34 replies to this topic

[Mani]

Standard vxr rates 271 lb/in front 371 lb/in rear checked last week. More than happy on the road. Like anything you get usedto the setup.

[PaulCP]

Surely though it's not just about spring rates though but also the spec of the shocks. My Quantum Blacks are 450lb front springs with 150lb helpers and 550lb rear springs with 250lb helpers and feel much more compliant on the road than my previous set up

Edited by PaulCP, 25 October 2013 - 09:39 PM.

[alexb]

Just to throw a spanner in the works, what happens when you throw progressive springs into the mix as a lot like me have them now.

 

It just means that at every position of the spring you have a different ride frequency. You can't use the normal formulas anymore, but not too difficult to cure that. As long as you know the specs, e.g. are they linear progressive (rate increasing linear with crush). But for me the whole idea is to set the car up according to some guidelines that you can find in any suspension guide, like ride frequence around 2Hz and difference of around 10% front to back. Load transfer distribution about 5% higher at the front than weight distribution (that's where ARB's come in). Average damping ratio 0.5-0.7 with rebound damping about 2-3 times higher than compression damping (that's where dampers come in).

 

All of the above are just guidelines, but still should be good starting points. I just wondered why Lotus, or Vauxhall, went the other way with ride frequency. That's really one of the basic things and I'm shure they have done it for a reason.

[alexb]

Standard vxr rates 271 lb/in front 371 lb/in rear checked last week. More than happy on the road. Like anything you get usedto the setup.

 

You're quite right about getting used to things. That and the amount of things you can vary make the whole suspension thing diffiicult to approach objectively. No harm in trying however. Unless you end up in hedge backwards that is

[jonnyboy]

Can you order Gaz and the like with OEM rated springs?

 

Might be a good alternative now original shocks are hard to come by for those of us who cant stand stupidly hard suspension!

[alexb]

Surely though it's not just about spring rates though but also the spec of the shocks. My Quantum Blacks are 450lb front springs with 150lb helpers and 550lb rear springs with 250lb helpers and feel much more compliant on the road than my previous set up

 

Well, dampers don't figure at all in ride frequency calculations. 'All' they do is damp whatever the springs do. Left to their own devices, the sprung mass and the springs want to go up and down in the resonance frequency forever. That doesn't feel to too good and that's why you have dampers. But you only add them to the fry once you figured out the springs. It's the chapter after the ARB

 

Helper + main spring at the front have got a combined rate of 113lb and at the back 172lb. That for sure should feel very compliant, but aren't they completely crushed at normal ride height?

[nitram38]

Helper springs just take up the slack when the main spring is unloaded which keeps the main spring in place on its seat. Shouldn't be adding or taking away anything from your spring rate.

[alexb]

You're right, tender should be used for a higher rate spring with an intended use in combination with the main spring and helper for a low rate spring intended to just keep the main spring seated. I used the word helper as that was used in the original answer and tbh because I can never remember which word to use for what.

 

Anyway, on our cars and especially in the rear where we don't have a massive amount of travel, tenders should be used and not helpers. Just like mentioned by PaulCP in his set up.

 

 

[Pidgeon]

Can you order Gaz and the like with OEM rated springs?

 

Might be a good alternative now original shocks are hard to come by for those of us who cant stand stupidly hard suspension!

 

Gaz (and all the others I'm aware of) use a standard internal diameter of spring that is available in the correct lengths with 25lb increments in rate from any motorsport source (Demon Thieves) or Gaz themselves.

[ChrisS1]

 

Just to throw a spanner in the works, what happens when you throw progressive springs into the mix as a lot like me have them now.

 

you end up in a hedge backwards ?

 

me-ow

[siztenboots]

 

Can you order Gaz and the like with OEM rated springs?

 

Might be a good alternative now original shocks are hard to come by for those of us who cant stand stupidly hard suspension!

 

Gaz (and all the others I'm aware of) use a standard internal diameter of spring that is available in the correct lengths with 25lb increments in rate from any motorsport source (Demon Thieves) or Gaz themselves.

 

 

2.25" ID front and back on the Nitrons , might be different for some of the slimmer units

[ChrisS1]

 

Just to throw a spanner in the works, what happens when you throw progressive springs into the mix as a lot like me have them now.

 

you end up in a hedge backwards ?

 

me-ow

[siztenboots]

 

 

Just to throw a spanner in the works, what happens when you throw progressive springs into the mix as a lot like me have them now.

 

you end up in a hedge backwards ?

 

me-ow

 

 

must be my clairvoyant powers , how about Turbo owners win this weeks lottery ?  

[pete-r]

Just to share my suspension story... I had a standard NA setup and thought the ride was great and for the road the car was lovely. On track it did pitch a little more than other cars being on R1R rubber, but my car is 99.9% used on road. My rears have been leaking though so it was time to change and I had a steal of a deal on some hardcore quantum blacks. They are completely OTT for road use but they were cheaper than a new set of Zeros and if I start tuning the engine and doing more track days they can go as mental as I need them to go. Problem was they came off a lotus racer with silly springs rates north of 600lb. Eliseparts chatted with me and the mechanic, and I kept pushing softer so we went for 300/425 and the shocks on soft and +2 front/rear. The car was then geo'd against exige s values. The car is sensational in term of comfort and handing. You feel your way around corners now, though with the state of my old shocks anything would be better. Not gone on track with it yet but just on motorway bends and roundabouts you can feel the car change and hold direction is vastly improved. So from my setup I don't think you necessarily need to go very hard, but the moral of the story is probably to get what's matched to your dampers and driving habits (or get silly adjustable dampers).

[P11 COV]

Just sent my Nitrons off for refresh. Gonna get new springs.  Think I'm going to go 500/650  with 250/350 helpers. Probably 70- 80% track driving.  

 

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