P38A Arnott gen 3 air spring too stiff

Montyjohn said:

I don't fully get how they work, but I don't believe a higher setting results in a higher pressure.
Forcing air into a tank that can't expand or something stretchy like a balloon will increase pressure with more air.
But the suspension air bags are free to enlarge without creating any more pressure.
Assuming the bags aren't over inflated then the only source of load to create the pressure is from the weight of the car which is constant.

I think that's right anyway.

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The Gen 3's use a different piston. When lowered it uses a larger surface area and a smaller one when inflated on the higher suspension modes. I don't know the spring rates or the change you get from high to low ride heights.

To visualise, imagine an inflated ballon, poke it with your finger and it'll still depress quite a bit. Use your palm and it'll have way less effect for the same effort. Let some air out and repeat. In practice it would be like using your palm on the motorway height and your finger on the off road height.

Montyjohn said:

I don't fully get how they work, but I don't believe a higher setting results in a higher pressure.
Forcing air into a tank that can't expand or something stretchy like a balloon will increase pressure with more air.
But the suspension air bags are free to enlarge without creating any more pressure.
Assuming the bags aren't over inflated then the only source of load to create the pressure is from the weight of the car which is constant.

I think that's right anyway.

Click to expand...

There is little or no expansion in the bags, they can only really extend or contract linearly. The weight is not constant since upward deflection of the axle will compress the spring and vice versa as will articulation which causes weight transfer.

I had Dunlop on mine originally but went for Arnott Gen 2 because I was so i pressed at the condition of Dopey's after 10 years. No difference in ride from Dunlops. Unfortunately the caps kept getting dislodged which was a bit odd. Fortunately I kept the Dunlops so just swapped them back (never throw anything away until you're certain it is of no further use). Arnott gave me gen 3 after the second or third gen 2 spring failed and they were not only a noticeably better ride but also very clearly superior build quality. A real nice piece of kit, although I don't like the type of air-line connector they use. I tend to leave it at Standard height but I'm rarely on A-roads.

Datatek said:

The weight is not constant since upward deflection of the axle will compress the spring and vice versa as will articulation which causes weight transfer.

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The car weighs the same, the transfer is the same give or take depending on speed during normal use.

Datatek said:

There is little or no expansion in the bags, they can only really extend or contract linearly.

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So when does pressure affect height, when the weight of the car doesn’t change?

Had this conversation before.

J

marjon said:

The car weighs the same, the transfer is the same give or take depending on speed during normal use.




So when does pressure affect height, when the weight of the car doesn’t change?

Had this conversation before.

J

Click to expand...

So you have not seen the effects of weight transfer.

Datatek said:

So you have not seen the effects of weight transfer.

Click to expand...

Yep.

J