Has anyone heard of or seen anything like the Bridgestone Praxis system? It's an air-based susp. system with 3 diff. ride heights built in. :D

http://www.praxissystems.com/product.asp?id=p_main

Interested in your ideas/experiences as this Praxis system is debuting on the WRX! ;)

c'mon you lot, someone must have a constructive thought about this?!?

right, if I don't get a decent reply on this soon, I'm giving up on SN... I have issued a challenge - can anyone answer the call??? :)

BTW, the BMW X-5 uses air susp. What do you say to that?

Hi There,

I also don't understand there apparently is little interest on the airsuspension. If it really does what is says, there is a good chance I will get this. I have an STI7 PPP but for the day to day driving (done 50.000km in 14 months) the STI suspension is too bumpy. On some highways I also get this 'resonance' in the suspension that makes the STI ride like horse. The most important reason I would take the Praxis suspension is that in 'touring mode'it should be much more comfortable (like a standard WRX), and with one push on the switch it goes back to the 'STI set up' in 'sport mode'. I also looked at the TEIN Flex coilover with adjustable settings, but don't think this will provide a much smoother ride than the standard suspension.

Driving the STI 7 as it is makes fun when you drive it for fun. However when I (like this week) drive from my home in Holland into Germany (300km and back) on the bumpy autobahn it is no fun at all. Yes the few high speeds runs are fun (15 minutes at 256km/hr on the guage) but the rest of the ride it is just very uncomfortable. So having a adjsustable suspension could make the STI a perfect car for all conditions.

Looke like we need to wait a few monts before these Praxis air suspensions will be delivered in the US, and will wait a little longer before I will buy it, so there are some more reports from people that have done the installation.

My major worry would be the reliability. There is the compressor, the valve block and the controller, and it is unsure how this all will keep working all the time for 100.000km and more. The added weight should be no issue, you can take the spare tire out, and with the compressor and a foam repair kit you'd be OK. (Cayenne with Airsuspension does this also).

Huffer, I am very glad you found out about this praxis system, and put it to our attention. And it is hard to believe that all STI owners really like the hard suspension on the STI and would not really like to be able to lower the car by 2 inch when on track, and still be able to drive to work with a comfortable car.

sounds interesting, agreed, the idea of push botton adjustable suspension sounds fantastic in theory, price and reliability an issue though! i look forward to seeing how the praxis system works out....

Finally! Some constructive response... :D :D

Well, after doing some more reading about the Praxis system, it's not simply a matter of pushing a button - you still have to turn a knob at each corner of the car, but that's about it.

Turns out Tire Rack.com are already taking orders for the system, and it's looking quite good. :D

"but for the day to day driving (done 50.000km in 14 months) the
STI suspension is too bumpy."

My understanding is that the air suspension doesnt work well at slow speeds - the new jag for example - feels every bump until you get going - small bumps on an imperfect road dont get ironed out - so not sure you'll find it any smoother than the std STI kit...

Subaru themselves make pneumatic ride height adjustable suspension you know. It's on some Legacies...

Rich.

and what a load of tosh it is!!! the amount of air legs and compressor come valve blocks i've had to change the problem is the bags that fill up with air perish then sit the car down on it's bump stops and the valve block gets corroded due to the fact you cant dry the air enough to get all the moisture out so the seals get all gunked up and stick and then it won't blow anything up not even a party balloon!!! believe me stick to standard suspension it's easier and a lot less costly

I have a Praxis suspension a WRX sedan. It comes with an air dryer integral in the system. You can change height while driving with no problem. Load the car up with 4 of your big @$$ed buddies and it maintains the "set" height. Drive to the track, adjust the dampers for the new stiffness, drop the car ... & the struts spring rate is now >400 lb/in.; Touring Ht & damper adjustment has a spring rate at ~160 lb/in & feels very stock.

So Psistar - how you find it day to day, and on the track?
Any comparisons with the normal springs & shocks, and what year sedan do you have?

Cheers

Have to agree with scoobyboy on this,I'm a landrover technician and work on range rover and discovery 2 which have air suspension (disco 2 rear only).The ride qualiy IMO is not as good as coil springs and reliability well forget it.The system comprises of :-

air springs
valve block
compressor
height sensors
drier
ecu
pipe work

there is to much to go wrong and i can't see to much in the way of benefits ,just think when it goes wrong in a couple of years time who's going to fix it for you and how much will it cost,availability of spares etc...

Some older vehicles are having the air suspension removed and being converted to conventional springs.

And by the way bmw nicked the air suspension concept from landrover,if you really want air suspension buy yourself a lorry:)

Cheers for the feedback - is the Praxis system the same as the one used in landrover? From what I've read from publicity material, the Praxis system was designed around the WRX platform (as a quick street/track car). I notice also that the shocks are KYB (Koni?) dampers.

Day to day is no different with the Praxis. I do hear the valve block click occaisionally, but that is it.

Definitely the reliablitly will be less for any system utilizing more components and definitely active components vs. that of a stock conventional system ... but, where's the fun in that?!?

I doubt that this system upgrade woudl be advisable for those driving just a grocery getter. But, for those of us who do like to get out on a track its perfect. Tighten it up for a dry smoooth track, a little softer for one with a few ripples, & maybe really soft for rainy days ... those days are called pass the Vipers, not too mention Beemers & Porsches. Haven't seen any Land Rovers on the track.

As far as the future for maintenance, I'll prolly have to address that also with the race engine I plan on installing this summer. Plan on boosting to 25 psi. Maintenance is maintenance; although Bridgestone is behind the product. A Bridgestone engineer visited me the 1st month I had the system ... not too bad for customer service.

If I can't get parts in a couple of years ... wait a moment, a couple of years?!? Why would I still have *this* car in a couple of years?

I have a '02 sedan e/w VF34 ... TurboXS stage 4, Stoptech BBS (the best mod ever!)

[Edited by PsiStar - 2/2/2004 1:01:07 AM]