Fortune Auto 500 coilover unboxing
Oct 10, 2012, 01:55 PM
#17
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It depends on how you are using the car, nothing suspension is black and white.
Standard street set-ups use higher rates in the front cuz that's where all the weight is (engine/tranny etc), and they are not intended to be driven hard. But for the track you want them to be at least the same (like 9/9 or 10/10). For my suspension/rear diff it's better to have the rear's slightly stiffer than the front. Conversely, for the X you want the front and rears to be the same (great chassis balance, and an electronic rear diff).
I've been using 8/7, and the fronts need just a bit more stiffness for my liking (so I went to 9). By bumping the rear's up a bit more, it helps the mechanical diff to rotate easier (electronic diffs don't care) as well as high speed stability (nothing scarier than the back end starting to bounce at 120mph in T8 of Big Willow). I "was" going to do 9/11, but I chickened out (still my DD).
Unless you get really high rates (like 14+) helper springs are pointless.
Roller bearing are to help keep the ruckus to a minimum.
As for Swift's....well their reputation preceed's them (and they made a DRAMATIC improvement in my BR's when I upgraded after the fact).
Last but not least, yes I got rear extenders (I'm going to have RRE do the install and cut through the two pieces of metal that encapsulates the rear strut tops)
Last edited by sstevojr; Oct 10, 2012 at 02:05 PM.
Oct 10, 2012, 02:43 PM
#18
Cuz 10 is too hard and 8 is too soft
It depends on how you are using the car, nothing suspension is black and white.
Standard street set-ups use higher rates in the front cuz that's where all the weight is (engine/tranny etc), and they are not intended to be driven hard. But for the track you want them to be at least the same (like 9/9 or 10/10). For my suspension/rear diff it's better to have the rear's slightly stiffer than the front. Conversely, for the X you want the front and rears to be the same (great chassis balance, and an electronic rear diff).
I've been using 8/7, and the fronts need just a bit more stiffness for my liking (so I went to 9). By bumping the rear's up a bit more, it helps the mechanical diff to rotate easier (electronic diffs don't care) as well as high speed stability (nothing scarier than the back end starting to bounce at 120mph in T8 of Big Willow). I "was" going to do 9/11, but I chickened out (still my DD).
Unless you get really high rates (like 14+) helper springs are pointless.
Roller bearing are to help keep the ruckus to a minimum.
As for Swift's....well their reputation preceed's them (and they made a DRAMATIC improvement in my BR's when I upgraded after the fact).
Last but not least, yes I got rear extenders (I'm going to have RRE do the install and cut through the two pieces of metal that encapsulates the rear strut tops)
It depends on how you are using the car, nothing suspension is black and white.
Standard street set-ups use higher rates in the front cuz that's where all the weight is (engine/tranny etc), and they are not intended to be driven hard. But for the track you want them to be at least the same (like 9/9 or 10/10). For my suspension/rear diff it's better to have the rear's slightly stiffer than the front. Conversely, for the X you want the front and rears to be the same (great chassis balance, and an electronic rear diff).
I've been using 8/7, and the fronts need just a bit more stiffness for my liking (so I went to 9). By bumping the rear's up a bit more, it helps the mechanical diff to rotate easier (electronic diffs don't care) as well as high speed stability (nothing scarier than the back end starting to bounce at 120mph in T8 of Big Willow). I "was" going to do 9/11, but I chickened out (still my DD).
Unless you get really high rates (like 14+) helper springs are pointless.
Roller bearing are to help keep the ruckus to a minimum.
As for Swift's....well their reputation preceed's them (and they made a DRAMATIC improvement in my BR's when I upgraded after the fact).
Last but not least, yes I got rear extenders (I'm going to have RRE do the install and cut through the two pieces of metal that encapsulates the rear strut tops)
Oct 10, 2012, 03:13 PM
#19
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I would "think" that you want a really stiff rear end for max rotation. AutoX is all sharp turns, a few small straights, yes? 9/9 is as good starting point, worst case scenario you buy a new pair of springs for the rear (about $150 for a pair of Swift's).
