EvaResto Premium -'59 Rear Air Kit install Guide
Thank you for purchasing an EvaResto Air Suspension kit. This guide should tell you everything you need to know about fitting and operating your kit, but if you have any questions or are unsure of anything, feel free to email or call us and we’ll assist as soon as possible!
Please note:
Any work on the suspension system of your car is safety critical, and EvaResto LTD Strongly recommend this suspension system be installed by a Professional Automotive technician, ideally with prior experience fitting air suspension systems.
If you're unsure or inexperienced in this field, please seek the help of a professional installer!
EvaResto LTD takes no responsibility for faults that occur in the instance parts have been installed incorrectly or instructions not followed correctly!
This kit is designed as an easy to fit, well performing and highly practical air ride system for Type 1 Pre '60/'59 model year cars. It is an ’independent’ kit and will replace the original style torsion bar setup in full.
Care must be taken out at every point to ensure the kit is installed correctly. Once it is in place, no ‘servicing’ of parts is required, but it is recommended that you check on the system periodically to make sure everything remains in top order.
Please note: This kit is designed for use with independent management types (4-way), and will perform it’s best if used as so. 2-way systems will operate it, however wont allow for the best performance
+ ride levelling available.
Fastener kit:
All Necessary fixings are packed together.
Metric tools are required for install.
- 2x ‘U’ Bolts with Nyloc m8 nuts & Washers
- 8x 3/8” UNF Bolts (For Airlift Bags)
- 2x M10x60 Bolts
- 12x M12x35 Bolts
- 2x M12x40 Bolts
- 4x M12x50 Bolts
- 6x M12x60 Bolts
- 10x M10 Washers
- 44x M12 Washers
- 24x M12 Nyloc Nuts
Preparation
Get yourself and the car ready for the job.
Ensure vehice is safely lifted and supported, using safe and correctly graded equipment. Wheels removed, necessary tools to hand
Note: Your kit may differ slightly in visual
design to the kit depicted in this fitting guide.
Car Preparation
Your original suspension system must be almost entirely removed for the new kit to be installed. Don’t worry though, there’s no cutting or fab work needed,
and the full kit is only bolt-on. Parts that will need removing entirely are:
- Shock Absorbers
- Spring Plates
- Torsion Bars
- Rubber Bump stops and mounts
- Original brake hard lines from axle to hub
- Heat exhangers & tubes - Replace with J
Tubes.
With all of your existing setup removed, you should be left with something like this:
Now for the install guide...
Step 1
Installing the Top Mount Halves.
Before fitting the Top Mount Halves into the vehicle, it is necessary to fit the Airlift Air Bags into place first.
Start by fitting the Air Fittings into both bags, using suitable thread sealant (loctite 565 recommended for best results). Install the fitting into the threaded ports on the bags. They don’t need to be fully tightened down, as they are an NPT (tapered) thread type.
Images show what a normal fit looks like. Do not overtighten these!
The bags can then be fitted into the top mount halves.
Do this with the supplied 3/8" UNF Bolts, and m10 washers. There are two threaded holes on both the top and base of each Air Bag. Two slotted corresponding holes are cut into the top mount halves.
Where in the slotted adjustment you fit the Air Bag is down to clearance between the air bag and shock towe/axle. Fit this mid-way for now and tighten down.
With the bags affixed to the top mount halves, fit each one into the chassis. Using M12x60 Bolts through the factory shock mount, and securing with a washers, and nyloc nut on the outside.
(Note, bag not fitted in pic!)
Do not fully tighten these fixings yet.
Lift the 'leg' of the Top Mount halves up into the torsion bar tube, and secure loosely with the m8 U-Bolts supplied
Step 2
Fitting the Cross-Brace bar.
The Cross brace bar connects both of the Top Mount Halves together, and fixes in place with 4x M12x35 Bolts, washers and Nuts.
