Hard suspension

The ride is as described in some of the other posts - crashing over potholes and setting up rattles in the vehicle. The airbags are new dunlop items, the pump is new and the EAS is working properly on height changes etc, so it points at the two changed items the polybushes or the shockers or both. I've been underneath and checked the shockers - they are Britpart units. I've noted that the polybushes are orange in colour, my son can't remember what make they are. My last Range Rover was a '92 Classic which had been converted to coils and had also been polybushed with blue coloured bushes, that ran very well over speedbumps and potholes and was nice and compliant. This car was also OK before it was messed with so I think I will go for shockers first, as that seems the least work for now. Will report on outcome!

alan4693 said:

The ride is as described in some of the other posts - crashing over potholes and setting up rattles in the vehicle. The airbags are new dunlop items, the pump is new and the EAS is working properly on height changes etc, so it points at the two changed items the polybushes or the shockers or both. I've been underneath and checked the shockers - they are Britpart units. I've noted that the polybushes are orange in colour, my son can't remember what make they are. My last Range Rover was a '92 Classic which had been converted to coils and had also been polybushed with blue coloured bushes, that ran very well over speedbumps and potholes and was nice and compliant. This car was also OK before it was messed with so I think I will go for shockers first, as that seems the least work for now. Will report on outcome!

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just make sure you dont use ****part items.

alan4693 said:

The ride is as described in some of the other posts - crashing over potholes and setting up rattles in the vehicle. The airbags are new dunlop items, the pump is new and the EAS is working properly on height changes etc, so it points at the two changed items the polybushes or the shockers or both. I've been underneath and checked the shockers - they are Britpart units. I've noted that the polybushes are orange in colour, my son can't remember what make they are. My last Range Rover was a '92 Classic which had been converted to coils and had also been polybushed with blue coloured bushes, that ran very well over speedbumps and potholes and was nice and compliant. This car was also OK before it was messed with so I think I will go for shockers first, as that seems the least work for now. Will report on outcome!

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Is the ride height set correctly, in the normal position? If it has been set too high the ride will be harsh.

Think so, it goes up quite high when I press the up button and drops down OK to the standard setting, drops OK on Motorway too. The cars on standard wheels and 'Scorpion' tyres inflated to correct pressure. Spoke to my son about it again and he seems to recall being unable to move the shockers (don't know how hard he tried!) though the garage didn't comment on this when they fitted them.

alan4693 said:

Think so, it goes up quite high when I press the up button and drops down OK to the standard setting, drops OK on Motorway too. The cars on standard wheels and 'Scorpion' tyres inflated to correct pressure. Spoke to my son about it again and he seems to recall being unable to move the shockers (don't know how hard he tried!) though the garage didn't comment on this when they fitted them.

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Shockers only damp in one direction, they should be reasonably easy to push in, but difficult to pull out. When they are led on their side in storage sometimes oil runs to where it should not be. They must be exercised several times in the upright position before fitting, to get the oil where it should be. If you are used to driving a car the suspension on a P38 will be noticably stiffer. The polly bush kits are designed for off road or for competition cars where the suspension needs to be taut to prevent body roll on a track. Personally i would not fit them on a road car. A P38 is a lot different than Kevins lowered Corsa.

Modern shocks provide both compression and rebound damping, in some cases one or both modes are user adjustable.

Datatek said:

Modern shocks provide both compression and rebound damping, in some cases one or both modes are user adjustable.

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Yes gas shocks do. All shocks have some compression damping but it is rebound damping that is the most important. We are not talking £100.00 quid shocks here. Gas shocks give some compression resistance and a quicker damped rebound. So basically the suspension resets itself quicker. If you have a shocker that gives too much compression damping you cannot have anything other than a firmer ride. The two way damped type are for vehicles with little suspension travel, as i said Kevin and his lowered Corsa. In my opinion expensive gas shocks are a total waste of time and money on the average road vehicle. As are the polly bush kits. Big bore exhausts and petrol saving devices. Together with K&N filters and blue leds on the wipers Etc,Etc,Etc. Must admit i do have some rather nice blue Zenon side lamp bulbs in mine though.

gemsdad said:

just make sure you dont use ****part items.

