Alfoncito wrote:Thak you Terry and Marcush for your answer I learnt a lot about reading your answer so now I trying to improve a GT car Suspension who has doble wishbone and the damper is it to 45º de between the upper and lower wishbone so I try to change this layout adding push rod suspension with rocker arm keeping the same damper so I understand the theory but how should I start to design the rocker arm I mean the lenght and ratio between the pushrod and the damper to have a lineal behaviour?that´s is what I trying to do but I don´t know how....
well mates thank you again
I hope to heard more about you
Alfoncito
Alfoncito,
Having worked with an american GT1 (Trans Am) with front rockers and recently rear rockers on a dion rear axle assembly, the reason behind the design where for the following and haven't been addressed above.
1)By moving to the rocker design the rocker ratios were allowed to be above what is availiable mounting from chassis to axle ( IE-normal config.)
2)This meant that the movement at the shock (coil overs retained) was increased as to the movement of the wheel. This meant much lower spring rates than were possible then the normal config.
3)This also meant more shock travel per movement of the wheel and more influence from the shock.
4)Whether the rocker is digressive, or progressive or one consistant motion ratio, the rocker can be designed to do all three, as a change in location of either the push rod or the shock mounting, all on the rocker and can be designed into it....which one's better, is open for debate and depends on the effect needed. Plus and minus's to each and depends on a lot of things. Having all three availiable makes the investigation possible.
5)Rocker designs allow for zero or negative droop setups, not possible in normal config.(there is a way to do this in the normal config., but I don't care to give that thought away. (Though have never found a reason to droop limit a GT car as US race tracks tend to be quite bumpy compared to European tracks)
6) Location of the ARB (anti roll bar) leverages can also be altered easily by design of mount. Even the type of roll bar could be altered. IE- going to a "T" bar design
7) Heat and heat soak will be an issue, putting the shocks that close to a V-8 engine
"Driving a car as fast as possible (in a race) is all about maintaining the highest possible acceleration level in the appropriate direction." Peter Wright,Techical Director, Team Lotus