Bolt this part to the Front of the Top Mount halves, do not fully tighten the fixings yet.
Shown below outside of the vehicle:
Step 3
Tighten down all fixings.
Start with the M12x60 Bolts through the Top Mount halves, then the Cross-Brace bar fixings, and finally the M8 U-Bolt fixings around the torsion tube.
Ensure the Leg of the top mounts are straight and match positions on left/right side of vehicle before tightening down the U-Bolt Fixings.
The Top mount is now Mostly in place, and the most awkward part of the install over!
Step 4
Fitting the Frame Horn Clamps.
The Frame horn clamps are made up of 2x pieces each, and secured to the chassis with M12x35 fixings, washers and nuts.
Offer them in place like pictured, using the Lightning Bolt cut-out to help centralise them.
Mount them as close to the gearbox cradle as possible, then fully tighten down.
There is one clamp per chassis ‘horn’.
Step 5
Fitting the Stiffener bar assemblies.
The stiffener bars help pre-load the top mount assembly, making it as rigid as possible and helping to spread the suspension weight safely through the shock mounts, frame horns and torsion tube.
Bolt each stiffener bar in place using 4x M12x 35 fixings, 4x Washers (only needed on one side) and 4x nuts. Adjust the bars by twisting, to allow for no pre load either way (can be twisted by hand easily), then fully tighten down the M12 fixings.
In order to pre-load the top mount assembly, the stiffener bars must be tightened (made shorter) by 1 full turn past hand-tight. Use the spanner flats machined into the rod, and once achieved, lock the assembly in place with the Jam nuts.
The top Mount is now fully installed!
Step 6
Step 7
Fitting the Freeroll Air Ride spring plates.
The Spring Plates supplied with the kit are designed to work with OE size bushings (1 7/8" inner and 1 3/4" outer). Your original rubber bushings can be used here if they are in good condition.
Our Preference here is Urethane bushings. These used with Red Rubber Grease will give great noise-free, smooth results.
If using OE rubber, use the same type grease for best results.
Fit the Freeroll plate into the chassis like usual and secure in place with the spring plate cover. Ensure the outer bushings you have match the plate covers you have (knobbly/smooth type).
Step 8
Fixing the axles to the Freeroll plates & Lower bag mounts.
The lower bag mounts secure in place through 4 points. 3 being the spring plate-to-axle fixings, and the 4th being the original lower shock mount on the axle. Used are 1x M12x40 bolt, 2x M12x50 Bolts and 1x M12x60 bolts per side.
Lift the axle into the spring plate + Lower Bag Mount and pass the M12x40 Bolt + washer through the front most hole of the Lower Bag Mount, passing through the Spring plate and Axle.
The rearmost holes take M12x50 Fixings, and the lower factory shock mount a m12x60. Install all with washers, with threads facing outwards to avoid any issues with bag clearance.
The rearmost m12x50 Bolts also secure the Lower Shock Relocator brackets, so slip those on before adding washers and nuts.
Don't tighten these down fully, as the tracking/wheel alignment needs to be set at a basic level before this assembly is tightened down.
Like factory, the toe is set by moving the axle forwards/backwards in the adjustment slots in the spring plate
MAXIMUM toe IN shown above,
MAXIMUM toe OUT shown below
Note the V-groove cut into the spring plate. The FreeRoll spring plates are extended over stock units to allow for a corrected wheel toe angle when running low ride height, so with this in mind, set the rear toe adjustment about mid way in the adjustment slots on the spring plate. This will work for 90% of setups.
Once this is matched side to side, tighten down all fixings on the lower mount fully, and tighten the 3/8" UNF bolts into the bag.
The lower mounts are now fully fitted, the axle travel can be tested/demonstrated by lifting and dropping the axle
Step 9
Fitting the new brake hard lines.
