R32 Gtr Spring Rates Help

[ujin]

Hey guys,

i just purchased a set of tein super racing coilovers and realised that they did not come with springs! well. i am stuck for choice as tein has a huge variety of spring rates to choose from to match the shocks. the recommended settings for the shocks are 12kg front and 12kg rear. however this setting is optional and i was wondering if i sould be using harder spring rates at the front coz of the big six? i would be matching them up with 265 or 275 simi-slicks for track use so i think i shld be fine with 14 kg max?

thanks for your help guys!

[T-Rex]

From what i have read, for a street/track car spring rates closer to 5kg front and 4kg rear is more like it. The stiff rates can cause brakes locking up when braking over bumps, and can cause the car to "skip" over the bumps and not actually get traction. If its mainly a track car you could probably got stiffer than 5/4 but I'm not a pro on that.

My R32 street car has the crappy D2 coilovers with about 12kg/12kg rates and they are horrible on bumps!

[bnr#@]

Tein shocks will only take around a plus minus 2kg spring rate from what they were originally intended to run due to their valving so you cant go to soft a spring on them.

I would suggest you run what they were designed to run as it is a fairly high end shock and that combo was developed especially for the car you have.

I would no worry about running a heavier front spring then rear, the 12kg is already heavy enough to support the heavy front end.

As an example the nismo R tune coil overs used 9kg front and 9.8kg rear springs

[Sydneykid]

Keeping in mind that the movement and leverage ratios are the same front and rear, for a car with 65/35 front rear weight distribution does it really make sense to have 50/50 spring rates? Think about what that means. Simplistically, for the same sized bump the front spring is going to compress ~50% more than the rear spring, how do you think that is going to affect the ride and handling?

Cheers

Gary

[nisskid]

for a car with 65/35 front rear weight distribution

holy shit, didnt think it was that bad, wow.

[Duncan]

well my gtr came out at 60/40 but its still appalling http://www.skylinesaustralia.com/forums/R3...l=corner+weight

12kg springs are terrifying. sounds like its off a supercar or something.

[ujin]

thanks for your help guys! makes sense to have higher rates at the front i suppose. prob 12 front and 10 rear? or 11 rear?

[Sydneykid]

well my gtr came out at 60/40 but its still appalling

Add the usual road car aircon and ABS and it's closer to 65/35.

12kg springs are terrifying. sounds like its off a supercar or something.

Nope, don't use that sort of effective spring rate in a V8Supercar, not even on a relatively smooth, high g force circuit like Philip Island.

Cheers

Gary

[MrStabby]

FWIW i had 10 front 8.5 rear and they sucked. Driving instructor told me the rear in particular was too stiff. (full weight street GTR, Falken RT-615 tyres). With fat semi slicks and a super smooth track you might just get away with 10 front 8 rear, but if I were you i'd ask what rates they use in the motorsport forum.

I now have 8.2 front and 6.4 rear and they work FAR better on the track and street - still very firm tho. These came off a lightened, full slicked, 400+kw car and were his oran park setup.

[djr81]

Try half the 12 & 10kg/mm rates listed, ie 6 & 5 kg/mm. Which sounds like it is well outside the window for the shocks.