Anti roll bar

[FilW]

The anti roll bar on my car (formula Vee) is made of solid 20mm (approx) round bar. I'd like to convert it to inboard suspension and was wondering if it was possible to work out how to get about the same properties from a smaller ARB mounted inboard.
Cheers.

[breezeblock]

have a look in the race and rally car source book its got all the formula for working it out or comp car suspension

[phoenix]

Originally Posted by FilW

The anti roll bar on my car (formula Vee) is made of solid 20mm (approx) round bar. I'd like to convert it to inboard suspension and was wondering if it was possible to work out how to get about the same properties from a smaller ARB mounted inboard.
Cheers.

It's very possible but can get complicated and therefore it's easy to make a mistake.

First thing is to work out the effect of the current bar. This requires accurate measurement of a number of things. Bar diameter, bar length, lever arm length, motion ratio of the pickup point on the suspension compared with wheel movement. As a number of these values are either sqaured, cubed and even raised to the power of 4 in the equations, inaccurate measurements will lead to drastically wrong results.

Next thing is to work out how long the new bar can be made to fit in the new location, maximum length of lever arms that can be accommodated, and the motion ratio of the new inboard suspension where the bar will connect to in your design. From these things it will be possible to calculated the bar thickness required. It is quite possible that the first attempt will not work out and some part of the design will have to be changed to make things work. Unless, of course, you are copying some previous design that you know works!

If you want someone to check your figures, I volunteer! (Mad fool)

Martin

[FilW]

Thanks Breezeblock & Phoenix.
I'll get the Race & Rally book and have a read! Another other books I should read?
Pheonix when (if!) I get round to it I'll take you up on your offer to check my maths!
Cheers