How Do I Tell What My Spring Rates Are?

[some_cs_student]

My Ohlins just happen to be on the garage floor

Front

13.8mm wire

7.5 Coils

92.5mm od

Rear

13.2mm wire

9.25 Coils

92.5mm od

In my opinion , they are hard ...

From memory SydneyKid is using an industry standard on the material used, it will vary a little though but this is only a free estimation service.

Are you also running the Ohlins (yellow coloured springs) on an R33 GTR?

On my ohlins I had a bit of trouble working out whether it was 12mm or 13mm wire....

Rear Front

Coil ID = 88/79 mm Coil ID = 90/88 mm

Wire OD = 12 mm Wire OD = 13 mm

# of Coils = 9.125 turns # of Coils = 7.2 turns

I was measure coil ID (across the top) and found it was different each way, I'm not 100% sure if these measurements are accurate as I did them just before I put them back on the car.

My estimated spring rates were 3.33kg/mm rear and 4.66kg/mm front, but they seem pretty damn solid on the road.

Just curious so we can compare our rates.

Regards,

Gareth

[Sydneykid]

Wouldnt the spring hardness and material effect the rate ?

How can you tell rates without knowing that ?

Or does it assume everything is a "standard"

Ignore that bit you have already answered it several times .....

Hey "I was elected to lead , not to read"

My Ohlins just happen to be on the garage floor

Front

13.8mm wire

7.5 Coils

92.5mm od

13 kg/mm (735 lbs/inch)

Rear

13.2mm wire

9.25 Coils

92.5mm od

8.5 kg/mm (480 lbs/inch)

In my opinion , they are hard ... I agree, simply rediculous

Cheers

Gary

[Sydneykid]

From memory SydneyKid is using an industry standard on the material used, it will vary a little though but this is only a free estimation service.

Are you also running the Ohlins (yellow coloured springs) on an R33 GTR?

On my ohlins I had a bit of trouble working out whether it was 12mm or 13mm wire....

Rear Front

Coil ID = 88/79 mm Coil ID = 90/88 mm

Wire OD = 12 mm Wire OD = 13 mm

# of Coils = 9.125 turns # of Coils = 7.2 turns

I was measure coil ID (across the top) and found it was different each way, I'm not 100% sure if these measurements are accurate as I did them just before I put them back on the car.

My estimated spring rates were 3.33kg/mm rear and 4.66kg/mm front, but they seem pretty damn solid on the road.

Just curious so we can compare our rates.

Regards,

Gareth

Rear = 3.2 kg/mm

Front = 5.0 kg/mm

Cheers

Gary

[some_cs_student]

Rear = 3.2 kg/mm

Front = 5.0 kg/mm

Cheers

Gary

Thanks SydneyKid, I thought they were hard. I either measured them wrong or I'm too fussy

[KURAUN]

Front

Coil OD = 85mm

Wire OD = 11.5 mm

# of Coils = 7.125 turns

Back

Coil OD = 85mm

Wire OD = 11.5 mm

# of Coils = 9.125 turns

they are buddyclub coilovers

[Sydneykid]

Front

Coil OD = 85mm

Wire OD = 11.5 mm

# of Coils = 7.125 turns

8.5 KG/MM (470 LBS/INCH)

Back

Coil OD = 85mm

Wire OD = 11.5 mm

# of Coils = 9.125 turns

6 KG/MM (340 LBS/INCH)

they are buddyclub coilovers

Typical Buddy Club spec

Cheers

Gary

[KURAUN]

Typical Buddy Club spec

Cheers

Gary

ahk kool

thanks Gary

[beersandwich]

Coil OD = 80mm

Wire OD = 10.5 mm

# of Coils = 5 turns

their coil over springs, so do i count the last part of the spring where it tapers off (to make it flat)?

[Sydneykid]

Coil OD = 80mm

Wire OD = 10.5 mm

# of Coils = 5 turns

their coil over springs, so do i count the last part of the spring where it tapers off (to make it flat)?

Yes

Cheers

Gary

[beersandwich]

then try this

Coil OD = 80mm

Wire OD = 10.5 mm

# of Coils = 7 turns

[Sydneykid]

then try this

Coil OD = 80mm

Wire OD = 10.5 mm

# of Coils = 7 turns

375 lbs/inch (6.7 kg/mm)

Cheers

Gary

[Russman]

I've got some Cusco coil-overs. Very stiff.

