Ive been looking around at all my suspension options and notice that nearly every spring company makes springs, for FWD cars, extremely harder in the front than in the back. Ok, so there is added weight in the front to deal with, understand that. buy dont we all know that to reduce understeer the back suspension needs to be nearly as hard as the front......i thought that was grade school shit.

[Edited on January 10, 2006 at 1:22 AM. Reason : wasnt paying attention... like it matters]

1/10/2006 12:58:46 AM

youre an idiot.

1/10/2006 1:00:04 AM

enlighten me oh holy one

1/10/2006 1:01:52 AM

^^

1/10/2006 1:04:43 AM

^^^

1/10/2006 1:05:57 AM

fwd

body roll + camber = compromised contact patch + traction loss @ drive wheels and YOU NEED THAT TO CUT THE APEX IN THE TWISTIES MAN

[Edited on January 10, 2006 at 1:09 AM. Reason : {/gay ass autox'n college kid}]

1/10/2006 1:09:08 AM

...... i guess you dont know what im getting at here. for example one spec i saw was 4kgf/mm rate in front and like 2.2kgf/mm in the back. Now tell me 4 in the front and 3-3.5 in the back wouldnt handle better. why make the front hard and leave the back soft?

[Edited on January 10, 2006 at 1:23 AM. Reason : asd]

1/10/2006 1:20:16 AM

Ok just looked at some true race spec springs used for N1 13kg in the rear and 12kg in the front. explain

1/10/2006 1:35:36 AM

go play gran turismo or something

1/10/2006 1:59:41 AM

if you know suspension more than them, get coilovers, pick your spring rates, set your damping and stfu

1/10/2006 2:51:13 AM

so what he's trying to say is that he knows more about a line of work that he has absolutely no experience in than the people that have done it as a career and make all these cars that people drive work right and that they missed a huge point somewhere in developing suspension for cars and that is why it never works for most cars out there....right? x3

1/10/2006 10:38:41 AM

Quote :

"body roll + camber = compromised contact patch + traction loss @ drive wheels and YOU NEED THAT TO CUT THE APEX IN THE TWISTIES MAN"

could you explain a little further? what kind of car and situation are you referring to? straightforward questoin here

1/10/2006 10:44:23 AM

Quote :

"fwd"

1/10/2006 10:51:36 AM

get something RWD and be done with it

FWD is gay

1/10/2006 11:14:51 AM

most of you nigger wouldnt know the difference between the two.

1/10/2006 11:58:16 AM

Yo Duke!

Does that mean I'm gay?

1/10/2006 12:06:10 PM

Duke won't be able to answer that. He is a big believer in the "don't ask, don't tell policy."

1/10/2006 12:44:19 PM

You guys are retarded. If there is a good reason for springs being made like that, then what the hell is it? You act like you know everything in the world, yet i havent seen one good answer presented. If you are so goddamned smart take some time and explain

1/10/2006 1:26:41 PM

Quote :

"so there is added weight in the front to deal with"

1/10/2006 1:51:38 PM

A spring with a lower spring rate can be "harder" than a spring with a higher spring rate if has less weight on it.

1/10/2006 2:23:27 PM

Quote :

"youre an idiot."

Actually I like this answer better.

1/10/2006 2:24:43 PM

^^^
^^

and

^

1/10/2006 2:56:51 PM

^^^there's your answer, right there, although with questionable verbage from an engineering perspective (higher frequency under oscillation...not "harder". )

say a car has stock spring rates of 1000 lbs/inch front, and 500 lbs/inch rear. If you outfit it with aftermarket springs with rates 1500 lbs/inch front and 1000 lbs/inch rear, you've of course made it stiffer all around, as well as configured it more towards oversteer (or more likely, less understeer).

it's a relative thing. it's not like "stiffer springs in front=understeer, same all around=neutral, stiffer springs in back=oversteer".

for that matter, suspension is kind of black magic, anyway. there are a metric shit ton of interrelated variables that go into it, but the above is the simple answer.

[Edited on January 10, 2006 at 3:02 PM. Reason : FEAR THE MECHANICAL ENGINEERS]

1/10/2006 3:00:39 PM

Uh oh....time to jump in to the melee here...