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At the risk of attracting a lot of flak from you guys, I'm on Britpart shocks AND bags for over a year and perfectly pleased with ride quality. I did try their polybushes, first set to arrive had some play (between bush and sleeve) so they gave me a new set for free. These fit better but there's no way around the fact that their performance is ****e, the ride was more jittery and... squeaky! Later I changed back to rubber and its all working well together. So, unlike many here I was pleased with the customer service and I can't really complain about their quality given how cheap they are (or were... prices seem to be steeply up this year).

rasheed said:

At the risk of attracting a lot of flak from you guys, I'm on Britpart shocks AND bags for over a year and perfectly pleased with ride quality. I did try their polybushes, first set to arrive had some play (between bush and sleeve) so they gave me a new set for free. These fit better but there's no way around the fact that their performance is ****e, the ride was more jittery and... squeaky! Later I changed back to rubber and its all working well together. So, unlike many here I was pleased with the customer service and I can't really complain about their quality given how cheap they are (or were... prices seem to be steeply up this year).

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I fitted Britpart shocks to my old Disco no problem at all.

I am based in the west of Ireland where many of the roads are potholy! I too find the ride hard with newish bags as I did also with a s2 disco with air. Compared to my first disco on coils which I found wallowed softly through them. My conclusion is that the air suspension should have had a soft setting where it runs at a lower pressure when the going suits. Could this be done? I have looked at settings via faultmate but could not find an air pressure setting I could adjust. Any ideas guys?

mgmayo said:

I am based in the west of Ireland where many of the roads are potholy! I too find the ride hard with newish bags as I did also with a s2 disco with air. Compared to my first disco on coils which I found wallowed softly through them. My conclusion is that the air suspension should have had a soft setting where it runs at a lower pressure when the going suits. Could this be done? I have looked at settings via faultmate but could not find an air pressure setting I could adjust. Any ideas guys?

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The pressure in the bags is directly proportional to the weight of the vehicle, if you want a softer ride fork out on some good quality adjustable shock absorbers

mgmayo said:

I am based in the west of Ireland where many of the roads are potholy! I too find the ride hard with newish bags as I did also with a s2 disco with air. Compared to my first disco on coils which I found wallowed softly through them. My conclusion is that the air suspension should have had a soft setting where it runs at a lower pressure when the going suits. Could this be done? I have looked at settings via faultmate but could not find an air pressure setting I could adjust. Any ideas guys?

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Hi mgmayo,

Good to see another Irish owner around here. What ride height are you running at?

Air springs are a funny old thing, especially when they are designed for adjustable height rather than adjustable spring rate. The pressure the bags run at doesn't change a whole pile with the movement through ride heights. As you pump in more air the surface area it acts on doesn't change much (the top and bottom faces of the airbag) since the volume increases (i.e the car rises). Its not like a car tire where the volume stays pretty much the same and the pressure increase uniformly as you pump in more air. With the RR you have unconstrained-ish movement up so once there is enough air pressure in the bags to get the RR off the bump stops the pressure doesn't change near as much as you might expect through the different height changes.

What does change though is the spring rate when you compress it at each of the different ride heights. Arnott claim that the OE Dunlop bag has a falling rate bag design so that ride is supposed to be more supple at motorway height than standard. They claim their own Gen III bag is a rising rate spring giving better ride at standard height going firmer as you drop down to motorway. Either way it means that the spring rate varies depending on the ride height.

If you are running standard airbags, the first thing I would do is try and calibrate the ride heights and see if that makes a difference. I would then play with altering them up and down a bit to find the ride height that gives you the best ride comfort that suits you.

HTH Cormac

mgmayo said:

I am based in the west of Ireland where many of the roads are potholy! I too find the ride hard with newish bags as I did also with a s2 disco with air. Compared to my first disco on coils which I found wallowed softly through them. My conclusion is that the air suspension should have had a soft setting where it runs at a lower pressure when the going suits. Could this be done? I have looked at settings via faultmate but could not find an air pressure setting I could adjust. Any ideas guys?

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Lower pressure=lower ride height, not exactly what you what over rough stuff. You could try running at m/way height, which would give you slightly softer springing, but risk the unside of the car. Unfortunately standard LR airbags use pistons profiles which actually harden the ride as the car rises through the height ranges. The only way round this is to use Arnott Gen 2 or 3 bags which have revised piston profiles, softening as they rise through their range. If you use Gen 3 bags you can also reset the EAS ride heights to give a good 2" of additional clearance over factory 'high' mode, as well as greater articulation (longer travel dampers also required).

THanks guys, sorry about delay in responding, ye have given me good food for thought. Yes I would be more critical of the ride at the standard height when the speed is lowish on the rough roads. Most of the time I am towing a water tank of about 2ton and dont find the hardness, it's when I have the trailer off I am critical. I have a faultmate and will play with the settings. I will then look ath the shocks.

I got to fiddle with the settings via faultmate today. I set the std ones just higher than the motorway setting. I had to clear a fault that arose as a result. On a test drive it feels good, somewhat softer, did the trick thanks. mg