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tech3d
06-20-2006, 08:49 AM
Hi everyone!!
I'm designing our car bellcrank and I have some doubts about installation ratio. I know that this issue has been treated in other topics, but I hardly can guess when people are talking about motion ratios or installation ratios...

This is a question for someone who can answer in " installation ratio language"
Appart from the exact value, what is more interesting for it, to increase while bump increases or to decrease? I have read that this has to do with car's behaviour at corner entry/exit.

Is it so critical that there's not a great change from top to top?

Many thanks.

JHarshbarger
06-20-2006, 11:06 AM
In most cases you want your motion ratio to be as linear as possible, and, if anything, it should be progressive instead of regressive. Whether or not your bellcranks are in regression or progression will depend on the rest of your suspension setup. If you have modeling software at your disposal, this will help a lot because you can move parts such as your wheels and see how much your dampers are moving.

I think this is the post.
http://fsae.com/eve/forums/a/tpc/f/125607348/m/11210116...10116621#11210116621 (http://fsae.com/eve/forums/a/tpc/f/125607348/m/11210116621/r/11210116621#11210116621)

-Joel
USF SAE

KU_Racing
07-11-2006, 12:00 PM
Joel is right. In general, you should shoot for a linear motion ration with a rising rate near the end- this will give good suspension performance, and then slowly decelerate the suspension before it bottoms out or runs out of travel.