Air Suspension Questions
08-11-2006 | 12:06 PM
#41
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From: San Bernardino, CA
Originally Posted by GTNPU Z
Wow! Quick...someone jump on these to test them out! 
"I just wanted to email you personally regarding the F.B.S.S Kit. I purchased it through DH Built here on Oahu... I just wanted to let you guys know that i am really pleased with the kit... Rides like a champ still... I used my HKS coilover struts... Ride doesnt really feel any different from when the springs were on...
Regards,
Jermyn D"
08-11-2006 | 03:24 PM
#45
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From: CaCdis Ln
Originally Posted by universalAirSus
Yes we do have for the LS430. However its not as "easy" of an install. There is some modifications to the struts inorder to install. If you have the coil-overs it would be alot easier (dont have to cut off the stock spring pearch).
We havn't tested on the Stance, However if the pressure tube (large part of the shock) is 2.14" or smaller the bag will slide over it.
We havn't tested on the Stance, However if the pressure tube (large part of the shock) is 2.14" or smaller the bag will slide over it.
as far as the Stance goes....imma measure it when i get home!
08-11-2006 | 05:29 PM
#46
interesting - your product certainly has a place, but I do have a problem with marketing this as a performance suspension. It is misleading at best. And please forgive and enlighten me if I'm misunderstanding your products capabilities.
the weight gain on the components at the wheel and the weight of the compressor in the trunk is just the beginning.
To say that "virtually identical to the coil" and "at that height you will now be at the same spring rate on the bag as the coil would be" seems just plain incorrect. There are MANY different spring rates available. How can you say the rate would be the same as ALL the coils available. Unless with your product you can adjust the static spring rate at a given spring length that is independent of the ride height, then you cannot possibly be "identical" to every coil.
While on that point. What is the equivalent spring rate in lb/in of the bags, initial rate to final rate? A wide progressive rate change would make the car wildly unpredictable in a performance application (ie. the track).
Yes, progressive springs can be used in performance applications, but ONLY in very specific applications (for example in one particular track) - I suspect this is what your Japan Team is doing. However, for variety of applications, linear springs are preferred, because they will behave consistently no matter what the conditions.
Similiarly saying that it will work with stock and ALL other dampers seems odd. Dampers are engineered to dampen specific rates. To say that a damper designed to dampen one rate will be applicable to all rates is just wrong.
my thoughts - if you want to slam your car to the weeds, or have ride height adjustability on the fly - this is your product.
no disrespect to you, just the marketing. again, please enlighten me if I'm misunderstanding your product.
pp
the weight gain on the components at the wheel and the weight of the compressor in the trunk is just the beginning.
To say that "virtually identical to the coil" and "at that height you will now be at the same spring rate on the bag as the coil would be" seems just plain incorrect. There are MANY different spring rates available. How can you say the rate would be the same as ALL the coils available. Unless with your product you can adjust the static spring rate at a given spring length that is independent of the ride height, then you cannot possibly be "identical" to every coil.
While on that point. What is the equivalent spring rate in lb/in of the bags, initial rate to final rate? A wide progressive rate change would make the car wildly unpredictable in a performance application (ie. the track).
Yes, progressive springs can be used in performance applications, but ONLY in very specific applications (for example in one particular track) - I suspect this is what your Japan Team is doing. However, for variety of applications, linear springs are preferred, because they will behave consistently no matter what the conditions.
Similiarly saying that it will work with stock and ALL other dampers seems odd. Dampers are engineered to dampen specific rates. To say that a damper designed to dampen one rate will be applicable to all rates is just wrong.
my thoughts - if you want to slam your car to the weeds, or have ride height adjustability on the fly - this is your product.
no disrespect to you, just the marketing. again, please enlighten me if I'm misunderstanding your product.
pp
08-14-2006 | 10:32 AM
#47
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From: San Bernardino, CA
Originally Posted by TUNERZ33
How much for the kit and Dakota Digital Unit + installation?