Duke's right on.

Don't forget, too, that required spring rates also have a lot to do with the actual suspension geometry and the spring's relative position in relation to a control arm's geometry and the resulting moments about the control arm's axis of rotation.

If the moment arm created at the tire's contact patch is significantly greater than that on which the spring acts, then significantly greater rates are required to maintain equilibrium. For dynamic equilibrium and adquate control, even greater rates may be needed.

I'm sure a good deal of research is done on many spring combos, but often the recommended combos are only a starting point, as applications differ greatly, and even setups differ greatly per application. Duke says that this is a black art, and it is in a lot of respects. Not EVERYTHING can be solved IN A TIMELY OR AFFORDABLE MANNER purely by the use of applied mathematics; trial and error is STILL the predominant means of reaching an acceptable goal in most fields of engineering.

I'd be willing to bet that somewhere in every spring company's literature they include notes that your results may differ based on your application.

All this said, it's true that stiffer rates in the back will induce more oversteer (or help to eliminate excessive understeer)...to an extent. Same goes for stiffer springs up front reducing oversteer. But a LOT more variables exist here, and these are only a starting point.

You present an overly simplistic argument that in reality has many more facets than you've brought to the table. We can sit down and discuss this at length if you'd like.

1/10/2006 3:23:40 PM

Quote :

"You guys are retarded. If there is a good reason for springs being made like that, then what the hell is it? You act like you know everything in the world, yet i havent seen one good answer presented. If you are so goddamned smart take some time and explain"

I don't recall people in here acting like they know anything except your ignorance. I simply pointed out that people that do that shit for a living most likely know what they are doing since most cars seem to work properly the way they should. I believe that before they just shit parts onto an assembly line and hope the car comes out alright that they research analyze and test many different methods on all parts of the car and that everything works the way it does and is the way it is for a reason that has been thought out. If your "elementary" idea is so fucking good then why don't you call up GM or Honda or some other big name company and see what their engineers have to say to you. They should bow down and suck you off from the way you talk, hell they'd atleast give you a job redesigning every car made in the decades past with this problem. If its such a novel idea then you shouldn't have told anyone and made money off of it yourself redesigning suspension and making a super nice car. My question for you is why have you not done that yet? I bet you don't have an answer for that do you? I'll answer it for you, its because you are a fucking idiot. I have a feeling if you presented this to any company you'll get owned even more than you already have. I don't know the exact reasons of why or how they are how they are now but I know that people are paid to do the work and that make shit go together and work right do know. They know more than you.

[Edited on January 10, 2006 at 4:59 PM. Reason : ]

1/10/2006 4:55:20 PM

Quote :

"Quote : "body roll + camber = compromised contact patch + traction loss @ drive wheels and YOU NEED THAT TO CUT THE APEX IN THE TWISTIES MAN" could you explain a little further? what kind of car and situation are you referring to? straightforward questoin here"

you seriously want me to explain a joke?

1/10/2006 9:02:35 PM

it also has to do with sprung vs. unsprung mass, wheel rates, roll rates, etc.

for a comprehensive discussion, see if the library has this book:

Race Car Vehicle Dynamics
http://www.sae.org/servlets/productDetail?PROD_TYP=BOOK&PROD_CD=R-146

1/10/2006 9:15:15 PM

what the fuck sway to the music batman the goblin wont sing your terrible harmonicals dragoning slaying ghooplernickle.



down with the king widget hound!

1/11/2006 1:20:46 AM

Quote :

"Don't forget, too, that required spring rates also have a lot to do with the actual suspension geometry and the spring's relative position in relation to a control arm's geometry and the resulting moments about the control arm's axis of rotation. If the moment arm created at the tire's contact patch is significantly greater than that on which the spring acts, then significantly greater rates are required to maintain equilibrium."

oh yeah, i didn't even think about that. durrrrrr.

i was gonna say that you picked an exceptionally complicated way of trying to communicate something very simple, but a simpler way isn't really coming to mind right now. I might actually think about it later and try to explain it in small words.

1/11/2006 1:26:02 AM