My friends @ N1 Concepts went 1:53 @ buttonwillow on AirRex with their s2000 i believe the first time out with the car.

I wasnt ignoring your post man, i was just on the go and will be sending you a pm now ;)

Calculating the spring rate of an air bag is much harder than calculating the spring rate of a typical metal coil spring. Spring rate is defined as the amount weight (typically in lbs) needed to compress a spring one inch. Typically spring rates are calculated using the equation:

k = Gd^4/8nD^3

in this equation:

k = spring constant, pounds of load per inch of deflection
G = modulus of rigidity
n = number of active spring coils
D = wire diameter or coil diameter - measured in inches

Because we cannot plug in raw numerical values for air springs, it becomes increasingly harder to figure out the exact spring rate. Furthermore in the world of air springs, both pressure and volume need to be taken into consideration when trying to calculate spring rate - again, it's not as easy as it would be with a set of coil springs.

There are a two things that are certain more often than not and they are: larger bags will lift more weight but have a lower spring rate and smaller bags will not be able to support as much load but will have a higher spring rate. Spring rate with regard to air ride is definitely a function of bag pressure and volume. Another variable that has to be taken into consideration is the material used in bag construction. The thicker the material, the more weight the bag will support and the less pressure it will need to lift the vehicle. It's very tough to calculate the exact spring rate of air springs because there are (in a sense) too many unknowns. Without breaking out paper and an abacus, you could always set your car at maximum height and consistently add weight until the vehicle drops one inch and do the same at ride height. This will show you that spring rate will vary dependent upon pressure and not just volume. It's a pretty 'raw' method of figuring out the spring rate, but it should give you a general idea of the spring rate of your air springs.

off topic, what spolier is on the red BRZ?

think about this, you're paying 3k+ for BC struts with BC dampeners.

does it work? surely. but if you want the best handling car, you really wont beat a dedicated coilover.

bags will be good for the casual tracker, as they do perform decent.

i've also seen the bad side of it, broken lines (car drops out from under you) leaks from improper installation, etc etc. now obviously this doesn't apply if you install it correctly but with air, there is always that slight chance of something going wrong, because if you pop a line god forbid, you're done if you're doing any kind of spirited driving.


with that said, there is a place for bags and they do work and when setup right they ride great, you just need to decide what you want.

you've heard both sides of the story now make up your own mind, but theres a reason no one who is a die hard track rat uses bags, its just not the best option for that. its a good middle ground if you want to be low and have a car that can make it around city streets, but realistically, its two different realms of suspension. apples to oranges here.

i really dont think that happened.

Referring to [ame="http://vimeo.com/93260756"]this[/ame] perhaps?

I agree this about 90% of what you've said and you've really hit the nail on the head.

Air ride was never meant to be a direct replacement for coilovers, it was meant to be a respectable alternative. As AirLift has shown throughout their videos, marketing, etc. air suspension can perform and it can withstand the abuse on the track.

The video seen here: https://vimeo.com/78528697 is a comparison between coils and air suspension. What most people don't know is that all the cars were equipped with KW V2 coilovers. While many say the test was skewed, it was actually pretty fair.

At the end of the day, air suspension will never be coilovers, that's just a fact. However, air suspension is a happy medium for those seeking both performance and comfort from their suspension.

Hey Buddy, didn't know you were on this forum, I posted that video earlier in the thread. :D

Hey Max :thumbup:

looks like youre right. they were still faster before when they coil springs. i guess sponsorship is a tricky thing.

I don't think anyone doubts that...I think it was more along the lines of that it is still capable of running a very respectable time.

It's really kind of useless, Using a coilover that costs half what airlift does to the end user?
Would of liked to see them put it up against some MCA reds or golds, Ohlins.

so, what you're saying is that KW V2's are not a good coilover?