Old school suspension upgrade

Technical info not specifically 1st gen RX7 related.
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Old school suspension upgrade

Post by TOOL »

This type of upgrade will work on any model car, and come in at a fraction of the cost of name brands or coilover kits.

In this example, I'll be using an RX2 (cos that's all I've got).

The front and rear suspension is similar to the FB. MacPherson stru up front, live axle in the rear with coils ( not leaf springs like RX3 and RX4), and a panhard rod, not a watts link.

To lower the car, I had custom coils made up to my specification: 30% stiffer plus lowering the car 35mm (or thereabouts).
Now, I'm not sure what RB springs cost landed, but the custom springs cost £45 a corner.

I had them made by a company in Sheffield: http://www.coilsprings.co.uk/lowering.html

Great service. More to ply he point, they got the ride height right. I sent them a front and rear coil to work from and they got it spot on.

Before

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After

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Re: Old school suspension upgrade

Post by TOOL »

The old springs weren't captive at full extension so I had the correct this too

Front springs, old one on the left

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Rear springs, old one on the left

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Re: Old school suspension upgrade

Post by TOOL »

The install

Rears

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Fronts

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Re: Old school suspension upgrade

Post by TOOL »

I've got some KYB shocks in the back. They're good units.

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I've got KONI red adjustables in the front. They're even better.
Ive just had the rebuilt as the nylon washer in the top had disintegrated and was jamming up the valves.

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Re: Old school suspension upgrade

Post by TOOL »

I've replaced all the rubber bushes with urethane so all nice and tight.

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Drilling out the old bushes

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The end result

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Re: Old school suspension upgrade

Post by TOOL »

Fitting Bump steer spacers. They help to keep the control arms level.

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Re: Old school suspension upgrade

Post by KiwiDave »

Interesting stuff there. What's the ride like now on uneven surfaces. Mine's quite crash / bang now but then again, I have no idea how much stiffer the springs are as a percentage over standard.
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Re: Old school suspension upgrade

Post by TOOL »

To be honest, it's been fairly brutal. I'm putting it down to the KONIs jamming up and me having them set on maximum hard.

That should all change now.

The previous pics were from 2010/2011 when I did the first of the work, changing all the bushes and springs.

There's going to be more recent pics and further upgrades shortly. Watch this space.
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Re: Old school suspension upgrade

Post by TOOL »

Fitting caster blocks.

These fit between the front swaybar mounts. They pull the swaybar forward and down, helping prevent diving under braking. RX2s are known to suffer from a lack of caster.

Image

News bushes fitted of course.
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Re: Old school suspension upgrade

Post by TOOL »

The RX2 is fitted with a panhard rod, not a watts link. It's job is to prevent lateral movement of the axle.

When you lower the car beyond a certain point, the panhard link pushes the axle to the left. You need to modify the panhard rod to correct this and centralise the axle again. A good sign of this is the tyres rubbing on the left rear.

The modified panhard rod.

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Fitted in place

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The panhard rod was modified by Andy Robinson of Andy Robinson Racing for £60. Top work from the former European drag racing record holder who builds his own chassis's.

The same principle all pies to a watts link. You can also remove the troublesome watts link and replace it with a panhard rod.
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