Spring Rates With Bilstein Shocks

[djr81]

I have an R32 with the SK Bilstein suspension. It is a great set up, but I reckon I have reached the point of needing a higher spring rate. (As an aside this could this be what people mean when they tell me to harden the fu(k up?).

Anyway are there any proven options out there that can marry a Bilstein shock with a higher spring rate than the Whiteline springs? Failing that what would people recommend that doesn't require pillow mounts?

[32DET]

I also have SK's setup and have the rear swaybar on medium and the front on hard...

I also feel as though i need a slightly higher spring rate as the body roll is a little too much under hard cornering...

Is that the reasoning behind why you are after higher spring rates?....Also do you have any strut braces in your car?

Cheers

Ryan

[djr81]

I also have SK's setup and have the rear swaybar on medium and the front on hard...

That is, um, unusual. Most people have the rear full hard & the front full soft - for balance.

I also feel as though i need a slightly higher spring rate as the body roll is a little too much under hard cornering...

Is that the reasoning behind why you are after higher spring rates?....Also do you have any strut braces in your car?

Yes & yes. (I am assuming you are running RE55's or similar. If not get some proper R compound tyres)

Basically in transitions the cars weight moves around a bit too much. Also you can see how much longitudinal transfer there is, ie squat under acceleration. It is a little bit the opposite under brakes.

[Sydneykid]

No problem, I have done quite a few conversions to coil overs for the Skyline guys who do a bit more circuit work and have the tyres to take advantage of the higher spring rates. Basically the conversion consists of;

2 x Front Main Springs

2 x Rear Main Springs

2 x Rear helper/tender springs

4 x Coil over conversion kits for the Bilsteins

You have 2 choices in springs, Eibach (the best) or Whiteline, pretty damn good, made in Europe, cold wound on a hydraulic coil winding machine.

The full conversion is $980 using Eibach springs and $790 using Whiteline springs, that includes delivery as usual.

The valving in the Group Buy R32GTR Bilsteins will handle up to 310 lbs/inch (5.5 kg/mm) on the front, which is around 40% more than what you currently have. The rear Bilsteins will handle up to 260 lbs/inch (4.5 kg/mm) which is around 25% more than what you currently have. The most common upgrade for the track day guys is 275/225 which works very well with the usual R type tyres (RE55, A048R, R888, D01 etc)

R33GTR Bilsteins will handle slightly more spring rate, R32/R33GTST and R34GTT slightly less.

The conversion is simple, most definitely DIY and should take less than 2 hours if you know your way around your car.

Delivery is pretty much overnight as I have most items in stock, Eibach occasionally run out of some spring rates though.

Obviously I can revalve the Group Buy Bilsteins if you are running a full slick that requires a higher spring rate.

PM me for more details.

cheers

[operationsideways]

What about just replacing the current whiteline springs with something of a stiffer spring rate?? What advantages / disadvantages does this have over swapping over to the coilover setup? I would like to get the coilover kit but after already spending a grand on the shocks/springs, it would be nice not to spend nearly that again.....

[djr81]

What about just replacing the current whiteline springs with something of a stiffer spring rate?? What advantages / disadvantages does this have over swapping over to the coilover setup? I would like to get the coilover kit but after already spending a grand on the shocks/springs, it would be nice not to spend nearly that again.....

Well that was pretty much the point - you can't get a stiffer Whiteline spring - you have to go to a coilover arrangement.

Sucks, eh?

[operationsideways]

What about other brands of springs?? Am I correct in assuming that Whiteline springs for an ECR33 will be the same as an RSR or some other brand springs and they would fit?? I have some KG/MM springs at home from when I fitted the Bilstein/Whiteline setup I would like to put in. I am in the same position as you and find the current setup far too soft on the track. And yes I do have the swaybars and good alignment etc.....

Edited July 23, 2007 by operationsideways

[djr81]

What about other brands of springs?? Am I correct in assuming that Whiteline springs for an ECR33 will be the same as an RSR or some other brand springs and they would fit?? I have some KG/MM springs at home from when I fitted the Bilstein/Whiteline setup I would like to put in. I am in the same position as you and find the current setup far too soft on the track. And yes I do have the swaybars and good alignment etc.....

