How To Install Adjustable Coilover Springs

Many people have coilovers installed on their automobile to improve their treatment and functioning just are not setting them up correctly and can accept many handing problems due to setting them upwardly incorrectly. Incorrect setup is due to a massive amount of mis-information within the industry which is not helped past the fact that dissimilar coilover manufacturers likewise recommend the incorrect techniques to setting the coilover up correctly.

This article details the correct way to set up a coilover that has two points of ride height adjustment and for coilovers with a single bespeak of ride height adjustment. Coilovers with 2 points of adjustment have damper body height adjustment and jump base height aligning like in the image below.

Dampers with a unmarried point of adjustment have jump base of operations elevation adjustment only. Both methods let the damper to be gear up correctly. Having a damper with 2 points of peak adjustment helps to fine tune the crash-land to droop ratio of the damper stroke on your machine so is a preferable option for fine tuning the handing of your track auto.

Preload

Before roofing how to set the ride pinnacle of the damper, the effects of pre-load must first exist covered. Pre-load is another expanse with lots of mis-information surrounding it and usually does non be like many people think it does.  Nearly cars use a linear rate curl bound, therefore, if the spring is compressed, the spring rate does not change. Therefore, if yous compress a linear roll spring, with a rate of 10kg/mm, by placing 100kg of mass on information technology the rate of the spring volition yet be 10kg/mm and it will shrink by 10mm. If you lot add another 100kg to a total of 200kg directly to the spring then it will compress by another 10mm so on.

The deviation between the outset and the 3rd jump in the above diagram is that spring 3 now has stored energy and has the desire to extend. Still, when you place the mass of your machine on leap 1 it will also carry a very similar corporeality of stored energy making the "preload" effectively redundant.

If you begin compressing the leap and so much that the coils begin to bind at total droop then this will take an effect on the spring rate due to having inactive coils which will change the spring rate. In this extreme case, you should wait to either installing shorter springs of the aforementioned spring rate or removing the helper springs if they are present.

The just scenario where pre-load does exist is in a variable charge per unit curlicue spring. This is a spring with sections of different rates that changes in spring charge per unit every bit the bound compresses. This style of spring is a much rarer application and the amount of compression at ride height will have an impact on the jump charge per unit at each corner. However, for about applications, and for the vast majority of motorsport, linear rate springs are used.

Setting Damper Travel

When setting upwards the damper on the auto you demand to make sure that once the automobile is sat at ride height, there is an adequate amount of bump and droop travel in the damper in order to optimise performance. As a rule of pollex, for almost cars, the damper should be gear up and then that one time at ride height, 2/3rds of the available travel is for bump and 1/3^rd of available travel is for droop.

In order to achieve this, the first step is to remove the spring from the damper and to measure the length of the damper shaft that protrudes from the damper trunk when fully extended. Then fully shrink the damper and measure the length of the damper shaft that protrudes over again. Adjacent, use the beneath equation to calculate the full corporeality of damper travel available:

With damper travel calculated you can now calculate the amount of droop travel for your damper:

With your droop travel calculated you tin now calculate crash-land travel for your damper using:

Next, yet with the spring removed from the coilover, install the damper onto the car properly. If you race your car in a championship and so information technology is highly likely that you lot will have front and rear ride top limitations in the rules and regs. If this is the case then set your chassis to the minimum ride heights allowed front and rear using jacks, beam stands or wood etc and install the wheels.

Next, adjust the damper using the damper torso superlative adjustment to set the bump to droop ratio calculated higher up. In the blitheness beneath we have highlighted the damper rod to show the droop travel (carmine) and crash-land travel (dark-green) that we desire to accept from our damper. Using the damper body adjustment we need to gear up the top of the damper body on the line between the blood-red and green zones equally this will mean that we take the correct amount of bump and droop travel available from the damper.

Notice in the above animation how the top mountain is staying in the same position, showing that the ride height is not changing at this point. The simply aspect being altered is the position of the damper piston inside the damper body showing how constructive the damper body adjustment is at altering the bump and droop ratio.

Next with the bicycle still installed, jack the bicycle up all the way until the crash-land stop in engaged. At this point hopefully your bike will not be in contact with your body piece of work or your bike arch. If it does not contact then you can move on to installing your spring and fine tuning the ride pinnacle in the next department.

If your wheel does interfere then you accept to make some decisions. 1 solution is to raise the ride height of your automobile by the amount of damper travel left before the crash-land stop is engaged. This is often a sensible option if you are in a situation where you are just running your car far too depression. If you lot have set your car to see the ride summit requirements of a title and then a solution is to cut away the inner arch or fit wider body piece of work to prevent interference and allow the wheel to recess into the body work.

