SLS Airbag Space Heights

**twr7cx** · 15th February 2013, 02:20 PM

I have noticed that a lot of the spacers being sold for the SLS airbags are not actually 2" tall (despite being sold as such). Generally they seem to be around the 30mm mark. What is the story with this?

I would assume this would result in more air going into the airbag, therefore extending the airbag length (longer than it should be at on-road height) and perhaps also effecting the spring rate - I would think more air would make them firmer - perhaps this change in spring rate was the aim to compensate for the effect on the handling from the suspension lift?

Tombie · 15th February 2013, 02:48 PM

You are thinking very correctly..

Without increasing the rate, the vehicle gets a little squirm up at the back.. The slight increase in pressure and height improves this in light of the COG change

**twr7cx** · 15th February 2013, 03:33 PM

Originally Posted by Tombie

You are thinking very correctly..

Without increasing the rate, the vehicle gets a little squirm up at the back.. The slight increase in pressure and height improves this in light of the COG change

So I guess my next question is therefore, about the standard air bags being extended beyond their design.
I realise that at the on road height, the extra 20mm of extension shouldn't be an issue as the bags are capable of extending further.
But what about at off road height, can the bags handle the extra 20mm of extension?

**biggin** · 15th February 2013, 03:39 PM

Yes, they have so far. And for many others also.

**antond** · 16th February 2013, 07:16 AM

The spring rate increases with the amount of air displaced, and this is mostly affected by the shape of the piston. If you look at the piston at off road height it increases in size towards the top, meaning the spring rate increases when raised.

But to answer your question, the air springs should be able to accommodate 20mm extra from non modified off road height. The raise for off road height is about 40mm so this would be 60mm above standard. I would not push any further than this as there comes a point where increasing pressure does not increase the height and this is where there is a risk of the compressor damaging the air spring.

**antond** · 16th February 2013, 07:19 AM

Btw my spring spacers are 40mm with extended shocks adding 50mm. This adds approx 10mm to the air spring at full extension.

Thread: SLS Airbag Space Heights

Thread Tools