FRONT

Coil OD = 90mm top and bottom

Wire OD = 13 mm

# of Coils = 9 turns

Spring rate =

BACK

Coil OD = 89mm top and bottom

Wire OD = 12 mm

# of Coils = 7.5 turns

Spring rate =

Thanks.

[Sydneykid]

I've got some Cusco coil-overs. Very stiff.

FRONT

Coil OD = 90mm top and bottom

Wire OD = 13 mm

# of Coils = 9 turns

Spring rate = 485 lbs/inch (8.7 kg/mm)

BACK

Coil OD = 89mm top and bottom

Wire OD = 12 mm

# of Coils = 7.5 turns

Spring rate = 465 lbs/inch (8.3 kg/mm)

Thanks.

Cheers

Gary

[Levi_]

Here's a quick Spring Rate Calculator I put together in Flash, I'll do a nicer JavaScript version if people are interested.

http://skylines.wtf0.com/springrate/

[Sydneykid]

Here's a quick Spring Rate Calculator I put together in Flash, I'll do a nicer JavaScript version if people are interested.

http://skylines.wtf0.com/springrate/

Good job, save me some time. It works OK for race style springs ie; ground flat both ends, but overrates normal Skyline configuration by around 15%

Cheers

Gary

[260tech]

Good job, save me some time. It works OK for race style springs ie; ground flat both ends, but overrates normal Skyline configuration by around 15%

Cheers

Gary

Hi Gary, out of interest what spring-rates are the Eibach jobs you supplied me earlier this year for my Stagea & have you come up with an install guide as yet. I have installed front setup on my car (short jobs), ended up setting at forth groove up from bottom of Bilstein, lower thread exposed aroung 66mm to give 370mm ride height but am still to get to suspension shop to do rear camber bushes & rear springs at the same time. Also I wish to know if there should be a gasket of some sort between original turret mount & Eibach spring centering aluminum tophat disk?

Cheers GW

[Levi_]

Good job, save me some time. It works OK for race style springs ie; ground flat both ends, but overrates normal Skyline configuration by around 15%

Cheers

Gary

Any suggestions for the Javascript version I'm working on?

[Sydneykid]

Any suggestions for the Javascript version I'm working on?

There are few things that I do in the calculations based on experience. That is hard to make black and white, but maybe try these for start;

* You have a "number of coils" input, from which I would subtract a "number of inactive coils" input with a default at say 1.5. That represents the standard R32/33/34 spring configuration.

* Then perhaps a suggestion for 2 inactive coils, if it's a race style spring. That will give a more accurate result.

* Perhaps a warning on paint/powder coat thickness and that all coils are slightly tapered (even as little as 1 mm).

I am not sure how you get over the cold wound versus hot wound spring steel metalurgy differences, perhaps simply ignore it as the diffference is not significant in what most guys will use this for.

Cheers

Gary

[260tech]

Hi Gary, out of interest what spring-rates are the Eibach jobs you supplied me earlier this year for my Stagea

(Edit: found some info here thanks, <http://eibach.com/eibach/img/ers-catalog-2004.pdf> 285/228lb/in plus rear helpers)

& have you come up with an install guide as yet.

Cheers GW

[Levi_]

There are few things that I do in the calculations based on experience. That is hard to make black and white, but maybe try these for start;

* You have a "number of coils" input, from which I would subtract a "number of inactive coils" input with a default at say 1.5. That represents the standard R32/33/34 spring configuration.

* Then perhaps a suggestion for 2 inactive coils, if it's a race style spring. That will give a more accurate result.

* Perhaps a warning on paint/powder coat thickness and that all coils are slightly tapered (even as little as 1 mm).

I am not sure how you get over the cold wound versus hot wound spring steel metalurgy differences, perhaps simply ignore it as the diffference is not significant in what most guys will use this for.

Cheers

Gary

At the moment I'm subtracting 2 coils to get the active number, so maybe have a checkbox thing that says "for skylines" which will modify the 2 in the equation to a 1.5?