FD Air Cup Suspension
08-09-11, 11:20 PM
#1
Derwin
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FD Air Cup Suspension
Before writing anything I just want to mention that the following is not an offer, is not for sale and is simply an example of DIY I want to share with you.
In some other thread I cannot remember where I know I had mentioned air cup suspension for the FD and some people have talked to me about it so I thought I would share the pictures which are on my local forum.
The background story is that ever since having the Shine Sanai kit put on my car and rocking my Greddy Type S's at 25.5in rideheight I have been have to memorize routes to go where I need and I have found my access to normal roads greatly reduced; a major PITA. Not to mention the uncertainty of going anywhere new....
After talking with a friend of mine about this problem and discussing his car soon to be on the road that would be facing the same problem the idea arose of how to solve this. At that time I was reading Ben Schaffers The Real JDM blog quite often and when I saw the Roberuta suspension on his project R35 everything became so clear, I had to have this on my car.
Two problems; 1- no kit exists for the FD 2- Top Secret wants 5,000$ for 4 corners.
At this moment my friend looked at me and said "but why don't we make our own?" Fast forward one year later and these are the results, bolt on for the FD with improved piston design, greater stroke. Hope you like it cheers!
In some other thread I cannot remember where I know I had mentioned air cup suspension for the FD and some people have talked to me about it so I thought I would share the pictures which are on my local forum.
The background story is that ever since having the Shine Sanai kit put on my car and rocking my Greddy Type S's at 25.5in rideheight I have been have to memorize routes to go where I need and I have found my access to normal roads greatly reduced; a major PITA. Not to mention the uncertainty of going anywhere new....
After talking with a friend of mine about this problem and discussing his car soon to be on the road that would be facing the same problem the idea arose of how to solve this. At that time I was reading Ben Schaffers The Real JDM blog quite often and when I saw the Roberuta suspension on his project R35 everything became so clear, I had to have this on my car.
Two problems; 1- no kit exists for the FD 2- Top Secret wants 5,000$ for 4 corners.
At this moment my friend looked at me and said "but why don't we make our own?" Fast forward one year later and these are the results, bolt on for the FD with improved piston design, greater stroke. Hope you like it cheers!
08-10-11, 09:22 AM
#5
Derwin
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Air cups go over your coilovers to raise and lower the suspension momentarily to avoid obstacles.
Things I could not have imagined also were that the type of anodizing used greatly affects the lifespan of the material. So what has been done is not for aesthetics purposes but for durability purposes.
Re – whether it works or not, everything was calculated beforehand for the Piston area, pressure, vehicle weight.
Things I could not have imagined also were that the type of anodizing used greatly affects the lifespan of the material. So what has been done is not for aesthetics purposes but for durability purposes.
Re – whether it works or not, everything was calculated beforehand for the Piston area, pressure, vehicle weight.
08-12-11, 11:40 PM
#7
Derwin
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As mentionned earlier, this is not a for sale thread.
If it were to become for sale naturally we would be looking to undercut what exists on the market pricing wise.
Videos will be uploaded as soon as everything gets in motion. Thank you for the words of encouragement!
If it were to become for sale naturally we would be looking to undercut what exists on the market pricing wise.
Videos will be uploaded as soon as everything gets in motion. Thank you for the words of encouragement!
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08-15-11, 11:44 AM
#9
Nice work!
I have wondered when these were going to be made by aftermarket for sports cars, I didn't know they already were.
One issue you may run into is that in the normal (down) position you are running with the piston further down the shock body then the manufacturer had planned and it is possible to cause damage from bottoming.
I know when I was having my FC coilovers worked on at JIC I was hot to get tender springs on the rear for some droop (seems to be the accepted hot set up for FC now). They wouldn't do it.
It would be best if the coilovers you had started with had tender springs to begin with which you would remove and have your lifts actuate that same distance they used to collapse normally.
Your project is looking awesome!
I have wondered when these were going to be made by aftermarket for sports cars, I didn't know they already were.
One issue you may run into is that in the normal (down) position you are running with the piston further down the shock body then the manufacturer had planned and it is possible to cause damage from bottoming.
I know when I was having my FC coilovers worked on at JIC I was hot to get tender springs on the rear for some droop (seems to be the accepted hot set up for FC now). They wouldn't do it.
It would be best if the coilovers you had started with had tender springs to begin with which you would remove and have your lifts actuate that same distance they used to collapse normally.
