EOI: D22/D21 IFS Air Ride AND Long Travel Kit

THIS THREAD HAS BEEN UPDATED - SEE POST #10 BELOW FOR CHANGES

This is a thread to gauge interest in a possible future kit which would convert the front IFS suspension of a D21/D22 from being suspended by torsion bars and damped by shock absorbers, to being suspended and damped by a strut-type airbag-over-damper assembly.

Such a kit would comprise of bracketry and reinforcement necessary to change the spring type, two air struts, and the necessary plumbing. Regarding legality, the kit would be complianced for Australian states prior to sale. The idea is that the evidence compiled in conjunction with my VASS engineer is provided to your engineer that the modification is safe, so that your engineer can produce a certificate without expensive testing.

Don't be too concerned with discussing whether it will fit/work/break, this thread is simply to determine if such a product is of interest to the market.

This kit would...
- ...increase on road ride comfort. Air springs are fitted to some upmarket luxury vehicles, ie. Range Rovers.
- ...make possible the adjustment on-the-fly of ride height, making it easy to enter low clearance areas, increase clearance to negotiate obstacles, increase clearance during oil services, or lower vehicle to improve access to the engine bay.
- ...make possible, through the use of a solenoid block, the cross-linking of air springs, creating an effective zero spring rate. In uneven terrain, as one wheel is forced up, the other wheel is forced down, similar to solid axle vehicles. Whilst this does not increase the range of travel, which is still limited by the bumpstops, it does increase the compliance of the suspension, allowing it to follow the terrain better. This feature would be activated from the cabin via a switch when travelling off-road.
- ...negate the need for a sway bar disconnect, as the zero spring rate contribution from the air springs when the link is activated, allows the control arms to articulate more despite the presence of the sway bar.
- ...increase access (by complete removal of the torsion bars) to the transmission, allowing the transmission to be removed without removing torsion bars, significantly reducing labour costs for clutch replacement etc.
- ...be compatible with aftermarket UCAs.
- ...make easy the adjustment of suspension after fitting a winch/bullbar/dual battery.

The spring rate ("hardness") of air springs is defined by their volume, whilst the height of the spring, which affects ride height, is determined by pressure, so ride height can be maintained (or altered) with differing loads, without affecting spring rate noticeably.

With so many variables, it is difficult to produce an accurate estimate for the total price of such a kit, however expect the basic kit (no air compressor or extras) to cost roughly somewhere in the range of $2k-$2.5k. If nation-wide compliancing is deemed impossible, this price will drop considerably.

Fitting would require grinding/welding to the chassis and LCA, painting, and basic spanner work. The above rough estimate does not include fitting.

Expressions of interest please.

Sounds interesting Dion.

A suggestion, it may be worthwhile including new UCA's and incorporate them into a package price. Getting a decent lift out of the whole deal may offset the cost and make it more attractive to some people?

Just a thought, will be watching how this progresses if it does. Good luck.

Jason said:

Sounds interesting Dion.

A suggestion, it may be worthwhile including new UCA's and incorporate them into a package price. Getting a decent lift out of the whole deal may offset the cost and make it more attractive to some people?

Just a thought, will be watching how this progresses if it does. Good luck.

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+ 1
Sounds interesting..

Dion that's awesome, I for one will be all over this like white on rice if it's engineerable.

It just has so many plus's!!

Would the kit be readily available once all the ground work is done or will it be an order only type deal?

As Jason said incorparating the UCA in the price would be benificial

The option to go up and down in hieght on the fly is a dream come true. I run two sets of tyres and have to have the torsion bars wound way up to get my muddy's underneath. The missus hates having it like this as the ride is kinda harsh, not to metion the option to lower to work in the engine bay i'm drooling at the moment haha

Keen to see what you do with this.

BOOGZ STR said:

Dion that's awesome, I for one will be all over this like white on rice if it's engineerable.

It just has so many plus's!!

Would the kit be readily available once all the ground work is done or will it be an order only type deal?

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Since there's so many options (regular or single/double adjustable shocks, air compressor included or not included) I'd probably do them to order. I'd keep bracketry in stock.

