EK9 spring rates

[dave_yd]

hi,

im building my ek9 for track and a bit of road, im looking to get the KW version 2 coilovers from a guy on HT

what springrates do you reccomend, the guy im possibly buying them off used 800lb front and 1200 rear i presume this is a bit extreme for my purpose? he had them on a race car.

My setup will be as follows:
approx 400 bhp on track
all new hardrace bushes
fully adjustable camber and toe
fully braced
possibly a cage

thanks
Dave

 

[blinx9900]

250lb linear front, 250lb progressive rear

note: 250lb/in = 4.75kg/mm

edit: nevermind, i though you were asking about factory spring rates

now to answer your question, the spring rates on those KW are not that high for a true track car, i just don't personally like the rear sprung so much stiffer than the front. i also wonder if the shocks on those coilovers are valved for that stiff of a spring on the rear.

 

[dave_yd]

just to clarify, when i say track i mean circuit race car not drag car.

 

[blinx9900]

Don't worry i know but good to clarify, it would be funny if you went out and bought something based on what we all said and it was for a different form of racing

 

[dave_yd]

lol, would be a nightmare,

whats the purpose for really stiff springs on the back, i always thought the fronts were stiffer unless drag racing?

 

[johnny-ek9]

My HKS Hipermaxx 2's are 10 front and 8 rear, i wouldnt say they would be far off for the track!

 

[jugbugz]

I agree with blinx, I dont like the rears too stiff. EK9s oversteer a bit.

 

[blinx9900]

lol, would be a nightmare,

whats the purpose for really stiff springs on the back, i always thought the fronts were stiffer unless drag racing?

to get the back end to slide out more to counter the FWD vehicles natural tendency to understeer...

 

[DedeSIR]

I can confirm on that...

When I bought my coilovers, I initialy install the 12 kg spring up front
and 8kg rear. Understeer and understeer. I've switch the 12kg at the
back and it became pretty much neutral. A lot more fun to drive....
on the track. In the street the 12kg at the back is on the rought side .

 

[saxophonias]

250lb linear front, 250lb progressive rear

note: 250lb/in = 4.75kg/mm

edit: nevermind, i though you were asking about factory spring rates

now to answer your question, the spring rates on those KW are not that high for a true track car, i just don't personally like the rear sprung so much stiffer than the front. i also wonder if the shocks on those coilovers are valved for that stiff of a spring on the rear.

I didn't have that in mind..So how come the aftermarket be so stiffer in terms of spring rates... Any ideas?

 

[blinx9900]

I didn't have that in mind..So how come the aftermarket be so stiffer in terms of spring rates... Any ideas?

Because factory cars ride a lot higher off the ground so they have more suspension travel, the lower a car is the stiffer the spring must be to keep it from hitting the ground, it also affects the handling as a car with stiffer springs has less body roll, but stiffer springs are also uncomfortable for most so OEM springs are usually very soft... you should see how soft the NON-type R springs are, i think something like 90lbs in the rear!!

 

[saxophonias]

i see! Imagine the springs of ek2/3 or egs.. I remember my ej9 as stock (dx oem set up) was too soft and understeerish. Non typeR owners use to say that double wishbone suspension is gone wasted with the sluggish oem set ups.. Unfortunately in Greece we never had the chance to have an ek9 and see how it feels in corners. Only what we can see from jdm BM videos..