havabooz

concerning espelir active GT springs

on their website they say that the rates are 6.9 up front and 9.2 in back

10mm drop all around

tein s-techs are 6.9 and 7.2

what does it mean to be 9.2 in the rear?

what are these rates in lbs/inch

ive read about spring rates and got some useful info but im still confused

havabooz

front should be 390 lbs/in and rear (from my calculations) should be a little over 500lbs/in

what does that mean concerning ride quality and stress on the stock shocks?

havabooz

stock is supposedly 314/342... so the espelir really stiffens the rates which will give less traction...but im assuming an sway bar kit will address that problem

am i correct?

ppw350Zunit

iTrader: (14)

better traction with a stiffer set-up.

Gsedan35

iTrader: (10)

That's different then what they had up before and that's way over the top for the oem shocks. I'm rather concerned because when I called mackinindustries a few months ago to ask if those springs were linear or progressive, I head the tech ask another tech who replied linear,.............they are very much PROGRESSIVE as I latter learned. Their web previously had these rates,

Espelir Z33 springs
Front:381 Rear:460 F+22% R+37%
Transfers +15% to rear

That's still up their for use with oem shocks IMO.



They also altered the G35 coupe rates, running the listed rates on the coupes softer shocks would not be a enjoyable experience, rate's have got to be wrong.

havabooz

gsedan35...you might be talking about the active super down

i am talking about the active GT....the active super down doesnt have rates listed on mackins site

the picture you psted says active super down on the box..but i think the red shocks are active GT..so its confusing

one more thing...the higher the lbs/in the more stress on the shocks?..meaning if i went from 350 lbs/in to 500lbs/in.... the shocks will be experiencing 150lbs/in more pressure than normal ..or is it not that simple?

Gsedan35

iTrader: (10)

I'm talking about the active GT rates, the rates, I posted the rates they listed as of a couple of months ago. Rates they show now don't make sense to run with oem shocks and possibly have proper shock/dampning control. Not to mention the usual worries about wearing out the oem shocks themselves. I just don't think the newly listed rates are correct, after all their techs sware the springs are linear and they were very wrong about that.

Moroccan_Mole

iTrader: (5)

the spring rating has nothing to do with putting 'stress' on the shocks.

springs control how the car's suspension handles energy and weight transfer. they hold the car up and and allow movement in the suspension. the damper (shock) controls how fast it moves up and down.

havabooz

maybe i didnt phrase it correctly but people always say that aftermarket springs will cause your oem shocks to wear down faster

i know that the springs are a seperate part from the shocks(incase you think i didnt)

if adding diff springs doesnt put more stress on the shocks then what does it do to wear them down?

Moroccan_Mole

iTrader: (5)

it's the height that causes them to wear down quicker. the oem shock/spring are matched to each other. generally aftermarket springs are shorter, this is why aftermarket springs will lower the car. now when you hit a bump or whatever, more of that energy is bieng passed onto damper. this(without getting too technical) causes the damper to 'work' more, which in turn, causes it to wear out faster.

(i hope this is right, haha ... plz somebody correct me if im wrong)

Gsedan35

iTrader: (10)

A true statement if taken in the context that most blown shocks on lowered car's can be traced to poor dampning control and too low of a drop, allowing the shocks to bottom out internally and fail. However, oem automotive shocks that are not adjustable are designed to absorb only a specific amount of input energy. The issue at hand is compounded when you consider that the structural design of the automotive shock commonly uses lower strength of materials in it's construction. Valving science is not the only reason to pay big bucks for Koni and Bilstien. Some manufactures will decline warranty claims if they learn you were running abnormally stiff springs when your shocks failed. KYB will not warranty their AGX shocks on spring rates past 450lbs.

Gsedan35

iTrader: (10)

Ok, you clarified yourself,.......all righty

THX723

iTrader: (3)

While bottoming out the shocks (from lowering) is the fastest way to break the dampers, spring rates plays a big roll in the operational life of the dampers. Exaggerated over damping and underdamping (or vice versa, i.e. over sprung and under sprung) tax the internals of the damper more than it was designed for. It has to do w. piston velocity and acceleartion. Too soft spring means piston velocity and acceleration could exceed spec during compression. Too stiff spring rates does the most damage during the rebound phase.

Hope that helps.

havabooz

now that thats cleared up..

how much of a difference in spring rates is needed between the aftermarket and oem for you to notice a positive difference

i was only considering springs with a very small drop

will the tein h-techs 360/370 not even make a difference?
what about the s-techs 390/400

any other spring drops it too much for me...so if these springs are not even worth the $$ then ill just get sways

but people swear that springs make a diff in conjunction with sways

i know you are gonna tell me to get shocks but its not cost effective right now

protocav

iTrader: (3)

the simple answer to the original question is that 1Kg/mm is roughly 56lb/in.

so if you have a 10kg spring, it is 560lb/in

Chad