Shock absorbers/ springs for best ride quality

[JAL73]

I am considering upgrading the Bilsteins on my 2020 420R SV in search of refining the way my car handles bumps and poor road surfaces.
My car can be quite crashy over bad surfaces and prone to the rear skipping over bumps at high speed, Im wondering whether this is just something inherent in such a light weight car or whether its possible to achieve a really significant improvement in ride quality with better suspension components and a proper set up.

It seems the price of suspension upgrades plus geo/flat floor starts around £2k and goes up to about £8k which is a serious chunk of money.
Curious to know what other owners have upgraded to and whether they think its worth the money? Appreciate its a quite a subjective topic.

Please note im more interested in improving compliancy and road manners rather than shaving seconds off lap times! 

[Mrb00ns]

Have you had it set up for you in current form? It might improve things significantly without the spend. 
I don’t think ride comfort is really a thing in 7s (although I don’t personally mind the ‘connection’ with the road). Car shouldn’t really be skipping unless you are giving it the beans. 

[Colin_T]

I’d speak to Simon at meteor motorsport

 

[Shortshift]

David

You could do a lot worse than by contacting Nitron direct and asking for a set of their NTR-1 one-way adjustable dampers and springs with the settings* that they developed on my R500.  After false dawns elsewhere, I now have a car with great compliancy for on-road use (at one end of the adjustability range) which are absolutely fine for my type of trackday driving (when set to the other end of adjustability).  The car has been transformed.

I'd also add the general caution that, from my research and experience, many aftermarket specs for Caterham springs and dampers seem to be based on extracting ultimate performance.  Great for on-track duties but wearing and uncomfortable on road.  I feel I have finally achieved that elusive 'best of both worlds' set-up.

James

PS: edited to remove any reference to these being the "James Batchelor settings"... 😅

Edited April 16 by Shortshift

[SamC]

You know you’ve made it when you’ve had damper settings named after you James!

[Shortshift]

I might regret posting that, then!  But how else to communicate what it was that they did? 

OK - better to ask for the settings that they developed for me...

I'm going to edit my original post, now, which will make a nonsense of your follow-up post Sam - but I can't stand the blushing!

James

[SM25T]

On my SV, I replaced all 4 dampers and springs for less than £600 .... supplied by ProComp Motorsport, using dampers from Protech which were revalved by ProComp to suit the Caterham. Work really well for my road use.

[JP]

@SM25T - Have you had any issues with the shoulder of the rear damper fouling the De Dion tube (using the lower De Dion mount)?

[SM25T]

6 minutes ago, JP said:

@SM25T - Have you had any issues with the shoulder of the rear damper fouling the De Dion tube (using the lower De Dion mount)?

Not at all. On the fronts I needed a 25mm longer top eye to avoid top spring cup fouling a bracket.

[Wrightpayne]

Tyre sizes, particularly profile also affect comfort. 13s tend to have more sidewall than 15s so ride a bit softer.

[Miker7]

4 hours ago, SM25T said:

On my SV, I replaced all 4 dampers and springs for less than £600 .... supplied by ProComp Motorsport, using dampers from Protech which were revalved by ProComp to suit the Caterham. Work really well for my road use.

I've been thinking of going to Darren for a quote, when did you get them from procomp?

[mph]

13 hours ago, JAL73 said:

I am considering upgrading the Bilsteins on my 2020 420R SV in search of refining the way my car handles bumps and poor road surfaces.
My car can be quite crashy over bad surfaces and prone to the rear skipping over bumps at high speed

Please note im more interested in improving compliancy and road manners rather than shaving seconds off lap times! 

Are you on 15" or 13" wheels?

If the former, then the answer is swapping to the latter will vastly improve things. Everyone said that when I bought my car three years ago, and I took it with a pinch of salt. Until I made the swap and couldn't believe the difference 😂 

 

[JAL73]

I’m already on 13” Apollos with Avon ZZS tyres….! 

What is it about the standard 420R suspension that people think is inferior to the various available upgrades out there for compliance on the road?

Is it the Bilstein compression or rebound is too slow or the springs are too stiff? Apologies if that’s an over simplistic question but i was just wondering if its the damper or the spring that contributes most to peoples dissatisfaction with the standard Bilstein components.  