Oct 11, 2012, 08:15 AM
#23
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you pick higher or equal rear spring rate because of the motion ratio. obviously they aren't the exact same as the Evo, but there's not much info to go on as far as RA's
http://www.evoxforums.com/forums/showthread.php?t=66230
and remember that there's not too much reason to go above 10k on street tires - they don't have the grip to support the spring rates
picking stiffer front rates "because we're nose heavy" is very one-dimensional thinking
http://www.evoxforums.com/forums/showthread.php?t=66230
and remember that there's not too much reason to go above 10k on street tires - they don't have the grip to support the spring rates
picking stiffer front rates "because we're nose heavy" is very one-dimensional thinking
Oct 11, 2012, 09:53 AM
#24
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and remember that there's not too much reason to go above 10k on street tires - they don't have the grip to support the spring rates
picking stiffer front rates "because we're nose heavy" is very one-dimensional thinking
picking stiffer front rates "because we're nose heavy" is very one-dimensional thinking
Oct 11, 2012, 09:59 AM
#25
I read that post, Andrew wrote
"For the front EVO with the strut based suspension, it's close to 1 (almost). For the rear, it's somewhere between .6 to .9".
So, if its off why should the spring rates be the same? Is it because the weight of the engine that compensates for the difference therefor the rates when getting springs should be identical? If they should be identical why are the rates different with stock suspension?
Im confused, at the start of the post you say to get equal F/R, but near the end guys are saying to get a stiffer rear. argh.
"For the front EVO with the strut based suspension, it's close to 1 (almost). For the rear, it's somewhere between .6 to .9".
So, if its off why should the spring rates be the same? Is it because the weight of the engine that compensates for the difference therefor the rates when getting springs should be identical? If they should be identical why are the rates different with stock suspension?
Im confused, at the start of the post you say to get equal F/R, but near the end guys are saying to get a stiffer rear. argh.
Last edited by crak; Oct 11, 2012 at 10:05 AM.
Oct 11, 2012, 10:05 AM
#26
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His comment was specifically for the VIII/IX, which is a FWD-based chassis. Those cars want a higher rate in the rear.
Same principle for the X, but a better balaced chassis, means the rears can be equal to the fronts.
The front supports the mass of the car, the rear supports less mass but also a less effective fulcrum point.
Mathematically speaking:
A ration of 1 eans 600=600
A ratio of .8 means 600=480
Notice how both use the same "spring rate" to support different mass??
SO, now we apply it our equally awesome chassis, with multi-link in front and rear. We should also have rates that are nearly the same.
Specifically FA defaults to a 8/7 configuration for the street ( seems like SOME manufactures actually check these things ahead of time, none of that 6/4 nonsense).
I choose to go 9/10 for a bit better rear end rotation, as our diff doesn't have the electronic clutch plates to push around grip (it also doesn't break from a violent sneezing, lol), so it needs a bit more to keep the rear end down on rotation(I'm also *** heavy by ~100 lbs).
Same principle for the X, but a better balaced chassis, means the rears can be equal to the fronts.
The front supports the mass of the car, the rear supports less mass but also a less effective fulcrum point.
Mathematically speaking:
A ration of 1 eans 600=600
A ratio of .8 means 600=480
Notice how both use the same "spring rate" to support different mass??
SO, now we apply it our equally awesome chassis, with multi-link in front and rear. We should also have rates that are nearly the same.
Specifically FA defaults to a 8/7 configuration for the street ( seems like SOME manufactures actually check these things ahead of time, none of that 6/4 nonsense).
I choose to go 9/10 for a bit better rear end rotation, as our diff doesn't have the electronic clutch plates to push around grip (it also doesn't break from a violent sneezing, lol), so it needs a bit more to keep the rear end down on rotation(I'm also *** heavy by ~100 lbs).
Last edited by sstevojr; Oct 11, 2012 at 10:10 AM.
Oct 11, 2012, 11:48 AM
#27
Yeah, thats not a bad idea, I noticed when i do autox I have a **** ton of understeer. So, I might want to get a stiffer rear 9/10, to swing my *** end out more. I see where this is going now.
Right on. Thanks for clarifying that to me! (Who knows maybe at the time, my tire pressure sucked and thats' why I had understeer) Then again I had stock tires and suspension. Ever race the ralliart and notice the understeer?
On my autocross forum they referred me to this link:
http://farnorthracing.com/autocross_secrets18.html
think its of any use? or 50 good stuff/ 50 outdated and bogus?
Right on. Thanks for clarifying that to me! (Who knows maybe at the time, my tire pressure sucked and thats' why I had understeer) Then again I had stock tires and suspension. Ever race the ralliart and notice the understeer?
On my autocross forum they referred me to this link:
http://farnorthracing.com/autocross_secrets18.html
think its of any use? or 50 good stuff/ 50 outdated and bogus?
Last edited by crak; Oct 11, 2012 at 12:07 PM.