Well most of the cost from SK is for the springs themselves. There isn't a huge amount of money in the rest of it.

What kg/mm are the kg/mm springs out of interest?

[operationsideways]

The springs rates were calculated by SK with my measurements and are as follows:

FRONT

Coil ID = 67/97mm

Wire OD = 12 mm

# of Coils = 9.125 turns

Spring rate = 190 lbs/inch (3.4 kg/mm) on the soft rate and 550 lbs/inch (9.7 kg/mm) on the high rate

REAR

Coil ID = 87/101 mm

Wire OD = 13 mm

# of Coils = 9.125 turns

Spring rate = 180 lbs/inch (3.2 kg/mm) on the soft rate and 400 lbs/inch (7.2 kg/mm) on the high rate

And I would not agree the springs are not most of the cost, if you went the Whiteline option @ $790 then I think you will find that the coilover kit is more then 50% of the cost... But I am still interested in fixing this issue (with limited funds) and more than likely will put these back in and see how they go but ideally I want a spring rate of around 5kg front and 4kg rear. But I just wanted to be 100% sure they will be fit so Im not wasting my time.

Edited July 23, 2007 by operationsideways

[djr81]

The springs rates were calculated by SK with my measurements and are as follows:

FRONT

Coil ID = 67/97mm

Wire OD = 12 mm

# of Coils = 9.125 turns

Spring rate = 190 lbs/inch (3.4 kg/mm) on the soft rate and 550 lbs/inch (9.7 kg/mm) on the high rate

REAR

Coil ID = 87/101 mm

Wire OD = 13 mm

# of Coils = 9.125 turns

Spring rate = 180 lbs/inch (3.2 kg/mm) on the soft rate and 400 lbs/inch (7.2 kg/mm) on the high rate

And I would not agree the springs are not most of the cost, if you went the Whiteline option @ $790 then I think you will find that the coilover kit is more then 50% of the cost... But I am still interested in fixing this issue (with limited funds) and more than likely will put these back in and see how they go but ideally I want a spring rate of around 5kg front and 4kg rear. But I just wanted to be 100% sure they will be fit so Im not wasting my time.

Um they are some pretty stiff springs. I don't think you could successfully marry them to the shocks without revalving.

I was aiming for a 5kg/mm front & 4 rear also.

Guess I was looking at the Eibach springs - which are more!

[32DET]

I will definately have to fiddle a bit more with the swaybars djr81 as that is just what i started with them at...

I will change to your specs and see how that goes.

And that kit sounds like something i might be interested in in the future Gary. But lack of funds as per usual may mean it is 6 months away yet. My car will only be driven at the track and a vary small amount on the street, e.g. maybe to the mechanics/take it round the block every now and then if it is a long time between taking it out to the track just to make sure its still alive and kicking so how would it go being driven on the street? Not too much of a worry, just a little rough?Cheers Ryan.

Also do the track guys still use strut braces on the front or rear with the stiffer spring rates you are talking about...

My car is a 32gtst.

Cheers

[Sydneykid]

Conical coil springs (which R32/33/34's have both front and rear) are expensive to manufacture, most of which is the mandrel (to wind them around) plus set up time. Hence it is only economical to make them in production runs, that's why you don't see a selection of spring rates available in the standard spring configuration. In comparison, race coils are parrallel wound and have common sizes, with 60 mm and 64 mm covering most applications. That's why there is a large range of spring rates available in race style (parrallel) coil springs.

To answer the question, yes I could have Whiteline make several different spring rates in the standard (conical) configuration, but they would have to sell for more than doing a coil over conversion. So no one would buy them.

cheers

[Sydneykid]

I will definately have to fiddle a bit more with the swaybars djr81 as that is just what i started with them at...

I will change to your specs and see how that goes.

And that kit sounds like something i might be interested in in the future Gary. But lack of funds as per usual may mean it is 6 months away yet. My car will only be driven at the track and a vary small amount on the street, e.g. maybe to the mechanics/take it round the block every now and then if it is a long time between taking it out to the track just to make sure its still alive and kicking so how would it go being driven on the street? Not too much of a worry, just a little rough?Cheers Ryan.

