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What's Considered A Decent Spring Rate?

GTRPowa
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GTRPowa Rising Star

GTRPowa

Posted
Posted

My suspension is very stiff. It's fitted with Arigostas, they were on the car when I got it.

There is no markings for their spring rates, but it's the type where you simply do not want to hit any potholes period.

I've never been in another GTR to compare, even a stock one, so I don't know how stiff they are supposed to be, but my RX7 was alot softer, and still very good handling.

I assume a few people have pretty stiff suspension, it's the kind that makes panels rattle and even your keys fling around when you hit a pothole.

I see a lot of setups using 8kg front, 6kg rear. Does anyone use these? Say, the BC ones from Just Jap? - I love the Arigostas for handling, but they simply aren't suitable on a street car.

djr81 Grand Master

djr81

Posted
Posted

Too many people confuse stiff suspension with good suspension.

Stock R32 Gt-R spring rates are

front 2.4kg/mm

rear 2.7kg/mm

Pissing competitions about spring rates & how high they should be are about as useful as those centreing how much rim/tyre you can stuff under a guard.

Anyway for what it is worth I run 5kg/mm front, 4 rear. Nismo stuff is half a kg/mm higher at both ends. With the right sway bars that is enough spring for the track on R compounds. It is also a reasonable rate for the road.

If ride quality is important to you then I would avoid a rod end castor rod & get something with a decent bush in it.

MrStabby Grand Master

MrStabby

Posted
Posted

I had 10kg/8.5kg and hated it. I now have 8/6 and its much better (though they may also be related to adding some ride height), though i think a little softer would suit me best (and i like stiff suspension).

some_cs_student Veteran

some_cs_student

Posted
Posted

I'm running approx 5 / 3.2 in an R33 GTR. I find it a little hard but the dampener has plenty of adjustment that I can play with and it seems to make quite a large difference.

Ride quality is pretty good except on rough roads...which they're are plenty of in Melb :)

Car handled excellently at Sandown, Centreline was quite impressed and thought I was running semi-slicks when I was running some compliance tyres :P

rkinens Enthusiast

rkinens

Posted
Posted

R33 GTST. 10s and 8s = Crap on most roads, great on track. All depends on how much of each type of driving you do. Personally i think these are a bit stiff.....

Even race cars need some degree of compliance, although usually they have better dampers which helps.

bigmikespec Veteran

bigmikespec

Posted
Posted
Too many people confuse stiff suspension with good suspension.

Stock R32 Gt-R spring rates are

front 2.4kg/mm

rear 2.7kg/mm

Pissing competitions about spring rates & how high they should be are about as useful as those centreing how much rim/tyre you can stuff under a guard.

Anyway for what it is worth I run 5kg/mm front, 4 rear. Nismo stuff is half a kg/mm higher at both ends. With the right sway bars that is enough spring for the track on R compounds. It is also a reasonable rate for the road.

If ride quality is important to you then I would avoid a rod end castor rod & get something with a decent bush in it.

What is the reason for the higher spring rate in the rear? The Nismo S-tunes I had were like that and the Bilstein PSS9 kit that I got had similar slightly stiffer at the rear. Obviously everyone is aware of the awful weight distribution of a GTR there must eb another underlying reason.

djr81 Grand Master

djr81

Posted
Posted
What is the reason for the higher spring rate in the rear? The Nismo S-tunes I had were like that and the Bilstein PSS9 kit that I got had similar slightly stiffer at the rear. Obviously everyone is aware of the awful weight distribution of a GTR there must eb another underlying reason.

Generally a softer spring generates more grip at the end of the car it is fitted to.

On the road you don't have the same level of issues typically found on the track with things such as weight transfer etc. So you can get away such low rates.

Track cars typically need softer rear springs (relative to front) to help with traction. This is at the price of front grip & is why most track R32 Gt-r's run alot of front end neg camber, stiff rear sway bars & softer front sway bars.

bigmikespec Veteran

bigmikespec

Posted
Posted

Excellent info thanks. New springs are definitely the answer when it is time to hit the track, would 8/6 front/rear be a good starting point with a decent semi-slick? Obviously there are other factors but in general.

djr81 Grand Master

djr81

Posted
Posted
Excellent info thanks. New springs are definitely the answer when it is time to hit the track, would 8/6 front/rear be a good starting point with a decent semi-slick? Obviously there are other factors but in general.

I reckon they are too high for an R32 Gt-R.

If you have a look at the rates Nismo recommend you can't go far wrong.

For me 5/4 is good 5.5/4.5 is good too.

But as I said you need to look at three things in conjunction with this.

1 How well is the ATTESSA system working (eg do you have a controller - if you do you can arguably run a higher rear rate relative to the front.)

2. You need to address the front & rear camber angles.

3. Sway bars are needed too. Good swaybars at that.

GTRPowa Rising Star

GTRPowa

Posted
  • Author
Posted (edited)

Interesting. Yeah mine has the adjustable dampers but it just goes from stiff, to stupid stiff.

When you jack the car up the wheels lift off the ground about half an inch after the car, when you pull into deep driveway drains at an angle the car will teeter on the 2 corner wheels, sometimes I have to roll back and get a run up (especially noticable in 2WD when I had my shafts out).

I don't think it's an issue of being a girl, it's that stiff it's putting stress on the car. I can only assume they are 9+kg. I simply want to replace the whole set.

Where can I obtain coilovers with ~4-5kg rates? I only find 6-8's, and higher.

Edited by GTRPowa
djr81 Grand Master

djr81

Posted
Posted
Interesting. Yeah mine has the adjustable dampers but it just goes from stiff, to stupid stiff.

When you jack the car up the wheels lift off the ground about half an inch after the car, when you pull into deep driveway drains at an angle the car will teeter on the 2 corner wheels, sometimes I have to roll back and get a run up (especially noticable in 2WD when I had my shafts out).

I don't think it's an issue of being a girl, it's that stiff it's putting stress on the car. I can only assume they are 9+kg. I simply want to replace the whole set.

Where can I obtain coilovers with ~4-5kg rates? I only find 6-8's, and higher.

Is it a 32 or a 33? Your thingo says a 32 but the post a couple previous says 33.

Again look to the Nismo rates for the thing. You will see the rates on a 33 are harder.

GTRPowa Rising Star

GTRPowa

Posted
  • Author
Posted
Is it a 32 or a 33? Your thingo says a 32 but the post a couple previous says 33.

Again look to the Nismo rates for the thing. You will see the rates on a 33 are harder.

It's a 32, I didn't notice I indicated anywhere I had a 33, but nah only a 32. It just does my back in.

bigmikespec Veteran

bigmikespec

Posted
Posted
Is it a 32 or a 33? Your thingo says a 32 but the post a couple previous says 33.

Again look to the Nismo rates for the thing. You will see the rates on a 33 are harder.

Apologies, I hijacked the thread a bit... I have a 33.

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