Air Suspension Vs. Coilovers

Kinja'd!!! "Bacon" (bacon117)
11/12/2013 at 11:26 • Filed to: None

Kinja'd!!!0 Kinja'd!!! 28

Here is an interesting look comparing the performance of specifically engineered air suspension, vs. a standard aftermarket coilover setup. Very interesting!

http://www.airliftperformance.com/airvscoilover/


DISCUSSION (28)


Kinja'd!!! YSI-what can brown do for you > Bacon
11/12/2013 at 11:28

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Now, I am not saying it is biased. . . but it totally is. Plus for the price of the air suspension you could get some seriously good coilovers.


Kinja'd!!! Victorious Secret > Bacon
11/12/2013 at 11:32

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For what you need to spend on a air system you can get some of the best coilovers money could buy, not the fairest test.


Kinja'd!!! GhostZ > Bacon
11/12/2013 at 11:33

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I would think that static lowering will, universally, make the car handle a little worse, unless you both lower and stiffen the spring rate. I didn't watch the video, but I would imagine bad coilovers would universally be worse than a decent air suspension. But I also think that a racing coilover setup would be better than the best air suspension.

I think this would be best looked at as "how can you drop your car to silly levels without ruining performance" not "how much extra performance can a drop get you". I would think that anyone who actually cares about sheer cornering speed should be going for better tires, sway bars, differentials, bushings, etc. long before deciding between coils or air suspension.

Air suspension gets a bad rap though. It's got its place, and setups now are way better than they used to be.


Kinja'd!!! E30Joe drives a Subaru > YSI-what can brown do for you
11/12/2013 at 11:33

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At this point in my life I'd rather have air. But of course not on a track rat. Nothing beats a set of good coils for the E30. But on my next car, which I won't be tracking, I would love a good air ride setup. Nothing like having the option to scrape frame or be at stock ride height at the push of a button.


Kinja'd!!! desertdog5051 > Bacon
11/12/2013 at 11:35

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Of course it is biased. The advantage that air has, though is adjustability. You can go as low as needed and still come back up for normal driving.


Kinja'd!!! Bacon > Victorious Secret
11/12/2013 at 11:35

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What are you getting with those coilovers? A spring is a spring, really, whether it's air or not. The point of this is that air provides the performance of coilovers, but adjustability at the push of a button.


Kinja'd!!! Paul, Man of Mustangs > Bacon
11/12/2013 at 11:37

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Most of the money in coilovers goes into the shock valving, which is the most important part of the system. So, for the money you save on compressors and air systems, you could have a very good shock, suck as a Koni or Varishock, or maybe even Ohlins.


Kinja'd!!! Hermann > YSI-what can brown do for you
11/12/2013 at 11:38

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Precisely.

Even if this data isn't fake, I could easily - for example - bias a race to make a Fiat 500 outrun a M5. Just put both in a tight Kart track.

Not to mention the price of the air suspension + installation (which will require a lot of modifications to the car).


Kinja'd!!! Bacon > GhostZ
11/12/2013 at 11:38

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A good friend of mine is in the video, and that is basically what he is saying. A properly designed air suspension can yield as good as, if not better, performance than a quality coil over. This isn't the old style "bags" just made for going up and down, it's actually tailored to each vehicle.


Kinja'd!!! CKeffer > Bacon
11/12/2013 at 11:38

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While I don't doubt that their Air systems are good and give a nice balance of comfort and perfoemance, they don't say what brad of coilovers they used for the tests nor do they say anything about setting up the damping rates properly. If they used a set of coilovers from a company like BC and just threw them on without tuning the damping rates then I'm not at all surprised that the air system won, but I have the feeling that if you put them up against a system from someone like Ohlins and had that system set up properly the results would be quite different.


Kinja'd!!! Paul, Man of Mustangs > Bacon
11/12/2013 at 11:38

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You get fucking awesome double-adjustable shocks. Sure, ride height isn't instantly adjustable, but for the same price, you can fine-tune your handling even more than with a similarly priced air system.


Kinja'd!!! Squid > Bacon
11/12/2013 at 11:39

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Ok, if they released which coilovers they were testing against, along with the damper settings used and spring rates, this may hold some validity. I think for a pure performance application air just doesn't work. The weight penalty is too much for a serious racer application, but for a weekend warrior it may be livable if you like to be able to slam the car while parking. Don't get me wrong, I am a fan of air suspension, just not for a race application, a dedicated set of springs and dampers should out perform an aftermarket set of air springs.

Really this comparison is too biased to be of any use. I do however like the fact that they state they tested each suspension within 3 hours of each other.


Kinja'd!!! Bacon > Squid
11/12/2013 at 11:42

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It's geared toward the track day or autocross enthusiast. At the push of a button, you have a track setup, or a street setup.


Kinja'd!!! roflcopter > GhostZ
11/12/2013 at 11:43

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This is what most people don't realize... I have so many friends, even ones that are decent at AutoX and the such, that believe that lower is always better. What you gain from that extra 1-1.5in lower CG you lose 10 to 1 when your suspension geometry starts going all wacky. Almost all newer cars, especially ones with good suspension from the factory, will incur a decent bit of bumpsteer and unpredictable camber/caster changes during cornering when lowered. Unless you plan on doing your research and upgrading all that is necessary to get the suspension where you want it(camber/caster plates, moving mounting locations, lowering links, whatever else is needed) going lower than -.5in or so will almost invariably cause the car to handle worse. You might feel faster, those stiffer springs might make the car roll less, the sways might balance it out a bit, but you WILL be slower through a corner.


Kinja'd!!! RamblinRover Luxury-Yacht > Bacon
11/12/2013 at 11:44

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I am Andrew Ryan(er, Ramblin Rover), and I'm here to ask you a question. Is a man not entitled to the comfort of his low? 'No', says the man of the air suspension, ' your low must sag'. 'No', says the man of the coilover, 'your low must be stiff and permanent'. 'No', says the man in the hoopty with cut stock suspension, 'you must hit your bump stops allatime'.

I rejected those answers; instead, I chose something different. I chose the impossible. I chose... Rapture. And by Rapture I mean I'm fitting the Ranchero with bi-directional hydraulics over close to stock-rate springs.

Like Rapture, high pressure leaks are gonna be a bitch.


Kinja'd!!! Bacon > Paul, Man of Mustangs
11/12/2013 at 11:46

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You're talking about kits that are $10k or more, and specifically designed for racing. These are 4k with the digital controller that determines how much air to put to each corner automatically, and are geared toward track day or autocross enthusiast. The dampers are also adjustable in the air kit. One thing you have to be careful, is that a lot of dampers say they are adjustable, but if you put them on a shock dyno, they have very little actual range of adjustment.


Kinja'd!!! Squid > Bacon
11/12/2013 at 11:46

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Holy shit, just looked up the cost of this system. There is no way that this system would keep up with a set of Ohlins. This system is in the same price range of the Ohlins set up with invalidates all of their claims.


Kinja'd!!! Paul, Man of Mustangs > Bacon
11/12/2013 at 11:50

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Konis are about $2000 for a set. Ohlins, yeah, those are expensive. But many adjustable coilovers are actually pretty adjustable. I had a set of Tokicos that went from stock-stiffness plush to feeling like I doubled the spring stiffness.


Kinja'd!!! Bacon > Paul, Man of Mustangs
11/12/2013 at 11:53

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I don't recall what dampers are actually in the Air Lift kit. But your user name implies you like mustangs. You might like this video: http://www.speedhunters.com/2013/10/introd…


Kinja'd!!! Paul, Man of Mustangs > GhostZ
11/12/2013 at 11:55

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All things being equal, lower is better, provided you're not bouncing off the pavement. A lower center of gravity makes for reduced weight transfer, so the tires are used more efficiently. That being said, if it's lowered, it must be stiffened to prevent the aforementioned pavement bouncing. And if you have a strut car, it'll need lowering ball joints to keep the roll center above ground and the camber curve in check. For an unequal length wishbone system (SLA), you'll need a drop spindle.


Kinja'd!!! Squid > Bacon
11/12/2013 at 11:58

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Give me a set of Ohlins for the price of this set up and I'd be happier.


Kinja'd!!! sloPro > Bacon
11/12/2013 at 12:10

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Mk6 Golf R weighs 3470 lbs!!!! and with no passenger. wtf?!

brz weighs 2764 lbs, again dam, my mazdaspeed protege with 2 extra doors, and subs in the trunk weighs 2750.

also the mustang weighs in at 3650, which is only 180 pounds heavier than the R (which is only like a tall passenger riding along) and yet both the "professional" driver and the voice over call it a "big, heavy" car. I cal bias!

Anyhow fantastic soundtrack for the whole video, reminds me the old PS game Vigilante 8.


Kinja'd!!! Casper > Bacon
11/12/2013 at 12:12

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Ummm no. The durability and precision of a specialized alloy/composite sprint has progression/response that air has a very hard time matching. You are building around a flawed material: air. It's comprised of varying elements or varying densities that respond differently moment to moment and changes drastically with heat. Not even getting into the increased options for shock systems.


Kinja'd!!! Paul, Man of Mustangs > Bacon
11/12/2013 at 12:13

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Just looked up prices for the Ohlins kits. They seem to average $2400. A Koni system costs around $1600. If you want a $10,000 coilover kit, then you're looking at Penske 4-way adjustable, which adjust the damping curve shape in bounce and rebound, in addition to basic rate. I'd go with the Konis (and I am, in real life) because they're valved good to start with, and I can use the money I save by putting in better control arms and bushings, as well as geometry correction.


Kinja'd!!! Casper > Bacon
11/12/2013 at 12:15

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Air systems have and will always have a limitation: the air. Air is not a great gas for using in any precision systems because of the variance in quality, reactions to heat and pressure, etc. Not to mention you are still operating on balloons that lack natural structural consistency. The durability and consistency just doesn't exist for a valid comparison.

Not to mention the increased weight and complexity. Air systems fill a specific niche, and that niche is not the same as performance coil systems.


Kinja'd!!! BiTurbo228 - Dr Frankenstein of Spitfires > Bacon
11/12/2013 at 12:20

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I wonder how they both compare to a good stock setup...


Kinja'd!!! rabidpenguin > RamblinRover Luxury-Yacht
11/12/2013 at 12:36

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Would you kindly post pictures of this awesome-ness?


Kinja'd!!! RamblinRover Luxury-Yacht > rabidpenguin
11/12/2013 at 12:46

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I definitely will when I've got it built. I plan to get a lot of mileage out of the ludicrous distance to the lower control arm from the top of the shock tower in front and with the planned rear suspension swap, I'll be building a bell-crank setup cross-mounted to the suspension frame. The nice trick with bi-directional cylinders is that you can lift wheels as well as push them down, and reserve capacity doesn't have to be as much as single-direction units. I'll probably use a PS pump with 4x steering column valving to keep costs down, as I won't need PS and the engine's set up for it.

Sounds downright French, don't it?