t.j.
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 posted on 4/2/06 at 06:09 PM |
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roll centre
Hi,
Back from the drawingboard:
I'm drawing my "seven" with tiger-avon front suspension, using the escort MK2 steering-rack and uprights from a Taunus(cortina) MK2.
Wheelbase 2380mm (my lenght is 190cm) front-track 1410mm at rear 1480-1500 mm.
My roll-centre is at front placed at 50 mm,
at the rear at 100 mm.
Is this a good choice or schould it be lower?
The car is for road-use. : I think lowering wil result in to sensitive steering.
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jon_boy
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| posted on 4/2/06 at 06:57 PM |
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To be honest thats only static roll centre and will probably vary with roll/speed etc. those figures sound ok though. considering with a live axle the
rear roll centre is approx at the centre of the diff and therefore i would think somewhat higher than yours.
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britishtrident
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| posted on 4/2/06 at 06:58 PM |
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Sounds about right --
Roll centres are really only a starting point unless you get them miles out or some other aspect of the suspension really far out the car can always
be balanced by stiffness changes or changing the tyre sizes.
Be careful that you don't follow the Tiger Avon layout too closely -- some aspects of the suspension were a bit counter to accepted
Seven/Locost practice.
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t.j.
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| posted on 4/2/06 at 11:17 PM |
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[
Be careful that you don't follow the Tiger Avon layout too closely -- some aspects of the suspension were a bit counter to accepted
Seven/Locost practice.
 What do you mean?
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Mix
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| posted on 5/2/06 at 09:36 AM |
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If you're using the Tiger IRS for inspiration be aware that the wishbones converge towards the uprights giving undesirable camber change in
bump.
Mick
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cymtriks
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| posted on 5/2/06 at 01:20 PM |
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Seven roll centres
Deon Axle Caterham
Front suspension
roll centre height 60mm
Rear suspension
roll centre height 120mm
Experimental Caterham CSR (Independent rear suspension)
Front suspension
roll centre height 30mm
Rear suspension
roll centre height 65mm
Lotus Elise
Front suspension
roll centre height 30mm
Rear suspension
roll centre height 75mm
With a live rear axle the roll centre is not in the centre of the diff, it's where the lateral restraint is. On the Caterham Deon, for example,
the lateral restraint is the lower A arm which connects to a central bracket on the bottom of the Deon tube. That puts the RC well below the diff, at
120mm, as stated above.
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t.j.
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| posted on 5/2/06 at 07:34 PM |
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quote:
Originally posted by Mix
If you're using the Tiger IRS for inspiration be aware that the wishbones converge towards the uprights giving undesirable camber change in
bump.
Mick
Hi,
All my wishbones come to getter in one point at the front. I also made the frame at the top aprox. 50 mm smaller to fit a donkervoort nose-cone.
So i hope i didn't mis anything
I moved to the avon-section, bye
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