The dakota digital controller with auto lift will be 3866.15 installed after tax.
08-14-2006 | 10:35 AM
#48
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From: San Bernardino, CA
Originally Posted by palepony
interesting - your product certainly has a place, but I do have a problem with marketing this as a performance suspension. It is misleading at best. And please forgive and enlighten me if I'm misunderstanding your products capabilities.
the weight gain on the components at the wheel and the weight of the compressor in the trunk is just the beginning.
To say that "virtually identical to the coil" and "at that height you will now be at the same spring rate on the bag as the coil would be" seems just plain incorrect. There are MANY different spring rates available. How can you say the rate would be the same as ALL the coils available. Unless with your product you can adjust the static spring rate at a given spring length that is independent of the ride height, then you cannot possibly be "identical" to every coil.
While on that point. What is the equivalent spring rate in lb/in of the bags, initial rate to final rate? A wide progressive rate change would make the car wildly unpredictable in a performance application (ie. the track).
Yes, progressive springs can be used in performance applications, but ONLY in very specific applications (for example in one particular track) - I suspect this is what your Japan Team is doing. However, for variety of applications, linear springs are preferred, because they will behave consistently no matter what the conditions.
Similiarly saying that it will work with stock and ALL other dampers seems odd. Dampers are engineered to dampen specific rates. To say that a damper designed to dampen one rate will be applicable to all rates is just wrong.
my thoughts - if you want to slam your car to the weeds, or have ride height adjustability on the fly - this is your product.
no disrespect to you, just the marketing. again, please enlighten me if I'm misunderstanding your product.
pp
the weight gain on the components at the wheel and the weight of the compressor in the trunk is just the beginning.
To say that "virtually identical to the coil" and "at that height you will now be at the same spring rate on the bag as the coil would be" seems just plain incorrect. There are MANY different spring rates available. How can you say the rate would be the same as ALL the coils available. Unless with your product you can adjust the static spring rate at a given spring length that is independent of the ride height, then you cannot possibly be "identical" to every coil.
While on that point. What is the equivalent spring rate in lb/in of the bags, initial rate to final rate? A wide progressive rate change would make the car wildly unpredictable in a performance application (ie. the track).
Yes, progressive springs can be used in performance applications, but ONLY in very specific applications (for example in one particular track) - I suspect this is what your Japan Team is doing. However, for variety of applications, linear springs are preferred, because they will behave consistently no matter what the conditions.
Similiarly saying that it will work with stock and ALL other dampers seems odd. Dampers are engineered to dampen specific rates. To say that a damper designed to dampen one rate will be applicable to all rates is just wrong.
my thoughts - if you want to slam your car to the weeds, or have ride height adjustability on the fly - this is your product.
no disrespect to you, just the marketing. again, please enlighten me if I'm misunderstanding your product.
pp
Tell you what, lets make this easy... PM me your address and ill send you out a set of bags and brackets to try. Put them on and tell us what you think.
08-14-2006 | 11:29 AM
#49
universal air
Your proposition cleary implies you stand 110% behind your product - bravo. However, I have no interest in installing the product.
I am much more interested, however, in a technical discussion of your products capabilities. You will find that many on this board would appreciate a discussion and understanding of your suspensions dynamics.
As to your other response --> If you can change the static rate by changing air pressure, does that not also change the height of the vehicle? I may be misunderstanding how airbags work, but I thought air pressure was also used to change the height? Example, say I want a 1" in drop and I want 500lb/in front and 450lb/in rear. Can that be done? My impression was that you cannot, but your answer implies that you can. If you can change the pressure in the bag, and by extension the effective spring rate, without changing the bag height, then I am impressed and I will stand wholeheartedly corrected.
Similiarly, can you give us a range of effective spring rates of the airbag in full extension to full compression? this type of information would be essential to properly matching a damper.
thanks and your responses really are appreciated, even though I'm not interested in the product. the more knowledge the better.
pp
Your proposition cleary implies you stand 110% behind your product - bravo. However, I have no interest in installing the product.
I am much more interested, however, in a technical discussion of your products capabilities. You will find that many on this board would appreciate a discussion and understanding of your suspensions dynamics.
As to your other response --> If you can change the static rate by changing air pressure, does that not also change the height of the vehicle? I may be misunderstanding how airbags work, but I thought air pressure was also used to change the height? Example, say I want a 1" in drop and I want 500lb/in front and 450lb/in rear. Can that be done? My impression was that you cannot, but your answer implies that you can. If you can change the pressure in the bag, and by extension the effective spring rate, without changing the bag height, then I am impressed and I will stand wholeheartedly corrected.
Similiarly, can you give us a range of effective spring rates of the airbag in full extension to full compression? this type of information would be essential to properly matching a damper.
thanks and your responses really are appreciated, even though I'm not interested in the product. the more knowledge the better.
pp
Last edited by palepony; 08-14-2006 at 11:34 AM.
08-14-2006 | 01:44 PM
#50
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Joined: Aug 2006
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From: San Bernardino, CA
Originally Posted by palepony
universal air
Your proposition cleary implies you stand 110% behind your product - bravo. However, I have no interest in installing the product.
I am much more interested, however, in a technical discussion of your products capabilities. You will find that many on this board would appreciate a discussion and understanding of your suspensions dynamics.
As to your other response --> If you can change the static rate by changing air pressure, does that not also change the height of the vehicle? I may be misunderstanding how airbags work, but I thought air pressure was also used to change the height? Example, say I want a 1" in drop and I want 500lb/in front and 450lb/in rear. Can that be done? My impression was that you cannot, but your answer implies that you can. If you can change the pressure in the bag, and by extension the effective spring rate, without changing the bag height, then I am impressed and I will stand wholeheartedly corrected.
Similarly, can you give us a range of effective spring rates of the airbag in full extension to full compression? this type of information would be essential to properly matching a damper.
thanks and your responses really are appreciated, even though I'm not interested in the product. the more knowledge the better.
pp
Your proposition cleary implies you stand 110% behind your product - bravo. However, I have no interest in installing the product.
I am much more interested, however, in a technical discussion of your products capabilities. You will find that many on this board would appreciate a discussion and understanding of your suspensions dynamics.
As to your other response --> If you can change the static rate by changing air pressure, does that not also change the height of the vehicle? I may be misunderstanding how airbags work, but I thought air pressure was also used to change the height? Example, say I want a 1" in drop and I want 500lb/in front and 450lb/in rear. Can that be done? My impression was that you cannot, but your answer implies that you can. If you can change the pressure in the bag, and by extension the effective spring rate, without changing the bag height, then I am impressed and I will stand wholeheartedly corrected.
Similarly, can you give us a range of effective spring rates of the airbag in full extension to full compression? this type of information would be essential to properly matching a damper.
thanks and your responses really are appreciated, even though I'm not interested in the product. the more knowledge the better.
pp
However for those who want to tune or the science behind it.
The front bags them self travel from 4" collapsed to 9.5" extended and the capacity is 15 lbs per psi of air pressure. The rear are 20 lbs per psi of air pressure and go from 2" collapsed to 8.5 extended".
Now when you compress the bags down the volume will decrease causing the pressure to increase inside the bag determining your lbs/in of compression.
The more volume you place inbetween the valve and bag the less the spring rate will increase as the bag is compressed.
The less volume between the valve and bags will cause a higher spring rate increase per inch the bag is compressed.
That is why a standard rule of thumb is that the closer your valves to the bags are the stiffer the car is, the further away the softer the car rides.
08-14-2006 | 02:16 PM
#51
Okay, that confirms my understanding of how your airbags work. Then really you could not pick an effective spring rate for a given set height. You can pick how the rate changes (with changing the volume between valve bag) but you cannot specifically choose the rate, correct?
As for what the equivalent spring rates from initial to final, you haven't answered yet. What I mean, of course, is how much force does it take to compress the airbag initially in its stroke and at the end? You mention the "capacity" is 15lb/psi F and 20lb/psi R. I assume by "capacity" is how much weight it can support, which isn't exactly spring rate but it would be a starting point to estimate a correlating spring rate. So, how much PSI is in the bag at complete compression, and how much at complete extension? Your japan team might know the answer to that. If you don't know, by a very rough extension, how much PSI is required to completely raise a 350z, and how much to completely lower?
Tuning this suspension would be incredibly difficult without knowing that information. Unless you have a spring dynometer handy, which again, I suspect your japan racing team does. Obviously the average user would not. Even picking an appropriate damper would be impossible without knowing that information.
quote - "Typically what most people do is they just put air in the bag to get their desired ride height" ---> agreed, i think most people looking at your suspension want to slam to the weeds or have adjustable ride height. this is the suspension for them.
good discussion, thanks
pp
As for what the equivalent spring rates from initial to final, you haven't answered yet. What I mean, of course, is how much force does it take to compress the airbag initially in its stroke and at the end? You mention the "capacity" is 15lb/psi F and 20lb/psi R. I assume by "capacity" is how much weight it can support, which isn't exactly spring rate but it would be a starting point to estimate a correlating spring rate. So, how much PSI is in the bag at complete compression, and how much at complete extension? Your japan team might know the answer to that. If you don't know, by a very rough extension, how much PSI is required to completely raise a 350z, and how much to completely lower?
Tuning this suspension would be incredibly difficult without knowing that information. Unless you have a spring dynometer handy, which again, I suspect your japan racing team does. Obviously the average user would not. Even picking an appropriate damper would be impossible without knowing that information.
quote - "Typically what most people do is they just put air in the bag to get their desired ride height" ---> agreed, i think most people looking at your suspension want to slam to the weeds or have adjustable ride height. this is the suspension for them.
good discussion, thanks
pp
Last edited by palepony; 08-14-2006 at 02:28 PM.
08-14-2006 | 02:43 PM
#52
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From: San Bernardino, CA
Originally Posted by palepony
Okay, that confirms my understanding of how airbags work. Then really you could not pick an effective spring rate for a given set height. You can pick how the rate changes (with changing the volume between valve bag) but you cannot specifically choose the rate, correct?
As for what the equivalent spring rates from initial to final, you haven't answered yet. What I mean, of course, is how much force does it take to compress the airbag initially in its stroke and at the end? You mention the "capacity" is 15lb/psi F and 20lb/psi R. I assume by "capacity" is how much weight it can support, which isn't exactly spring rate but it would be a starting point to estimate a correlating spring rate. So, how much PSI is required to completely raise a 350z, and how much to completely lower?
Tuning this suspension would be incredibly difficult without knowing that information. Unless you have a spring dynometer handy, which again, I suspect your japan racing team does. Obviously the average user would not.
quote - "Typically what most people do is they just put air in the bag to get their desired ride height" ---> agreed, i think most people looking at your suspension want to slam to the weeds or have adjustable ride height. this is the suspension for them.
thanks
pp
As for what the equivalent spring rates from initial to final, you haven't answered yet. What I mean, of course, is how much force does it take to compress the airbag initially in its stroke and at the end? You mention the "capacity" is 15lb/psi F and 20lb/psi R. I assume by "capacity" is how much weight it can support, which isn't exactly spring rate but it would be a starting point to estimate a correlating spring rate. So, how much PSI is required to completely raise a 350z, and how much to completely lower?
Tuning this suspension would be incredibly difficult without knowing that information. Unless you have a spring dynometer handy, which again, I suspect your japan racing team does. Obviously the average user would not.
quote - "Typically what most people do is they just put air in the bag to get their desired ride height" ---> agreed, i think most people looking at your suspension want to slam to the weeds or have adjustable ride height. this is the suspension for them.
thanks
pp
What i am talking about is that you have the ability to adjust the force change per inch depending on how much volume is being compressed.
i.e. full extention to half compression with the valves directly ontop of the bags will give you alot higher rate then with them further away.
