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Formula BMW Suspension

Posted: 29 Jun 2006, 20:58
by f1.redbaron
Can somebody, please, explain to me, what is the point of that horizontal bar joining the two upper elements of the A-arm where they connect to the chassis (see arrow)? Thanks

Image


EDIT: Reinforcement? But what would it reinforce?

Posted: 29 Jun 2006, 21:11
by flynfrog
to help reduce a bending moment on the a arms and the mounting points

Posted: 29 Jun 2006, 21:37
by RacingManiac
anti-intrusion bar....in the event of the crash so that the a-arm don't pierce into the tub from their mounting....and jab driver in the leg...

Posted: 29 Jun 2006, 21:51
by f1.redbaron
flynfrog wrote:to help reduce a bending moment on the a arms and the mounting points
That is what I was thinking too, but then based on this picture below, you can see that the weakest point is the mounting point, and this "reinforcement" bar is just a few cm before it.

Image

RacingManiac wrote:anti-intrusion bar....in the event of the crash so that the a-arm don't pierce into the tub from their mounting....and jab driver in the leg...

That makes sense...btw, did you get a chance to see them last weekend?

Posted: 29 Jun 2006, 22:16
by zac510
Does that have a torsion bar beneath the rocker arm?

Posted: 29 Jun 2006, 22:33
by RacingManiac
No torsion bar, just monoshock...the roll is undamped....

The car that I am associated with finished 2nd in both race, I was there actually to take picture for the team....Matt Lee was the driver.

Posted: 29 Jun 2006, 23:05
by furnik28
irl and cart have them for anti intrusion. when they make the suspension arms first then drill the cross member so you can slide it on to the end of were the rose joints are then its welded in place.

Posted: 01 Jul 2006, 13:10
by i70q7m7ghw
Do those arms have a pivot where they connect to the chassis, or are they just intended to flex?

Posted: 03 Jul 2006, 11:27
by zac510
RacingManiac wrote:No torsion bar, just monoshock...the roll is undamped....
How is the roll sprung then?

Posted: 04 Jul 2006, 20:06
by MrT
The roll is sprung solely by the anti roll bar, which obviously has negligable inherant damping in itself. The Spring and damper unit only comes into action in 2 wheel bump/rebound........ horrible system really, although the aim was to seperate roll from bump, they are not truley seperated and roll stiffnesses can vary at different stages of the corner as the sping/damper unit comes in and out of effect.

Posted: 04 Jul 2006, 20:07
by luisandregg
Isn't that central element (under the monoshock front mounting point) a torsion bar? It's linked to something looking like a damper, so it would absorb roll...

Posted: 05 Jul 2006, 09:03
by MrT
No, only damper in the whole system is the main damper to control pitch. There is no torsion bar controlling roll, just the antiroll bar, which is the T shaped component mounted at the front via the two pillow blocks (an anti roll bar is in esance a torsion bar though i guess!)

Posted: 05 Jul 2006, 09:41
by furnik28
this is not what the first thread ment look at the arrow pointing to the top wishbone there is abar going west and east that tha anti intrusion bar. stop assuming this or that look at photo up and :shock: close

Posted: 05 Jul 2006, 10:56
by zac510
furnik, that question has already been answered.

luisandregg, it must be!

Posted: 01 Aug 2006, 21:21
by Powerslide
Actually, it looks as if there is no suspension for roll movement.

:cool: