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Would you want an air-ride system on your van????

Ripples in the water............air ride for the T4

171K views 637 replies 93 participants last post by  Or_GazM 
#1 ·
Ok guys and girls.
Just a mini update for you all but, Keith (T4chippy) and I have been chatting rubbish in the shadows and have potentially come into contact with someone about an air-ride system for the T4.:eek: It's early days and nothing can be promised. I will keep you all abreast of the latest info and detail when and where it happens.I:

If it works there could be a decent discount for forum members as well... again, not final as this is mega early days. H:
 
#111 · (Edited)
Just posting this for my reference T:
http://forums.vwvortex.com/showthread.php?3950653-Airbags-with-Torsion-Bar&p=50221959&viewfull=1


Just wondering what people's thoughts on the following are......what is the objective here???

Are we trying to..

A : improve the ride on the front while being low and having the ability to raise and lower at our convenience

OR

B : just have the ability to Raise back up to stock from being low??

If the answer is B then I'm sure there's a way of devising an electromechanical solution that adjusts the torsion on the TB replacing the adjustment bolt and nut or as Alex says, replace with an air bag ?? and then bags on the rear??


The above is just ramblings but feel free to comment/discuss/find flaws T:
 
#119 ·
Hi everyone,

I'm Jonathan from air-lift.co.uk, i.e. "that bloke" Keith and Gareth have been talking to. I just thought I should pop my head in with the hopes of answering some questions and maybe learning a thing or two myself.

Firstly I want to thank Wink749 for posting all the pics and details. We haven't fully concluded how the T4 system will work, it will most likely be a little different to this install though we're very much in the ideas stage still so any input is really useful T:

I think a few of you have our Load Support kits fitted (recognise a few names!). They're useful for, well, load support, the idea being to stiffen things up and stop the van from swaying/rolling/sagging/bottoming out when under load. The only thing is they don't offer much in the way of height adjustment and there's nothing that we have to offer for the front, so we're looking at something fairly different.

The rear system will most likely replace the coils with air springs, as has been pointed out here. The front will be a bit more involved of course given the limited space and torsion bar setup, but we have a few ideas. One of the main aims is to keep the van as unmolested as possible and keep the installation reversible, so we want to avoid any major modification aside from the odd drilled hole (hopefully not even that!). Of course there would probably be a bit more to it if you're really looking to scrape the chewing gum off the road, but we'll try and look at both options.

Anyway I'm sure there are a few questions, fire away!

P.S. I really hope I'm not treading on any toes or coming across as simply "advertising my wares". I don't own a T4 personally but am very much a VW man, mainly air-cooled but there we go!
 
#120 ·
Welcome aboard Jonathan, hopefully with your input we should be able to get the the bottom of this conundrum and achieve a commercially available kit or kits (depending on budget)

As long as it's just advice and development you are doing at the moment and not "flogging your wares" I can't see a problem. As soon as we achieve a system for the T4 and T5 though that might change T:

Have you any questions for us?? Need any more pics etc

Can you answer any of the concerns above I.e paul20v's concerns about the lower ball joint ??

Welcome aboard T:
 
#123 ·
Evening all,

Hi Dan - no problem, glad you made it back!

Gareth - cheers for that, hopefully with your input combined with the info on here we'll come up with something that does the trick.

Can you answer any of the concerns above I.e paul20v's concerns about the lower ball joint ??
Keith, and Paul - I wouldn't like to make an "official statement" on this but I can see both sides really, although admittedly I'm only working from diagrams and pictures at the moment so please forgive me if I've got anything hideously wrong here:

I kind of agree with Paul here, you certainly wouldn't want to put any undue force onto a balljoint that wasn't designed for it. As I see it the additional stress on the balljoint would be caused by the heavily lowered (read raised upward toward the cabin) torsion bar pulling in the opposite direction to the force of the bag. Then the air bag pushes the lower arm downwards so that when the van is raised, and this is a very extreme way of putting it, it's as if the torsion arm and the lower arm are having a tug of war, with the hub carrier assembly as the rope.

Now that lower arm, hub and both balljoints will withstand substantial upward forces - hit a bump at speed, the lower arm retracts up toward the cabin and the first thing to take the energy is the shock absorber on that arm, balljoints are pushed together, no problem. However the only downward forces it was "designed for" is that of the hub assembly - go over a hole with one wheel, and it's just the force of the wheel, hub, brake, etc will be on the balljoints, minus the reaction of the torsion bar and rebound damping effect of the shock absorber.

The reality of this however, is that the guys in Wolfsburg would have designed the assembly to take a lot more than that. Those balljoints should (and I'm only estimating here) withstand a force of say, 15-20kN? Assuming the torsion bar is adjusted correctly, and since the bags on Wink749's setup aren't very tall, they probably won't displace the torsion bar enough to reach that kind of opposing spring rate. This means that while the setup isn't ideal, it's probably not a cause for concern.

Sorry if that's a bit long-winded, Gareth can confirm that I tend to "go on a bit"! It's all a bit academic because I hadn't even considered using the lower arm until seeing the pics, I'm hoping to use the upper arm, therefore only bending things that were designed to be bent in the first place.
 