08-22-2006 | 05:29 AM
#54
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Joined: Jun 2006
Posts: 5
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From: switzerland
Interesting...really interesting but...
Well I have read this post and sorry I don't have understand all 
...but for making a "short story" 
This system it can be right for a car with about 400hps...or it "just" for "fun"...
I don't make a race but, we all drive a faster car, so it's this system "sure" like a classic suspension kit, or preaps can be a little "delicate" for sporter driver ??
With a non original suspensio we can adjust the height ride, just to lift down...about 40mm (cusco,koni.....ect.ect), with the airbag how is the MINIMUN height for drive in city without problem ??
Really thank Novidem
PS preaps there are a Dealer for Europe where I can ask for e-mail ??
...but for making a "short story" This system it can be right for a car with about 400hps...or it "just" for "fun"...I don't make a race but, we all drive a faster car, so it's this system "sure" like a classic suspension kit, or preaps can be a little "delicate" for sporter driver ??
With a non original suspensio we can adjust the height ride, just to lift down...about 40mm (cusco,koni.....ect.ect), with the airbag how is the MINIMUN height for drive in city without problem ??
Really thank Novidem
PS preaps there are a Dealer for Europe where I can ask for e-mail ??
08-22-2006 | 09:08 AM
#55
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Joined: Aug 2006
Posts: 40
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From: San Bernardino, CA
Originally Posted by Novidem
Well I have read this post and sorry I don't have understand all ...but for making a "short story" This system it can be right for a car with about 400hps...or it "just" for "fun"...
I don't make a race but, we all drive a faster car, so it's this system "sure" like a classic suspension kit, or preaps can be a little "delicate" for sporter driver ??
With a non original suspensio we can adjust the height ride, just to lift down...about 40mm (cusco,koni.....ect.ect), with the airbag how is the MINIMUN height for drive in city without problem ??
Really thank Novidem
PS preaps there are a Dealer for Europe where I can ask for e-mail ??
...but for making a "short story" This system it can be right for a car with about 400hps...or it "just" for "fun"...I don't make a race but, we all drive a faster car, so it's this system "sure" like a classic suspension kit, or preaps can be a little "delicate" for sporter driver ??
With a non original suspensio we can adjust the height ride, just to lift down...about 40mm (cusco,koni.....ect.ect), with the airbag how is the MINIMUN height for drive in city without problem ??
Really thank Novidem
PS preaps there are a Dealer for Europe where I can ask for e-mail ??
08-22-2006 | 09:19 AM
#56
Originally Posted by universalAirSus
For the higher performance applications i always suggest running our bags with a good coilover with adjustable dampening to you can tune it for the ride that your looking for.
Last edited by BhashaZ; 08-22-2006 at 09:21 AM.
08-22-2006 | 09:29 AM
#57
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From: San Bernardino, CA
Originally Posted by BhashaZ
In that case, couldn't you just buy adjustable shocks like Tokico or Koni?
Last edited by universalAirSus; 08-22-2006 at 09:34 AM.
08-22-2006 | 09:51 AM
#59
AirSus,
So what you're saying as far as "tuning" the spring rate with these bags is that: Placement of the valve in relation to the bag will determine how the suspension performs as far as spring rate, etc?
So what you're saying as far as "tuning" the spring rate with these bags is that: Placement of the valve in relation to the bag will determine how the suspension performs as far as spring rate, etc?
08-22-2006 | 09:54 AM
#60
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Joined: Aug 2006
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From: San Bernardino, CA
Originally Posted by NoLimit
AirSus,
So what you're saying as far as "tuning" the spring rate with these bags is that: Placement of the valve in relation to the bag will determine how the suspension performs as far as spring rate, etc?
So what you're saying as far as "tuning" the spring rate with these bags is that: Placement of the valve in relation to the bag will determine how the suspension performs as far as spring rate, etc?