Rear rod axle postion

[peter parts]

Hello
My name is pierre, I am french.
In France formula vee has not had a great success, popular sport formula is " formule Renault " with national manufacturer Renault engine

I have a chassis called "formule libre" which look like formula vee


In order to modify this chassis built with vw swing axle gearbox , I seek informations for suspension tie assembly at rear of frame in the continuation of the gearbox


Having no interlocutor to question in France so I solicit you for some technical info


I understand that tie rod point of articulation is in the longitudinal alignment with side gear diff


please can you confirm it

On the other hand, I can not tell whether the point of articulation must be at the same height as the wheel shaft

i suppose that at same height there is only a variation of camber If joint is higher or lower there is slight toe variation

No toe in for rear axle but isnt it interesting to correct tranverse axis variation of the car at acceleration or braking with modification for suspension arm ball joint position

which values are correct ,

thank you very much for your informations

greeting from France
pierre

[FVRacer21]

Pierre,

I will give it a try.

if the axle tube moved up and down at a 90 degree angle to the transmission shafts, there would be no toe change.

With trailing arms (the arm "trails" the pivot point on the chassis) it is almost impossible, as the pivot point would be in the driver's compartment. So here you try to get the arm as long as possible and angle the pivot point up or down to get the preferred toe change and/or anti-dive for braking.

If you use leading arms (the arm goes forward or "leads" the pivot point) - coming from the back of the transmission going forward to the outer end of the axle tube, then you could find the correct height and distance apart so that the axle has no toe change.

For settings, the VW transaxle likes about 4 - 6 degrees negative camber total (2 - 3 degrees negative each side) depending on your tire. This setting minimizes the jacking effect. More than this and you loose hp in the axles binding at extreme angles. Suspension design varies - maybe some pictures of your car will help with suggestions.

Toe should be set about 1/16 to 1/8 total toe in (don't ask me about the degrees, but you can easily convert to mm). Check the car from static ride height 2 inches up and down and try not to have the toe go negative at any point.

Here is a good thread without pictures:

http://www.apexspeed.com/forums/show...ling-Arm/page2

Here is another:

http://formcarregistry.com/interchan...5dcde0bafb72b8

I hope this is helpful.

Chris Z