Adjustable A-arms

PostPost by: upnorthelan » Mon May 05, 2008 2:18 pm

I'm building an elan for vintage racing and realize every club has different rules. I've modified my front top a-arms to accept a hyme joint inorder to relieve (and adjust) negative camber created by shorter competition springs (as I've seen on Tony Thompson's website). Did 26R's or competition elans have adjustable suspension, or am I doing something unethical if I want to run the car as period correct?
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PostPost by: Dag-Henning » Tue May 06, 2008 6:07 am

Ethics ? - doesn't it all cook down to regulations....... :wink:

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PostPost by: davidholroyd » Tue May 06, 2008 3:45 pm

Dag,

If you look on the 26r parts list on the web site it states 'rose joints' so I assume ajustable suspension is in period and OK. The question mark has always been ajustable spring platforms that I have and I doubt are legal in up to 65 reg championships. I do not think they had them in the day ... please correct me if I am wrong !
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PostPost by: Dag-Henning » Wed May 07, 2008 6:18 am

- no, you are absolutely right. Adjustable spring platforms are not allowed if you are talking FIA App. K periode "F" , ( -65 ) . Neither are rose joints, or other ways of "adjusting" your suspension in an easy way....!
If you also would like to follow the regulation on ground clearance, there is really not much you can do, besides making sure everything is spot on and straight......

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PostPost by: rgh0 » Wed May 07, 2008 7:51 am

Generally you end up with the optimum around 1 to 1.5 degree negative camber if you lower the suspension a little ( around 20 mm) with shorter springs and / or adjustable platforms if allowed. If you then run 60 series tyres you also end up with optimum ground clearance of around 100mm.

If you have a ground clearance regulation that prevents suspension lowering and are also not allowed adjustable rose joints then I would slot the upper arms ball joint bolt holes to enable the upright to be moved in at the top to get the needed negative camber.

cheers
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PostPost by: upnorthelan » Wed May 07, 2008 2:03 pm

Thanks for the advice everyone
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PostPost by: paros » Sun May 25, 2008 11:15 am

Having raced in FIA, albeit in Greece for 4 years, I know rod ends are illegal and also adjustable platforms - last years Greek championship was truncated to allow people to go non adjustable platforms!
However 2 points. I understand that with FIA rally Escorts adjustable platforms are accepted IF the spring remains the same diameter as original.
Second, I have often wondered whether it would be legal to set the car with adjustable platforms to optimum ride height, cambers and corner weights and then weld up the adjusters so it is all non adjustable. Any one got any ideas?
Slotting the top wishbones is exactly the route I went for FIA, and it was perfect and an easy solution. The rear of the car with the typical twisted rear chassis though is a bigger problem, with a need to make 2 special A frames. An example of being original to comply with FIA rules of the period costing more than a sensible modification such as Rod ends!
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PostPost by: Dag-Henning » Mon May 26, 2008 7:51 am

Richard, the Escort is a periode "G" -car, ( 66-71) in which adjustable spring seats are fully legal. The spring diameter is also free, even in "F" . ( 62 - 66 ) .
Furthermore, I think your sollution with welded adjusters, - or calibrated length sleeves, are perfectly OK.
These modification apply of course to "Competition Touring cars" and "competition GT " . If you enter your car as "std." , you must keep it "standard".

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PostPost by: paros » Mon May 26, 2008 8:41 am

Hi Dag

Many thanks for your thoughts, I will dig a bit deeper next time I see the man who does the FIA papers in the UK at my next race at Silverstone. He races a historic car himself so understands the problems, and tends to be at the same races as I compete in.

Best wishes
Richard
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PostPost by: Dag-Henning » Mon May 26, 2008 11:36 am

Richard, are you going to run the Silverstone Classic end of July ? I am flying over to watch, as I understand Lotus is the "mark of honour" this year.

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PostPost by: paros » Mon May 26, 2008 7:38 pm

Hi Dag

No I am not doing the race at the end of June but one in mid June - MG Car Club. I looked at the regulations for my Elan at the Classic event but there was some problem. I think it was my non FIA front brakes and so as I go on holiday on at that time, I chose not to enter.
Oddly enough I have just put back the standard brakes!
Sorry I won't be able to meet up with you at Silverstone - and I hope the weather is better than now in the UK

Richard
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