i need. Anyone have a good source for such items?
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Old 09-27-2009, 02:34 PM   #3
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There are many aftermarket companies that offer generic 4 link set-ups. Usually includes all the hardware from brackets to heim joints.I would imagine Summit may even have some available. What are your plans for a panhard bar? Or does the toto have a watts style as well?

Here is a pretty nice set-up.

http://gravity-werx.com/index.asp?Pa...TS&Category=31
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Old 09-27-2009, 02:37 PM   #4
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havent decided yet. Will depend on a few factors. In the mean time ill probably see what the rally experts have to say. A panhard bar might be the best.
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Old 09-27-2009, 02:47 PM   #5
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I missed your comment in the OP about the panhard bar.

I will be intrested to see if they use one or not.I can't imagine the rear end flexing side to side being a desirable thing. But I don't rally.
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Old 09-27-2009, 02:51 PM   #6
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there needs to be something to locate the axle side to side.
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Old 09-29-2009, 09:42 PM   #7
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4 link setup definitely needs a panhard.
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Old 09-30-2009, 10:36 AM   #8
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Couldn't you retain the Watts linkage instead? Just wondering...
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Old 09-30-2009, 06:34 PM   #9
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i could but im curious if the panhard would be more sturdy (and simple)
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Old 09-30-2009, 08:07 PM   #10
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Much simpler and more stable. IMO The watts is trying to reinvent the wheel so to speak.
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Old 09-30-2009, 08:30 PM   #11
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Watts is an awesome piece of engineering. I've heard that at extreme angles like autocrossing the watts ends up binding and makes the rear do funky things.

Panhards a sure fire. Make it adjustable, and level to the ground at right height suspension loaded.
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Old 10-01-2009, 11:32 AM   #12
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A properly designed watts linkage is an excellent piece of work. Unfortunately, when Mazda built there's it wasn't perfect. The geometry is not correct on it. But I have heard of people correcting that issue and retaining a properly functioning watts with great success. I'm sure Billy could tell you all about it.

The only problems I'm aware of concerning a panhard is a tendency to break (like ripping right off the frame rail), and when turning one way it will raise the roll center while turning the other direction lowers it.
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Old 10-01-2009, 12:14 PM   #13
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Quote:
Originally Posted by Kentetsu View Post
The only problems I'm aware of concerning a panhard is a tendency to break (like ripping right off the frame rail), and when turning one way it will raise the roll center while turning the other direction lowers it.
That also happens when the rear moves up and down.

A watt's is basically 2 panhards and a proper one will be positioned at the center of the axle. When a panhard is moved to the up and down, the axle moves in a large arc. A watt's corrects this by moving the axle to a between 2 small arcs, almost in a straight line. An animation at Wiki demonstrates this.

Mazda's problem is they wanted to to mount it ahead of the axle, so it's above and to the side. It worked on their RX-3 that beat the Skyline GT-R on the track, so it should work on the street, right? Right? Racing Beat didn't think so, and on their IMSA GTU car instead lowered the watt's center below the axle, still off to the side though.
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Old 10-01-2009, 07:00 PM   #14
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im more concerned about the punishment it can take off road where i need maximum traction but dead relibility. Most in relation to the rotating point of the watts breaking off the axle housing.
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Last edited by Whizbang; 10-01-2009 at 07:04 PM..
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Old 10-11-2009, 07:36 PM   #15
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Ever think of a triangulated 4 link? Where the upper link points are "inboard" on the axle. And mount at a "triangle" to the frame/mounting point. Same on the other side. They will oppose eachother and not let the axle move side to side. Just another idea
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