rdboxster

Hey @chasse what are the last 2 pictures of? Good info, thanks for posting. Be interesting to see the new setup in detail.

chassis

Cutaway views of the air springs showing two valves per spring for the three chamber system.

Searcher356

So is that the system they just replaced?

chassis

Yes, the images are from the 9Y0.1 launch tech presentations.

gloryrd

It looks like the new air suspension results in less height variation. On the base 9Y0.2 model air goes from 7.5 normal to 9.3 high terrain (1.8"). The 9Y0.1 variation is from 7.4 normal to 9.6 high terrain (2.2"). The steel suspension of the 9Y0.2 is 8.3", 0.1 inch higher than the 9Y0.1, despite the tires being 1" larger in diameter. I bet that the 31" diameter tires wasn't an upgrade. It was needed to compensate for the lack of height variation found in the new air suspension, as well as both air and steel having a lower suspension profile.

It would have been damaging to off-road cred if the Cayenne air suspension lost 1.3" in ground clearance at High. And so we get 31" tires.

For you folks interested in track performance from larger wheels, it also means that the new 22 inch wheels have as much sidewall as the previous 21 inch wheels.

MaxLTV

Except it is an order of magnitude easier to raise the suspension height than to accommodate larger wheels, so this theory does not add up. BTW, Huracan came with this tire size from the outset, so now Cayenne caught up. It's a good change - it looks nice and makes Cayenne less likely to leave you stranded due to low-profile tires crapping out from a small pothole (which happened to me twice in 4 years on the current model).

The reduction in the range of the air suspension adjustment is unfortunate. Hopefully, the offroad mode will be available at higher speeds, though. With the current generation, the problem is that it drops from offroad mode as soon as you accelerate even a little, and you have to manually raise it again when slowing down for another rut in the road. Driving on rutty dirt roads it gets annoying quickly.

Also, surprisingly, approach/departure and break-over angles are actually slightly improved in the updated version - only by 0.1-0.2 of a degree, which is not a meaningful improvement, but based or reduced high mode ride height I'd expect them to be smaller rather than same or even very slightly better.

gloryrd

You prolly have more experience driving off-road than me. But maybe the 9Y0.1 Cayenne isn't designed for your driving habits? I don't believe it totally drops from off-road mode. It's just not designed for driving over 25 mph in Rock Mode, or 75 mpg in the other off-road modes. So it lowers itself. Probably designed like that for safety reasons. I'm good with that.

From a @Schnave post:

chassis

Thanks for the solid suspension comments @gloryrd and @MaxLTV . Have either of you seen diagrams, cutaway photos or performance charts (spring rates, suspension travel) for the new 2-chamber system?

Reading through the years of Porsche media literature, 3-chamber has been twice pointed to by Porsche as a better system than either single-chamber or dual-chamber. Now Porsche with 9Y0.2 is going backwards to 2-chamber.

MaxLTV

I know nothing about the new 2-chamber system besides what was in the press release. I'm very curious because I do drive on dirt roads. But chances are that it's not the same as any previous two-chambers. So it's hard to say if it's better or worse - could go in either direction. I hope it's an improvement. Fewer chambers does not necessarily mean anything is worse.

The three-chamber was definitely and improvement compared to one chamber, both in terms of comfort and robustness. The old 1-chamber was very loud, slow to adjust, and tended to have stuck valves and burn out the compressor. The new one does not seem to have these issues, at least yet. My E3 Turbo is at the mileage where my 958 air suspension started having issues, but this new one is fine so far. It's a sample of one, of course, but rennlist does not have as many complaints as the old one did either.

Ron.s

I agree…the 2 chamber system with rebound and compression damping will give a better ride and will cost more. The manufacturing cost might be near equal but the R&D to develope and tune the new two chamber system will be an added cost. We went through this with shock absorbers with recreational vehicles. The ability to tune rebound added to tuning compression allows a wider range of comfort setting and is probably at least equal in performance tune. This rebound tuning can be done electronically almost instantaneously. When Fox developed a similar shock for the Polaris RZR they cost a lot more to buy.
IMO, Porsche did not make the change to save money.

MaxLTV

Yes, it drops from the Terrain level to High level at 25MPH, and Terrain mode is sometimes necessary on rutted roads just to not scrape. But at the same time, it's frustrating to crawl at 25MPH on a road that's otherwise good enough for 50MPH+ to avoid the car dropping down and the bottom scraping the middle between the tracks. If the highest mode on the new one can be sustained at speeds higher than 25MPH, for me that would be enough to compensate for it being lower compared to 9Y0.1.

gloryrd

Does your E3 Turbo have PDCC? If so, does it help? I haven't driven my Cayenne off-road yet (got it two weeks ago), but the PDCC seems to dampen dips that are only on one-side of the road.

chassis

Regarding comments on joince and rebound control - let’s be clear.

“chambers”, whether 1, 2 or 3 relate to the air springs only. Not shocks.

“jounce” and “rebound” control relate to shocks only. No springs. “Chambers” bear no relevance here.

“PASM” is a shock absorber technology. Not springs.

I see in this thread some of these concepts may not be fully understood and are being exchanged for each other.

rdboxster

Maybe using a 3 chamber air spring with a 1 valve shock is more challenging to get the ride characteristics they are after than a 2 valve shock and 2 chamber spring. Porsche knows suspensions so I doubt this is a step backwards. Plus they have better control with the steel spring suspensions.

Ron.s

Sloppy on my part using the term shock for an air shock system. Here I fixed it.
https://rennlist.com/forums/cayenne-...l#post18768978