Also do the track guys still use strut braces on the front or rear with the stiffer spring rates you are talking about...

My car is a 32gtst.

Cheers

Last question first, the front strut brace on R32/33/34's is very worthwhile as the front upper control arms mount to the chassis at the strut towers. So a front strut brace linking the front strut towers very effectively increases the rigidity of the inner mounts of the upper control arms. Hence helping to maintain the front camber, toe and caster settings.

This is not the case at the rear since the rear upper control arms mount to the subframe, not to the chassis. So adding a rear strut brace does nothing to help maintain the rear camber and toe settings. It does add slightly to the overall chassis rigidity, so I would suggest a rear strut brace as the last upgrade on your suspension list. Whereas a front strut brace should be high on your list, if you don't already have one.

Whether or not you have a strut brace (braces) is not at all relevant to the spring rates, they are not in any way related. Springs hold the car up and absorb bumps, that's their job. Strut braces' job is to maintain the suspension geometry under load. no interdependancy there

The spring rates I use for "R" type tyres are not at all out of place in a road car, so driving to and from the event would not be a poor riding experience. For example, you could comfortably drive from Sydney to Wakefield for a track day and not need a chiropractor.

cheers

[Roy]

Does anyone have the typical corner weights you are looking for with an R32 GTSt and R32 GTR? I found the Bilstein kit to be pretty at the track, especially when combined with bigger roll bars. There was still roll but the thing was never wanting for corner speed when following the quicker cars. Only the age of mine finally got to me, over 6 years of love and abuse at the track with about 85,000 road/track kms. Even then they still drive fine and are not leaking, i think i have just found the limit of how quick i can go with what is fundamentally street suspension then on top of that is the age thing

But, i always found the big hitch was the pitch under brakes...hence why i ask about corner weighting, perhaps my rear ride height was a little too high.

[djr81]

Does anyone have the typical corner weights you are looking for with an R32 GTSt and R32 GTR? I found the Bilstein kit to be pretty at the track, especially when combined with bigger roll bars. There was still roll but the thing was never wanting for corner speed when following the quicker cars. Only the age of mine finally got to me, over 6 years of love and abuse at the track with about 85,000 road/track kms. Even then they still drive fine and are not leaking, i think i have just found the limit of how quick i can go with what is fundamentally street suspension then on top of that is the age thing

But, i always found the big hitch was the pitch under brakes...hence why i ask about corner weighting, perhaps my rear ride height was a little too high.

Roy,

I put my R on the scales at Wanneroo. With me in it & a full tank of juice the numbers were:

Front 906kg.

Rear 687 kg.

Total 1593kg.

So in perecentage terms it works out to be 57/43.

Now I weigh 100kg, a tank of petrol is about 50, so there is still a rather eye watering 1440kg of Nissan to lug around. I didn't do the corners one by one, however.

Ride height won't affect the static weight distribution, but it will affect the wheel loadings when the car pitches under brakes.

[Roy]

Ride height won't affect the static weight distribution, but it will affect the wheel loadings when the car pitches under brakes.

Yeh, was thinking it may be worth lowering the rear a tad to try and stop the pitch the car had under brakes...but never got aroudn to it

[32DET]

Thanks for that info gary!

Those percentages are interesting as well as i just assumed that a 32 GTR would have more weight bias to the front. Dunno why.

[32DET]

More than 57% that is :S

[djr81]

No problem, I have done quite a few conversions to coil overs for the Skyline guys who do a bit more circuit work and have the tyres to take advantage of the higher spring rates. Basically the conversion consists of;

2 x Front Main Springs

2 x Rear Main Springs

2 x Rear helper/tender springs

4 x Coil over conversion kits for the Bilsteins

You have 2 choices in springs, Eibach (the best) or Whiteline, pretty damn good, made in Europe, cold wound on a hydraulic coil winding machine.

The full conversion is $980 using Eibach springs and $790 using Whiteline springs, that includes delivery as usual.

cheers

Straight forward question:

Do you need the Bilsteins back to do the conversion or is it just a case of supplying parts?

[Beer Baron]

The conversion is simple, most definitely DIY and should take less than 2 hours if you know your way around your car.