Austarion

I'll be fitting some coilovers soon and like to hear your thoughts on what weight springs would be a good starting point? Car is driven on the street and I don't want something rock hard and uncomfortable.

8K front 6K rear is a good compromise from what i hear. maybe a little softer for comfort..

I spoke to Wantsom as hey has been through a few sets with the track car. I believe for a street/track setup around 350lb in the front and 300 in the rear is a good compromise.

I've got 9k in the front and 8k in the rear of my Eterna, which is of really similar weight balance and total weight of the Starion - and I do find the front a bit hard but the rear seems spot on or close to it anyway. On the track that rate worked just fine however with the current engine's speed I don't think I was pushing the suspension to its limit.

For road driving it does seem a bit uncomfortable, especially with lower profile stiff sidewall tyres.

I'd like to know the following please:
Will the same rates work for narrow body stock struts GR2?
These are linear springs I take it
What is a K? i'm not familiar with this unit of measurement

Cheers

K = kg = kilograms

anyone got a kg to lb conversion ratio for spring rates?

redzone wrote:8K front 6K rear is a good compromise from what i hear. maybe a little softer for comfort..

S0LJAH wrote:anyone got a kg to lb conversion ratio for spring rates?

my guess its kg - mm some sort of strange metric thing prob should be measured in Newtons - being that newtons are the measurement for force in metric

however to give you the convertion 8 kg mm = ( 8 x 2.2 ) x ( 1 x 25.4 )
or 17.6 x 25.4 = 447 Lb inch

where as lb inch was the common way springs were measured to us old blokes

and 450 lb does sound a little furm I would guess that 350 - 375 would be on the money
with as said 300 rears

or (( 350/25.4 )/2.2)= 6.26 Kg - mm

www.18u wrote:I spoke to Wantsom as hey has been through a few sets with the track car. I believe for a street/track setup around 350lb in the front and 300 in the rear is a good compromise.

I will check my specs and when I have it on the road but that is very similar to mine

the group a tarmac rally car runs 330lb front, 300lb rear. but bear in mind the shell is quite a bit lighter than a widey. maybe 370/400lb font, 330lb rear??

Dave

RiceThief wrote:K = kg = kilograms

nope that would make 8k over 1760lb springs

cheaterparts wrote: however to give you the convertion 8 kg mm = ( 8 x 2.2 ) x ( 1 x 25.4 )
or 17.6 x 25.4 = 447 Lb inch

Starion_Turbo wrote:

RiceThief wrote:K = kg = kilograms

nope that would make 8k over 1760lb springs

one of us has failed at math

For what its worth - Cheater is on the money for calculations and his race set up experience would back up his comments.

My following comments need to be taken in context I am setting up for a dedicated track car running 50 series R rated tyres and some pretty aggressive front end geometry

I originally started at 250 rear and 280 front based on advice from suspension place. I found that way too soft so moved to 300 rears and 350 fronts. That was much better from a handling point of view but to remove some 'dive' under hard braking I moved to 400lb fronts which help cure the dive without compromising front end handling. The current combo is working fine on the track but would be way too stiff for street. I suggested to www18U that for a firm street ride 250-300 rear and 350 would be a good compromise given the slightly more weight of 4G54 motor up front. That combo would be a good trade off for normal street and some track work. At the end of the day you just have to experiment a little to find the right balance between handling/ride given whatever you use the car for.

cheers guys that was the conversion factor i was using just confused as some were saying arould 300lb which is way different to 8-9kgmm