#122 ·
Welcome on the T4 train mate.

I'm back in the house and back to reality mate so, I'll look at getting all those bits for you that you had questions for by monday.T:
Here's to new and big things to come. A:
 
#125 · (Edited)
cant believe it . claire has given me the go ahead for this if/when you get it right . what we looking at price wise ? a couple of k ? how much are the systems you already have on the market , need to know to count the pennies T:
also could the compressor and gubbins be mounted underneath the van , limited room inside to be honest !
 
#126 ·
I hate to go on about it but the weight of the van will be pressing the ball joint apart in a downwards direction so it will be working the complete opposite of whats its designed to do
I cant be the only person to see this as a problem as there was a thread o coil overs on here to and the coil over was mounted to the lower shock position and i was not the only one on that thread too point out that the force was pushing the ball joint apart with the weight of the van
Its only designed to hold the hub in place and has the damper forces applied to it not the weight of the van which is what the coil overs were doing and the air bag by being mounted to the lower arm
Paul T:
 
#129 ·
I must say i agree with Paul, having a bottom ball joint go with no warning is no joke and that was on a stock set up introduce coil over or a system similar to the one being discussed is in my mind a folly, alot of work and thought on this is needed, and nobody should be under the illusion that it will happen tomorrow, speaking s an engineer of over 30 years, messing with a stock system is good enough but redesigning a system and incorperating something that shouldn't be there in the first place and expecting it to work as good as a factory system is in my opinion optomistic to say the least, especially as the kit will be supplied as DIY. I don't want to pi ss on any ones chips, but caution is key. Best of luck.
 
#142 ·
Hi folks, another long one from me!

Thanks aggie for the info. I wouldn't want to weld anything to the actual torsion bar directly for various reasons, unless I've misunderstood and you're talking about welding to a rigid part of it? Either way the top arm and torsion bar is definitely the area we're looking at, and that's a very interesting theory for tackling it from the other side. Much better to only put the big forces on the bits that were designed to do so in the first place.

You're right in pointing out the other mods/limitations for "slamming", as I said I'm only working from pics and diagrams at the moment so it's useful to know what's going to be the first limiting factor. We're hoping to get a kit together that will allow for enough travel should the installer wish to make extra mods and get it lower, but at the same time allow for a reasonable amount of adjustment without the mods. Anything else beyond that will be up to the person fitting the kit, such as tucking the wheels under the arches and protecting the underside, but it's all relevant.



It sounds as if you and I have a similar view on modifications. Manufacturers put good engineers and millions of pounds/euros into the design of these systems to find a balance between each of the variables (eg clearance, comfort, handling, reliability, safety, cost etc), so when it comes to modifications more often than not something, or some things, ends up being compromised for the sake of another, and without being inside the head of the original engineers it's tricky to know which areas have sufficient room for modification. You're very right to say caution is key.

What I'm getting at is that we're not looking to just knock a couple of brackets together, say "that'll do" and offer them up for sale - that'd be easy, but also kind of foolish, if that were the case the first build would be on the way. We're looking at some pretty extensive R&D before the first working prototype is made, then multiple prototypes before anything is installed and tested. Only once (or if) a satisfactory design is found will we fire up the CNC and hopefully bring out a product.

Admittedly it'll be impossible to get a single system to appeal to everyone's taste, some will want to drop it fully, others will just want adjustment, an improvement of ride quality or even to raise it upwards more, but here's where this discussion comes in handy to gauge what people are looking for, and what has already been considered.

cant believe it . claire has given me the go ahead for this if/when you get it right . what we looking at price wise ? a couple of k ? how much are the systems you already have on the market , need to know to count the pennies T:
also could the compressor and gubbins be mounted underneath the van , limited room inside to be honest !
Great stuff. The mounting locations will be left up to the installer, though we'll certainly have some suggestions eventually. The compressor it's self isn't that big, off the top of my head they're approximately 300mm long, 200mm high and 100mm wide, but will need to be protected from the elements to some extent. The main bulk of the system is the reservoir, though there are a few different shapes and sizes available. You might in fact get away without a reservoir but it'd be very slow, and you'd lose the benefit of being able to inflate tyres and such - surprising how often having a compressed air supply on board can come in handy!

The big question on everyone's lips, price: it's very difficult to say at the moment, however to give you a bit of an idea most fully adjustable systems start from about £1600, and can go upwards from there for digital controllers and other "bells and whistles". This is for an off-the-shelf kit though, so the cost will depend largely on what kind of mountings we're looking at. Though of course there will be some kind of group discount/bulk buy arrangement should the idea get off the ground.

Keith that van is mad! Very cool but I don't think I'll be doing that sort of chopping :eek: Bargain though when it sold, looking at the amount of work that went into it!
 