BOOGZ STR said:

As Jason said incorparating the UCA in the price would be benificial

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Yeah so far everyone seems interested in the UCA being included, so I'll include it. If doing my own UCAs instead of buying them it, it starts to become even more worthwhile to produce a long travel kit.

BOOGZ STR said:

The option to go up and down in hieght on the fly is a dream come true. I run two sets of tyres and have to have the torsion bars wound way up to get my muddy's underneath. The missus hates having it like this as the ride is kinda harsh, not to metion the option to lower to work in the engine bay i'm drooling at the moment haha

Click to expand...

That is exactly the situation I'm in.

depending on cost and ride quality offroad ill be in

I'll definitely be watching this space as well.

Definite maybe

Since it seems there is a fair bit of interest in aftermarket UCAs being included in a package, I've decided to also look into producing a long travel suspension kit. These use longer control arms top and bottom with longer half shafts to increase wheel travel.

Compared with the initial kit described above, this would provide numerous extra advantages by...
- ... allowing D2# Navaras finally to be lifted more than 3" in the front end,
- ... providing increased flex off road whilst maintaining on-road ride quality, and,
- ... avoiding the need to cut or weld to the chassis, producing an entirely bolt-on kit.

This kit would contain the following components:
- Upper Control Arm with bushes x2
- Lower Control Arm with bushes x2
- Steering tie-rod extension x2
- Extended CV shaft x2 (using a common CV for cheap replacement)
- Extended stainless braided brake line x2
- Air spring x2
- Air hoses as req'd
- Air solenoid block and electronic controller.

Plus the following optional components:
- Fiberglass flare spacers (in-house)
- Larger bore shock absorbers (as the damping ratio is affected)

So, more than 3" lift and better flex - anybody else interested now?

Dion i can't believe the isnt more interest before your last post, i'm mega pumped for this and everyone who i have spoken to with IFS 4bys reckon its awesome.

Put me down for a kit once you get it rockin!!

I will be watching this with interest. Especially if it can be engineered in QLD.

i would be interested in a 3"+ flex kit for sure

Sounds good, I will be watching this space

Live in Qld and not really sure about what you are trying to acheive.(Ignorance) Will this involve engineering cetificates and would it be better than getting 2 inch suspension lift and what would it cost?

Blu Roo said:

Live in Qld and not really sure about what you are trying to acheive.(Ignorance) Will this involve engineering cetificates and would it be better than getting 2 inch suspension lift and what would it cost?

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G'day Blu Roo,

What is this trying to acheive - The common complaint regarding IFS vehicles is that they don't have enough articulation - this is just how it is. There's not much aftermarket available for Navaras to improve on this for people who use them offroad.

This proposed kit would combine longer top and bottom suspension arms and linked airbag springs (one goes up - pushes the other down) to improve the articulation as best we can, without going to a solid axle swap. Solid axle swaps, if done well and especially if done by a pro, can cost a lot of $$$. Many people want to keep the IFS because it handles better and rides better. Best-of-both-worlds kind of thing. This is only market research at this stage.

Engineering certificate - yes, if you want to remain 100% legal (that's up to you), but the same applies to a combined 2" suspension and 2" body lift, or a 2" suspension and 2" larger tyre combination, etc etc. You can't do much without needing engineering. Regarding QLD specifically - I haven't determined yet whether this would require just a mod plate, or a blue plate (more complicated). With any luck, I can get the kit pre-approved and then your engineer would just have to sign some paperwork, rather than having to perform a lane-change test.

Better than a 2" lift - In a nutshell, yes. A 2" lift just changes the ride height, it doesn't increase the available articulation. Also, the biggest lift available now is 3" and costs around $750 just for the upper arms (no springs etc) - I'm proposing a kit that can provide a 5" lift with more articulation and adjustable front ride height.

Cost - the total cost would include the kit, fitting, a wheel alignment, and a certificate. I can only control the kit price. Rough estimate has the kit at $2000-$2500. You get a lot for your money there, compared to Caloffroad kits etc.

Done.

Sorry haven't been on for a day.

Dave said:

Done.

Sorry haven't been on for a day.

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Thanks mate, no worries.

definately in

I'd definitely go for one if it does what it sounds like it will