If the tyre is hitting the outer wheel arch so check your slant settings too as if you haven't got circular to aligning the machine even so you lot might have it set up to positive camber or not enough negative camber at ride height and this could be causing the interference.

If none of the above situations are available so you might have to remove some of the crash-land travel using the lower damper height adjustment. This is an absolute concluding resort as information technology will reduce the amount of bump travel and increase the amount of droop travel upsetting the ratio calculated earlier.

Setting Ride Height

With the crash-land and droop range gear up correctly on the damper you tin now remove the coilover and re-install your gyre jump on your damper. With the complete coilover re-installed to your automobile yous tin can now lower the machine back down to the ground to sit down on the floor. With the mass of the car now sat on the spring and damper, your ride height will almost definitely be in a unlike position to your fix ride height before due to the spring compressing. This is to be completely expected.

You lot can now use the lower jump platform to prepare the ride height of the car. Turning the lower jump platform upwards with raise the ride tiptop of the car and turning the lower spring platform down the damper will lower the ride peak of the car. The aim is to use the lower spring platform to raise or lower the base of operations of the leap until the ride height that y'all set before based upon regulations, experience, calculations or data is achieved.

In the blitheness below it shows our damper from before with the cherry-red and green zones on the damper rod. We accept now installed our spring which is compressed with vehicle mass upon it. You can come across that the damper piston is now sat lower in the body than we want. As we raise the leap platform y'all can see how the damper piston is rising back to where we desire it to be merely this time the ride tiptop is likewise being raised (shown by the lifting top mount). Once the ride peak is set using the leap platform, the damper volition be back in the correct position with the correct bump to droop ratio.

Don't worry if y'all compress the leap when doing this as it volition not affect annihilation. The only time to have concern is if yous are compressing the spring so much that the coils are binding and becoming inactive. In this case install a shorter spring of the same stiffness.

Once the ride height has been set, jack the car back up, lifting the wheel off the floor and then that the damper is at total droop. At this signal check that the spring is still captive between the upper and lower mounts. If information technology is then lock off the lower spring perch collars equally the damper is now correctly set. If it is loose so you volition need to install a helper leap to keep the principal spring captive nether full droop. If you do need to install a helper spring then you lot volition need to lower the spring perch by the same distance equally the compressed thickness of the helper spring. Once installed and adapted, re-cheque your ride height as it might demand a further tweak of the leap platform.

With this terminal aligning complete y'all have at present fix your coilover correctly and it is set to utilise.

Doubts

Many people have been taught how to fix up a damper in a totally unlike way. This is due to a lot of mis-information surrounding the topic, some of this information even coming from the coilover manufacturer and being recommended on documents that they provide with the coilovers. However, this is an unfortunate example where, although the quality of the production is very good, information technology is effectively a copy of some other product on the market and the background noesis hasn't been at that place on the production line when making these products and providing fitting guides etc. This doesn't mean that the products aren't upwardly to standard, it simply means that the information provided with them is sometimes incorrect.

If you lot look at brands such as KW or AST they often sell coilovers without the damper body ride height adjustment and just take the bound platform adjustment. This is because, they pattern an platonic ride height for the application the damper is suited for, effectively pre-setting the bump and droop ratio for the car and pre-determined ride height. The spring platform can then be used to adjust the ride height to accommodate your personal requirements. Ohlins ofttimes supply their coilovers with the damper torso adjustment as it is an added bonus being able to melody the crash-land and droop ratio of the damper for your set up up.

As an instance of why non to use the damper body to conform your ride height, imagine a situation where y'all have a 26Kg jump installed on your coilover and yous are at present moving to a 8Kg leap of exactly the aforementioned unsprung length. This is an extreme example but helps to show the reasoning. When moving to the softer jump with all height settings in the same place as before, the car will at present sit lower as the softer spring will compress by a greater amount than the stiffer spring. The way in which the automobile has lowered is by compressing the damper and pushing the damper piston farther into the damper body (reducing bump travel). Therefore, if you were to now use the damper torso to heighten the machine back up, this reduced bump travel would still remain every bit the jump would still compress by the same corporeality at ride height.

However, if you raised the ride peak by using the lower spring platform, in one case the softer spring was installed, you would have raised the automobile and pushed the damper piston up within the damper body, increasing the bump travel back to where it should be fix. This style, yous have achieved the ride top change and yous have set the damper ratio back to where it should be.

Source: https://suspensionsecrets.co.uk/coilovers-installing-and-setting-ride-height-correctly/

Posted by: hemphillboying.blogspot.com

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