You should have removed the old brake lines in the 1st stage of removing the old suspension parts, or at least moved them out of the way for now. Supplied with the kit are new pre-made extended hard lines, made to pass ‘under’ the axle rather than over it, eliminating any ‘over stretching’ of the flexi line during full drop, or any potential hang-ups with the hard line coming into contact with the inner wing of the car under the same circumstances.
Form the new brake line carefully by hand to follow vaguely the same path as below.
There are designated holes in the lower shock relocators that allow the brake lines to pass through neatly, so use them if you can.
Once the brake lines are in place and connected up, secure the union to the axle using the Jubilee clips and Axle mount tabs. Reuse the original brake line clips to hold the brake hose end in place.
Step 10
Fitting the shock absorbers.
The Sport Gas shocks supplied are the perfect specification and size for this kit, and allow for full range with no upgrade needed. The Shocks secure in place with M10x60 bolts up top and M12x60 Bolts + nuts at the bottom. Fit the shock absorbers as shown, and fully tighten down.
Step 11
Air Lines.
The upper mount has a small hole in the front face that is sized perfectly for a 1/4” air line to pass through.
There are also small 3mm holes alongside the upright, that allow the line to be fitted with plastic P-clips (available as a full fitting kit on our web shop).
Pass the airline through the hole, connect it up to the PTC fitting (this can be tricky, good access helps), and ensure it’s in a safe location, away from sources of heat, movement or potential trapping.
Step 12
Final Bolt Check and Brake bleed.
Bleed the brakes as you usually would when replacing a small section of line. Once done, have a final check over all the parts fitted, ensuring everything is properly tightened down, adjusted correctly and clearing. If you’re unsure of anything, please contact us!
Step 13
Set-up.
Re-fit your wheels and pre-inflate the rear bags to around 90psi. lower the car off of the supports and ensure you’re clear of any obstructions underneath the car. Roll the car back and forwards slightly to allow things to settle. Now let the suspension down fully, allowing the bags to completely deflate and the car to reach maximum drop. There should be no hang-ups, and the car should sit level side-to-side and of course, look great.
Re-Inflate the bags to maximum (100psi) and support the car with a stand or chock (as for the next part you need to get underneath)
Get under the car as best you can (making sure if course the car is otherwise supported) and inspect the bags and the area around them. 100psi in the bags is the maximum they can take to be driven on, and at this pressure, you should expect a near-standard looking ride height. Look at the bags in relation to the axles and spring plates. All clear with no clearance issues? Brilliant. Otherwise, if it looks a little close for comfort, jack the car back up, deflate the bags, and adjust them on the slotted mounts to sit further into the car.
This part is super important! It might be a pain to have to adjust the bags again, but they must never contact or rub anything under their complete operating range! A Rub-free bag is one that will last for years to come.
Step 14
Selecting a good ride height.
With the bags checked and adjusted for clearance if necessary, it's time to start operating the kit normally. The EvaResto Premium kit is designed to be driven low, high, and everything in-between. A good starting point would be around 70psi in each bag. This should give around 3-4” of lift, great ride quality and ground clearance. You may need up to 10psi difference side-to-side to offset the weight of a single driver and no
passengers in order to maintain a level ride height, but this depends mainly on driver weight!
The kit should start to lift at around 35psi and can be driven low. But as a general rule with all air suspension systems, you should not operate the kit in the upper or lower 10% of it’s limits, as this can cause damage to the brackets, the chassis of your car, and the shock absorbers! Get a feel for the kit, and
experiment with different pressures and ride heights, to find what suits your driving style best.
Step 15
Now it’s time to rack up some miles on your newly-bagged VW. We recommend after the first 10, and then 50 miles or so to check over a few things, make sure nothing looks off, or has come loose. Once you’ve completed this period, standard service intervals apply, and your kit won’t need any special treatment, replacement parts or extra servicing for a good many years and thousands of miles.
We always recommend keeping an eye on the underside of your (most likely) 50+ year old classic car, but that’s just common sense ;).
