Using car springs.

[Edward M. Kasprzak]

Cant you give me general damping and spring values for a 280kg car

Yes, I can. But the idea is for you to learn, not for me to show you that I have already learned.

You have other resources. Google is your friend. In the past some teams have posted their design reports on their team websites, or have quoted suspension values on a "specifications" page. Some digging will give you rough values. Some papers on FSAE vehicles also have suspension values. And some of those can be found via links or references buried in these fsae.com forums.

You have that "I need a number now and don't want to think about it or learn anything" sound, which concerns me. At least you're persistent in asking questions. Above are a few more ways for you to find the information you're seeking. Let's refocus your persistence into a good internet search session. You can get there from here.

And note: Information isn't knowledge. The latter will take time and effort to develop. You have a very short term goal, but our educational goals are on a much longer timescale. Someone may throw you the value you seek, and that's up to them, but engineering is about knowledge and understanding. Unless you have a context for the values you find you will have nothing more than ballpark numbers.

Edit: Matt, you beat me to it! At least we said a lot of the same things.

[Claude Rouelle]

To I Don't know what I am doing (don't worry me neither) from Edinburgh,

This could help you too

http://www.optimumg.com/technical/technical-papers/

[Tim.Wright]

That book is £66 and will take weeks to arrive, quite a lot if I am still at such basic levels. Cant you give me general damping and spring values for a 280kg car so I don't waste time looking at direct suspension only to find I will have to have the springs custom made or something...

For fuck sake, do some engineering... Why take part in FSAE if you are just going to buy everything off the shelf based on calculations that you expect everyone else to do for you???

BTW, what you are referring to as "wasting your time" is known in the industry as a "concept evaluation" and is the decision which underlines your whole development direction.

And you want to palm this off on someone else. Nice...

[I_dont_know_what_im_doing]

I'm back on Monday and I'll try to figure out spring rates and damping forces then.

I can do the free body diagram without a book, but need more information for springs. I'll work out exact values next week but I just needed general values for talking to the suspension guy on the phone and so I know my numbers are with in a resonable amount and not magnitudes low or high.

[Claude Rouelle]

"Cant you give me general damping and spring values for a 280kg car so I don't waste time looking at direct suspension only to find I will have to have the springs custom made or something..."

No, no, no.... And NO!

For a moment I thought that was another Indian question but as I see simplistic and entitled questions can come from everywhere. If anybody would be giving you silver spooned solutions, it would defeat the very purpose of FS/FSAE which is for you to better search, apply and execute engineering methods.

You_better_know_what_you_are_doing

PS 280 kg car with or without driver? Even with driver and even with a 4 cylinders that is already pretty heavy...

[dynatune]

For novices like you ... have a look at the demo version of Dynatune for Excel. With elementary data you can get a lot done ....

Cheers,
dynatune, www.dynatune-xl.com