Your project is looking awesome!
im not familiar with either
08-17-11, 01:47 AM
#17
Alex, where do I send my CC info? 
W/O knowing a whole lot about this, I'm guessing the 'bags' tuck over the coils? I have FEED coilovers, which looks a little different. Do you think it'll work?
http://www.fujitaengineeringusa.com/...s/tune/28a.jpg
W/O knowing a whole lot about this, I'm guessing the 'bags' tuck over the coils? I have FEED coilovers, which looks a little different. Do you think it'll work?
http://www.fujitaengineeringusa.com/...s/tune/28a.jpg
08-17-11, 08:26 AM
#18
Radioactive Rotary Rocket
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Interesting. This must be what they're putting on the height adjustable super cars when they need to go over a bump. Like the Zonda and Veyron.
Does the aircup add any spring rate when it's down? Like is there still a little bit of rubber or how does that work? Like when there isn't any air inside of it, is it metal on metal or what? I wish I could see a cut-thru of how the air cups actually work.
Does the aircup add any spring rate when it's down? Like is there still a little bit of rubber or how does that work? Like when there isn't any air inside of it, is it metal on metal or what? I wish I could see a cut-thru of how the air cups actually work.
08-17-11, 09:23 AM
#19
Pretty interesting concept, yet seems rather simple to me. Much props to you!! Also seems that your machining looks top notch! Did you manufacture this in house or job the machining out?
Seems to me that this should not affect handling (change spring rate) when fully decompressed, as the adjusting part should be bottomed out. Is this correct?
How much hight does this add to the coil?
What kind of air pump are you planning on using?
Feel free to PM me, as I would like to talk too you about this product.
Thanks,
Brandon
Seems to me that this should not affect handling (change spring rate) when fully decompressed, as the adjusting part should be bottomed out. Is this correct?
How much hight does this add to the coil?
What kind of air pump are you planning on using?
Feel free to PM me, as I would like to talk too you about this product.
Thanks,
Brandon
08-17-11, 03:26 PM
#22
Derwin
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Alex, where do I send my CC info?
W/O knowing a whole lot about this, I'm guessing the 'bags' tuck over the coils? I have FEED coilovers, which looks a little different. Do you think it'll work?
http://www.fujitaengineeringusa.com/...s/tune/28a.jpg
W/O knowing a whole lot about this, I'm guessing the 'bags' tuck over the coils? I have FEED coilovers, which looks a little different. Do you think it'll work?
http://www.fujitaengineeringusa.com/...s/tune/28a.jpg
The only way I would know if the FEED would fit is to have them infront of me unfortunately. Other than the OD and ID of the spring there are other measurements to take.
I don’t understand your question.
Pretty interesting concept, yet seems rather simple to me. Much props to you!! Also seems that your machining looks top notch! Did you manufacture this in house or job the machining out?
Seems to me that this should not affect handling (change spring rate) when fully decompressed, as the adjusting part should be bottomed out. Is this correct?
How much hight does this add to the coil?
What kind of air pump are you planning on using?
Feel free to PM me, as I would like to talk too you about this product.
Thanks,
Brandon
Seems to me that this should not affect handling (change spring rate) when fully decompressed, as the adjusting part should be bottomed out. Is this correct?
How much hight does this add to the coil?
What kind of air pump are you planning on using?
Feel free to PM me, as I would like to talk too you about this product.
Thanks,
Brandon
The height that is added is the amount of material used on the piston cup.
The airpump will run 200 psi and fill the system from zero in 2 minutes. I think Roberuta uses a Thomas compressor that runs 150psi.
Interesting. This must be what they're putting on the height adjustable super cars when they need to go over a bump. Like the Zonda and Veyron.
Does the aircup add any spring rate when it's down? Like is there still a little bit of rubber or how does that work? Like when there isn't any air inside of it, is it metal on metal or what? I wish I could see a cut-thru of how the air cups actually work.
Does the aircup add any spring rate when it's down? Like is there still a little bit of rubber or how does that work? Like when there isn't any air inside of it, is it metal on metal or what? I wish I could see a cut-thru of how the air cups actually work.
08-17-11, 11:24 PM
#25
Radioactive Rotary Rocket
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It's just kind of new for me. I know people have been doing this stuff for a long time, but it's like just a few years ago when nobody understood turbos clearly.
Please prevent an air cup version of this from forming in my mind.
Please prevent an air cup version of this from forming in my mind.