Last check on my suspension.
Could some-one give his opinion?
Front:
roll-centre(stat) 45 mm above ground
bump-steer zero
My q is: is it better to gain for the not "loaded" wheel a little bit positive camber (to compensate body-roll) or result in zero or
negative camber??
By replacing the inner pivots of the upper brackets i could gain other values.
But if I place the upper lower then my static roll-centre will drop dramaticly.
So:
Could some one say how much is the movement of the wheel?
5 cm up? and 5 down?
Thnx Theo
[Edited on 8/9/06 by t.j.]
You're thinking in the right direction. Forget those cursed 'roll centres', they're not one or the other, but fictional and have
no bearing how your car behaves.
Cheers,
Syd
quote:
Originally posted by Syd Bridge
You're thinking in the right direction. Forget those cursed 'roll centres', they're not one or the other, but fictional and have no bearing how your car behaves.
Cheers,
Syd
Taking the long view the aim is to keep all 4 wheels firmly on the deck and reasonably upright at all times.
Roll centres are important but not the be all and end all -- the most important thing is that front and rear roll centres are playing in the same b
all park and sensible in relation to the cg height of the vehicle and weight distribution.
A little posative camber on the inside wheel pays dividends particularly on vehicles with soft long travel suspension but only if the roll centres
are chosen so that excessive roll stiffness from the springs and anti roll bar is not required at one end of the vehicle -- ie it dosen't
corner with only 3 wheels on the deck.
quote:
Originally posted by Syd Bridge
You're thinking in the right direction. Forget those cursed 'roll centres', they're not one or the other, but fictional and have no bearing how your car behaves.
Cheers,
Syd
The few from this forum who I have met personally, and explained this situation to, have been converted and satisfied with my explanation.
I won't put the realities on an open forum, for the same reasons that the people who enlightened me don't.
Whenever I may meet any of you, and you wish to hear my version, then I would be pleased to take the time to explain it.
Cheers,
Syd.
Yeah, right, now i know everything?????
Nobody has given an answer.
So i stick with me own design and see what happens when i drive it.
Superb or ......
Grzt Theo
quote:
I won't put the realities on an open forum, for the same reasons that the people who enlightened me don't.
TJ, what exactly are you after?
Generally you end up with some positive camber on the inside wheel when cornering. More to do with the need of a increasing (negative) camber curve
when it becomes the outside (loaded) tire than anything else. Also because you get some lift of the chassis on the inside due to body roll if your
roll centre is high (jacking effect).
I like to see 3" (7.6cm) of bump and 3" jounce for street performance or bumpy tracks. As soon as you bottom out, all your carefull
planning goes tits up and the car will try to slide off the track suddenly. If you have smooth corners you can get away with 2" or so (5cm).
Does that help?
As always my disclaimer is that my experience is with heavy cars so bear that in mind .
Syd, maybe you should explain to someone here and let them convert the masses if you are too busy to do so. I'm always up to learn new
information especially if it corrects my faulty way of thinking. You should also explain your views on anti-squat too.
Until then, there is no point gabbing about it. It's like saying you have a really hot wife but no pictures to back it up.
For once I'm more on Syd's line. Keep an eye the roll center but don't let it be your prime desigen criteria. Just look at what happen at roll, roll center for one side go down while the other side go up. You are clueless to what will happen to your RC in real life. Camber compensation, on the other hand, is something very real and use full.
quote:
Originally posted by leto
Camber compensation, on the other hand, is something very real and use full.
NOt sure there are that many more joints in the system. About 4 from memory and they are rose jointed. Cant see thats gonna cause a lot, (if any),
stiction.
Also seems to work well. A Dax with CC spanked all others, including 2 atoms, at the recent time attack at silverstone.....
quote:
Originally posted by leto
Keep an eye the roll center but don't let it be your prime desigen criteria.
The Dax system looks as if it should work fine but if so why have the combined minds of the worlds racecar designers not come up with it or copied
it.
As a point of interest the Atom is renowned for poor handling, we have a couple of customers who had them & got rid because of the handling.
Regds
Ian
Isnt it in effect just an anti roll bar?
quote:
Originally posted by iiyama
Isnt it in effect just an anti roll bar?