I had the pleasure of seeing an original 7 at a racing workshop yesterday - unfortunately didn't have my camera so will return next week to take some photo's and investigate further.

I was thinking about the front suspension setup when it suddenly struck me that there was something very peculiar about it.

1 - the lower A-arm seems to terminate in a "bell-crank" with the shock mounted on one end and the upright on the other - I think there is some kind of stop to prevent it going "over-center" but it seems to have significant benefits in full droop allowing a lot more droop than the shock length would normally allow thus allowing more shock movement to be used on bump and hence softer springs.

2 - the above arrangement also gives reducing scrub on bump or roll - the setup has huge scrub at ride height passing well inside the inner wheel edge.

3 - the upper arm is a single arm with the roll bar adding lateral support - looks like a lower cortina or mark 1 Escort arm.

The arrangement puts very little strain on the lower arms and their size is minimal.

I will definitely investigate further - anybody know if I've got the system right or did I misunderstand what was happening.

I don't know what you have seen.

But the Caterham and Donkervoort have still the same (and a little .....)

I don't think it's different
Only the upper arm has the anti-roll bar in the upper arm, making the "A" complete.
The lower strut mounting is lowered to fit.

It sure looks quit nice, but no complicated thinking. Look here:


owners manual series 2,3,4

[Edited on 4/5/07 by t.j.]

The uprights are standard motor company and were found on spitfires and heralds. They have trunnions on the bottom and a stub axle that take rwd escort front end. early one had only one link at the top connected to the anti roll bar.

[Edited on 4-5-07 by mangogrooveworkshop]

OK - Thanks for the feedback - I obviously misunderstood some of it - obviously from the manual that "bell-crank" is fixed not pivoting.

We don't see many catehams in SA so I'm ignorant about them.

I just looked into your site.

If that's your workshop, how do your house look like!

quote:

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Originally posted by t.j.
I just looked into your site.

If that's your workshop, how do your house look like!

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One for you to look at is a Birkin seven. Its an original S3 design that was produced in Pinetown for many years. Its more original than the Caterham since it wasnt changed much under the Aparthied era. If it wasnt broke why change it. The newer Birkin has changes due to kents drying up and saftey regs but very much a seven. The factory was opened by Nigel Mansell and Hazel Chapman in conjunction with the Lotus dealers of SA.

It was this company that took on the Cats lawyers and beat them up. That then paved the way for the replicas to be produced. case of Caterham Car Sales & Coachworks Ltd v Birkin Cars (Pty) Ltd. 1998 (3) SA 938 (SCA).
This case was after the cats beat up Robin hood and Westfield. Last count the lawyers now keep track of 32 replicas. Its a wonder uncle ron never got leaned on.....

It was on the web somewhere if you care to look.
History lesson over chaps

Thanks - another interesting bit of South African kit car history was a local Cobra manufacturer registering the trade mark "Cobra" which had expired in SA.

Ford sued them and lost with costs to them.

When Ford failed to pay I heard they attached the Ford badge - the costs where paid the next day.

I love it when the small guy wins.