#130 · (Edited)
I have been closely watching this thread unfold from the start and have also been thinkin about air ride for the front end for some years now.
Myself and t4ste have examined the complete front suspesion setup many times for both coilover and air ride suspension.
Our conclusion was that the lower arm is not capable of solely carrying the nose weight for a coilover or airshock when bolted through the shock/ARB mounting hole,there simply isnt enough material here to be reliably strong enough.Compare the design and structure of the top arm(that currently carries the weight) and bottom arm and you will soon realise this.

I have measured the nose,tail and overall weights of the various T4s available and would not trust the bottom arm to carry the nose weight,the bottom ball joint is also being forced out of its socket as mentioned previously in this thread.

I have seen bottom ball joint falure on T4s with standard and lowered suspension and the result is that the drive flange is pulled from the transmission and the CV joints destroyed,the gearoil is thrown all down the road and the T4 is very difficult to recover from the roadside and usually requires repairing where it stopped.New parts are driveshaft,driveflange seal,gearoil and bottom ball joint.Sometimes the tyre and wheel can be damaged and the wheelarch requires repair/replace and paint.

The front bag setup in this thread has the bag mount/platform added to the bottom arm which in theory should strenghten the arm (only the area it covers though) but not the ball joint.

I have tested the full travel of the front suspension with the ARB,shocker and top mount removed and found that before the top arm touches the chassis rail the flange for the torsion bar attachment at the rear of the top arm fouls the subframe as it turns so this area will have to be clearanced/notched as will the chassis rail to allow for the T4 to lay out.When layed out both ball joints will be at thier full extent of travel.
The upper shocker mount will have to be reworked around the notching and much shorter ARB drop links used and the subframe clearanced to avoid the ARB fouling.
The steering track rods will also foul the chassis rails and thier working angle will be extreme unless a bump steer kit is fitted like the old days of air cooled before drop links were introduced.

The front inner wheel arch tubbs on the T4 are really shallow and tyre contact is imminent so even with all the above mods getting it down in the weeds will require inner arch treatment.
The next problem is sump and gearbox contact with the floor,this cant be raised much because the driveshafts will foul the underside of the upper arms.
The fuel tank also hangs lower than the sill lips and cant be raised so unless a new tank is fabricated it will never layout on the deck

Now here is my solution :- once all the above mods have been completed (except the last three unless wanting extreme) is to mount the bags inboard on the rear of the subframe in the void between the two rear bottom arm mounting bolts,the platform should be welded into place to be strong enough to mount the bag platform on to support the weight of the T4.The bags will be connected to the torsion bars via a strong enough lever bar that will be proffesionally welded onto the torsion bar where it exits the upper subframe.At the rear of the torsion bar the lever and adjusting bolt mechanism will be removed and a bracket fabricated to hold the bar up in the saddle securely but so it can still pivot.This way the bottom arm and ball joint will be under no more stress than intended originally by VW
What i dont yet know is if the spring steel that the torsion bar is made from can take such a weld that will be sufficiently strong enough to do the job.

So as you can see i have been giving this some thought and investigation for quite some time now,whats stopping me from progressing is the financial aspect,having the spare time (i work on T4s all day every day) and having a spare T4 to experiment on as mine is my daily transport.
I also think that to be able to buy a bolt on DIY kit for the T4 is not a viable option at this moment

Hats off to wink for his evolution of the kit supplied and installed by a certain hydraulics company and bringing it to the
T4forumT:
 
#131 · (Edited)
Thanks alot for your input Steve, much appreciated T:

I'm sure it will give Jonathan a few things to think about :D

So maybe for those of us that don't mind not being uberlow the bag instead of the adjustment rod and nut maybe a cheaper alternative?

Can anyone confirm that these two T4's are "edition eight" projects?? Was thinking about contacting them for some more input. (think it's actually written on the black one I:) or is this hydraulics d'ya reckon :*





EDIT : nevermind found it I:
http://vwhome.blogspot.com/2010/07/edition-eight-low-buzz.html
http://galerie.motorfacts.de/main.php?g2_itemId=176922&g2_imageViewsIndex=1
 
#135 ·
These two are one T4 in two colours.
Its using the full front end (except bodywork) from a golf either mk3 or mk4 chassis rails,subframe,struts,hubs etc,no pics of the interior cab area have ever been posted on the web so what the dash is like with the strut intrusion is a mystery.
The rear end is bespoke and intrudes into the rear load area,similar to that you find find on the back of a modern PSV that drops to kerb level for passengers to get on/off easier.

So its very heavily modified indeed to achieve the greatly desired "LAYEDOUT" look
 
#144 ·
Well that's me back for my weekend racing. Awesome input going on here guys and girls. This is probably helping out no end in coming to a conclusion to how we'll be tackling this.

Jonathan, I'm off out for a bite of lunch and once I'm back I'll be getting said measurements for you. I'll probably give you a bell as well if your not too busy.
 
#146 ·
Just a quick update for you all. Jonathan and I have had a natter today about what's going to happen. Steve (my van) will be off to see him in the second week of November to start the actual hands on physical work. He's got free rain to do whatever he needs to do to develop it for a good 6 months so, there could be a few options R&D'd properly for the rest of the commercial market/buyers.T:
 
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