Spring Rates?

[new_to_drift]

hi i am going to be in the market for some coilovers, and ive noticed that the biggest difference between a lot of the different makes is the spring rates.And i dont really know what they are really talking about,what are the difference between different spring rates?thanks.

[new_to_drift]

oh and i drive a 89 240sx coupe if that helps.thanks.

[Oatmealman]

Not for cars,But should explain some of it,i'll get you some more

http://www.sportrider.com/tech/146_9510_tech/

[Oatmealman]

http://auto.howstuffworks.com/car-suspension.htm

[Red coupe]

zeroforum?id=44

what are you using the car for? does it see time on a race track? did you notice the bright flashing button in the upper right?

the spring rate its self is a measure of how many pounds, or kilograms it takes to compress the spring 1 inch, or millimeter (it will be metric or imperial, but is typically kg/mm)

I wouldn't chose higher then 8kg/mm front and 6kg/mm rear, and that is probably already to stiff if you are not using them on very smooth surface. for streets and mountain roads and such I would choose a bit softer or you will be loosing traction over bumps.

[BadMojo]

Suspension tuning is complicated stuff. There are entire books on the subject...books filled with stuff that makes my brain hurt.

When you see a spring rate of 8gm/mm front and 6 kg/mm rear, keep in mind that the stock springs are 2 kg/mm front and rear. This, obviously, is a huge difference. Most people seem to find 8/6 tolerable, but proper damping is important too. A cheap coilover with improper valving in the shock might feel like crap on rough surfaces while another one with the same spring rate but better damping might feel much smoother on the same surface.

Great suspension FAQ here...

zerothread?id=11638

[Red coupe]

the most amazing dampening in the world isn't gonna make 8/6 feel decent on a rough surface, the spring just doesn't give enough to absorb bumps. you can live with it, its not that bad, but its no were near what a stock car feels like...but with out proper dampening it will be even worse.

[Looneybomber]

Most people seem to find 8/6 tolerable, but proper damping is important too. A cheap coilover with improper valving in the shock might feel like crap on rough surfaces while another one with the same spring rate but better damping might feel much smoother on the same surface.

That being said, pretty much all the miata guys that have 12/9 JIC's say they ride better on the road than Konis with 7/5 ground controls. I've also heard them say they feel better than 9/6 Teins. I don't know much about 240's and their spring rates, but if the miata guys are running 7-12f/5-9r, I'm sure your heavier 240's can run those spring rates if not 1-2kg's more.

[nismofly]

different suspension design

the honda guys run upwards of 20 kg/mm all the time, same wheel rates as like a 9/7 or 10/8 on a 240

for the 240 7/5 is the most on street tires, maybe 8/6

[Looneybomber]

different suspension design

Oh good call. I'm pretty noobish sometimes when it comes to cars.

for the 240 7/5 is the most on street tires, maybe 8/6

Those are the same 2 rates I'm torn between with my miata...when I get one.

[Juujai]

yeah it depends on the shock dampening. i've sat in megan 8/6 and they feel like crap compared to tanabe dd i believe 10/8...

i'd recommend 8/6~ more or less that is what the market usually supplies us with anyway. higher spring rates typically mean better response but the higher it is the easier it is to lose control with error. low spring rates would mean lesser response but lesser margin of error. for street drivers that don't track it's fairly difficult to compare spring rates unless it gets pushed hard. because 40-50mph grocery getter turns won't have much affect.

high spring rates in the front will cause more understeer and high rates in the back will cause oversteer. typically it's heavier a tad on the front for some understeer.

[new_to_drift]

are you saying that the megan racing 8/6 feel like crap?cause those were ones i was looking at but i wont if people give negative feedback on them

[McRussellPants]

are you saying that the megan racing 8/6 feel like crap?cause those were ones i was looking at but i wont if people give negative feedback on them

You won't get any negative feedback on Megans because of who is using them. They're entry level coilovers so you'll get alot of "ZOMG THEY HANDLE SO WELL! THEY'RE 2 TIMES BETTER THAN BLOWN STOCK"... Or you'll get the Idiots that justify it by saying "Enjuku uses them" and "They're Apex-i EXVs"

Same thing for SPL, everyone swears by them because they're excellent quality but anyone whos driven on DDs or Zeals or such says their just good for what they are.

[nismofly]

Same thing for SPL, everyone swears by them because they're excellent quality but anyone whos driven on DDs or Zeals or such says their just good for what they are.

exactly, youre close to $2k before youll find stuff better than KTS, but if you have the money to spend then by all means do so

the SPL's are also appealing because of their rebuild policy and their overall good customer service

[Juujai]

yes go according to budget you can't really go wrong with megan or kts or anything better typically. just make sure it's not kei office they're gone.

99% of people with megan are satisfied for the money they paid. they work and function fine but i wouldn't put them up against anything expensive.

1100 kts vs 1700+ coilovers is pretty far of a gap. kts and megan can hold their own because of that.

[nismofly]

just make sure it's not kei office they're gone.

o_O whats this now?

[Juujai]

filed bankrupcy i believe. i inquired with driftfactory about a rebuild i wanted to do recently/shock insert replacement and they said it cant be done. also check driftfactory's site all of the kei office coilovers are taken down.

"modified"yeah i know they have no coilovers up but that's what ive been hearing around. i wonder if kazama and nams will bring out any coilovers?

the problem with buying overseas coilovers is the rebuild issue/time/price...
Modified by Juujai at 2:19 PM 2/20/2006

[nismofly]

well that sucks

actually drift factory doesnt have any coilovers listed