Spring rates question/help

[mamamia]

Hello fellow Titan experts, I have some issues which I hope I can seek your expert opinion on.

Car : Nissan Sentra N16 2001
Suspension : Coilovers (not Titan)
Spring rates : 8kg/mm (Front) and 4kg/mm (Rear)
Tyres/rims : Stock 15" rims with GY F1-GSD3 195/55/15

I like the minimal body roll when taking corners hard, but on my way to work using highway (very bumpy highway) I find the coilovers too stiff and sometimes the car bounces too much causing me to jump!

I would like a setup such that it is still stiff overall (eg during hard cornering) but yet still comfy enough to not make me jump up and down on the highway.

Do you know if my spring rates are too stiff, especially the front? If so, what would you recommend? Noticed the Titan spring rates eg mentioned on Accoustic's very informative website for his Sunny car is quite low (<5kg/mm both front/rear)...

 

[Acoustic]

hi mamamia

my one not sunny lah :( - corolla lah :) KE70 but AE86 wanna be :)

now running 4.4 front and 3.3 rear



Always remember to balance the front and rear in such a manner to keep balance

1) car weight % front versus % rear helps to decides the ratio between front and rear.

i.e. if 8kg front versus 4 kg rear, would be for car 66% weight front 33% weight rear, no car is this bad. I think ......

2) the ratio between front spring versus rear spring - for KE70 I have listed above 1.3 is understeer, below is over and 1.3 is neutral

I don't know about Sunny, have to experiment a few times and keep record then can know.

 

[mamamia]

Hi Accoustic,
Thanks for your reply. Do you know how I can find out the overall weight distribution of my Sentra?

Eg on this website :
http://www.globalcar.com/datasheet/Nissan/2001NissanPrimera20L.htm

It doesn't say the Front/Rear weight ratios...

 

[Acoustic]

mamamia

this one I also don't know lah .... you try asking the nissan kaki :)

 

[integramania]

Hello Acoustic,

Hi there.

Just wanted to ask you what would be the best spring rates for a Perdana Sei (stock engine) on 17" rims. I got this set of HWLs and found out that its 14 front and 10 pounds on th rear. The car is really stiff. I plan to change the springs to make my ride more comfortable but yet maintain its performance.

Any idea what I should go by? was told to try something like 12 front and 5 back.

Actually not sure if this is in pounds or kg...really new to spring rates. Not sure how HWLs go by

Appreciate your help bro.

Thanks

 

[Acoustic]

Hi integramania

first of all, we still need one more parameter. either kg or lb with a displacement of either metric or imperial

i think this would help, see http://www.my-acoustic.com/Car/suspension/suspension_wisdom.htm

 

[Acoustic]

forgot to say: -

Your car original springs only between 1.x to not more than 3 kg/mm.

That's for normal cornering hence normal G-force loads.

When hard corner G-forces will be more .... but due to car mass never change
and cornering speed never double... hence the spring rate should not
increase more than double.

Hence cannot use more than 6kg any where.

 

[mamamia]

Hi Accoustic,

I got it! 66/34 F/R weight distribution for an N16....what do you think if I try to reduce the front from 8kg/mm to 6kg/mm ?

Your comments are appreciated. Thanks!

 

[Dremel]

any rough suggestion for proton satria ? i'm not sure whether mine is 6kg(F)-5kg(R) or 5kg(F)-4kg(R).. does there any label of spring rate printed on titan's spring? coz Richard seems doesn't have the record.. coz mine is 2nd hand. The only thing that he said was.. 'wah.. your spring is quite hard'

I assume mine is 6/5 or 5/4 is because i got 2 friend running on 4/3 which are sgti and putra. Theirs is abit softer than mine.. with same damping settings.