[Graham Hutton]

I had Simon at Meteor sort me out with some CORE 1 way adjustables with softer springs and digressive pistons and it is brilliant on the road and trackways. BUT whilst this made a decent improvement over my original Bilsteins, the first proper flat floor setup that I did after I had driven it for a couple of months completely transformed things. It was spectacularly better, more compliant, less skittish, less bump steer etc etc. So if you haven't had it setup like that first, I would strongly advise doing so before deciding whether to spend out on new kit.

[SM25T]

6 hours ago, Miker7 said:

I've been thinking of going to Darren for a quote, when did you get them from procomp?

It was a few years ago. Maybe 2017 ?

[SM25T]

It was indeed late 2017

[JP]

I got mine last year - straight from ProTech as they come - about the same price £600 for 4.

[Golf Juliet Tango]

Getting the basic set up correct is the starting point. If you haven't done that then get it done.

If you remain dissatisfied, then look at spending more money. 

 

[2cv7]

Take all the anti roll bars off and try that for a day or 2.

[lapsedtheorist]

I’d like to add my tuppenceworth to the topic of having a proper flat floor / chassis set up done… I had similar experiences to you @JAL73 then had this tuning done by @Gemzoe and it’s really transformed the car. Sure, there’s more that probably can be done, but a chassis set up doesn’t have to be to “motorsport” settings in order to provide tangible benefits!

[SM25T]

1 hour ago, 2cv7 said:

Take all the anti roll bars off and try that for a day or 2.

Certainly removing my rear ARB transformed cornering on bumpy roads. Took it off years ago and it stayed off.

[JAL73]

i took off my rear ARB and it did seem to improve things a bit.
i only did the rear cos thats where poor road surfaces seem present the problems but i havent tried the front ARB - would removing the front improve ride comfort much?

Has anyone tracked a 420R with all ARBs removed? I reinstalled my rear ARB cos thought it would understeer a lot on track without it but i really dont know what im doing.

Also, for those that have removed all ARBs - did you then do a flat floor chasis set up after on standard Bilsteins and get nice results?

[JP]

Just to go back to my comment about the close proximity of the ProTechs to the DeDion tube, the area affected is the upper De Dion mounting boss - if you have one.  If you don't I doubt there would be an issue.  I've improved the position with new spacers, but it is yet to have a FF set up following my rebuild and when it does, it may be more sensible to use the upper shock mounts.  I've just taped the area with masking tape so I can check for witness marks after a short drive. Here are 2 pics of the situation:

[Ainsley]

From my experience racing motorbikes off road, I learned the following, which probably relates to the car.  (Ignore me if you already know all this)

Basically the spring just holds the car up.  Hopefully that's correct and the car doesn't sag too much, you can measure its sag by seeing how much the spring compresses when you lower the car back onto the ground after being jacked up and there being no weight on it.  There should be some sag, I dont know how much, but someone will know what is best for the weight of the car.  The wheels need to be able to extend down into a hole without the car falling into it.

If the spring rate is too hard it wont allow the suspension to work, too soft and it will sit too low.  Its the rebound / compression that affect the rate of it squashing or extending.

Remember the spring rate is linear, it wont change if you wind the ride height up or down.  Only air shocks exhibit progressive rates, or shocks with two springs.

The rebound affects the damper extending back after being compressed, the compression affects the way it compresses.

You want it to rebound fast enough to extend the spring back to its natural position, but not so fast it skips up off the bumps. If it feels like its crashing, it could be the rebound is not fast enough and the spring is being squashed by each bump and not extending back again fast enough to absorb the next bump.

When I raced over very bumpy terrain often speeding up the rate of rebound actually softened the ride as the suspension stopped being compressed.  Messing about with compression made much less difference.  But it took ages sessioning one track to dial it in, making tiny adjustments and noting the affect.  You have to bracket the adjustments and narrow it down from the extremes to get it right.  You would get it perfect for that track only to find it was not perfect for a different terrain.

You end up with a compromise whatever you do.  Also dont forget a few psi in the tyres makes a massive difference.

 

[150SV]

Jal, I have a 150Sv on Billies, has been FF by DPR and is on 13s….

 

i feel very similar , in that I am not happy with the compliance of the ride…
 

I have spoken to all the suspension specialists and am still confused as it’s not something I know enough about.

i di feel the car is to “stiff”, and I believe over sprung and undwr damped…..but as I’m no expert, I may be talking bobbins.

as you say, on the crappy roads we have today, the car feels uncompliant and sketchy over bumps etc when starting to push on.

i have an offer to drive an SV with similar power and Core1 setup, but it needs to stop raining first….