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flig wishbones direction...
davimora - 12/12/17 at 01:49 PM

hi,
i have an 'uncommon' question i think.
i'm trying to make changes (CAD) in a chassis (not strictly a locost, mid-eng) for get the wheelbase i need for my replica. 220cm.
i squeezed every cm from rear side and from cockpit but still be too long.

without too much engineering and calculations (i'm not an expert at all i'm trying to change less as possible...) i found out if i flip the front wishbones from this:

BEFORE

to this (obviously moving brackets shock and steering rack):


AFTER

i can get exactly the wheelbase i want. but.. what will be the effects on handling?

i'm not going to race it, just a 'working model'.
thanks,
David

[Edited on 12/12/17 by davimora]


nick205 - 12/12/17 at 03:28 PM

Looking at your images you'll move the lower outer pivot point of the front uprights back by a large amount. I'm not a geometry expert by any means, but I don't think that's a good thing to do to the suspension geometry!


Angel Acevedo - 12/12/17 at 04:39 PM

If you move Lower balljoint any amount to the rear, you will need to move top balljoint the same amount so Caster is not Changed.
If you go "reverse" Caster, it WILL lead to a dangerous condition in which steering effort incrases with steering input.


nick205 - 12/12/17 at 05:28 PM

Assuming the front shock absorber runs between the lower wishbone and the chassis you would change the angle of it and affect the operation of it (it might not even work).


davimora - 13/12/17 at 08:52 AM

thanks to all for the feeback.
caster will not be changed as the shock absorber's angles.
i understand it's a bit risky job for save 30cm.
i will think about it (and do many CAD simulation)
have a good day!


nick205 - 13/12/17 at 09:24 AM

https://en.wikipedia.org/wiki/Caster_angle