How To CHECk OR RESETTING
wheel travel range
Due to MCA Suspension putting more time into each product/setup than most brands, the bottom wheel travel range is already set correctly, so checking/resetting the wheel travel range is usually only required for the below reasons.
1. Drop knuckles or custom/modified knuckles are fitted.
2. More than a 15mm change in TYRE diameter (not wheel diameter) from factory.
3. Significantly modified fender/wheel arch area.
Special note for Drift Cars:
It’s good to check the wheel travel range for most drift cars even if drop knuckles aren’t fitted just so you can be confident that your tyre won’t foul on your fender/chassis at any point through the wheel travel range. In addition to the front wheel being straight as you check/set the wheel travel, you should check the wheel through lock as well, but usually only as the front of the tyre turns outwards for opposite lock. Full suspension compression and lock with the front of the tyre turning inwards is not a common situation.
THE BASICS
A shockabsorbers compressed length is the part that controls where the wheel travel stops as the wheel goes up into the wheel arch. The bottom mount on the shockaborber is the part to adjust when the compressed length is something you want to change.
The thing that determines what compressed length the shockabsorber should be, otherwise referred to as the limiting factor for compression travel, changes depending on the type of vehicle it is and the modifications it might have. Examples of limiting factors for compression travel are the tyre contacting the fender or wheel arch, a suspension arm contacting the chassis, ball joints or brake lines going tight,
the tyre going so far up that the body/chassis of the car would then be able to bottom out on the ground, etc.
THE PROCESS
STEP 1:
Get one end of the vehicle up on jack stands, remove bumpstop and spring. To check and/or set the compressed length (controlled by the bottom mount position), it’s best to work on one end of the vehicle at a time and have that end of the car up on jackstands. Remove the shockabsorber and remove the spring and bumpstop, then refit the shockabsorber to the car.
STEP 2:
Make sure the swaybar is connected. Make sure the swaybar is connected on the side you’re testing as sometimes it can be the travel limiting
part. Depending on the car, you may find it best to remove the shockabsorber from the other side of the car so that the swaybar isn’t resisting the next steps.
STEP 3:
Jack the suspension assembly and wheel/tyre up to see where it’s currently set. Ideally you want the shockabsorber to fully compress (no chrome shaft visible) just as or just before another part of your suspension assembly or wheel/tyre limits the travel. Examples of this were listed
above in “The Basics”. This means that the shockabsorber is allowing the suspension assembly and wheel/tyre to use as much space in the wheel arch as it can, but not let it go too far to cause any damage or issues.
To do this you want to use a trolley jack or similar to jack the suspension assembly and wheel/tyre up into the wheel arch and see what happens. You should do this with and without the wheel/tyre fitted so that you can determine which part is the limiting factor for suspension travel, as having the wheel and tyre on can sometimes make it hard to see the other parts of the suspension and assembly.
STEP 4A
The shockabsorber could be setup with too little compression travel.
If the shockabsorber fully compresses before there’s any contact issues from the suspension assembly or the wheel and tyre, try to determine roughly how much further you think it could travel before there is any issues and adjust the shockabsorber’s compressed length shorter that amount. Do this by winding the bottom mount up onto the threaded body more. To move the bottom mount you will need to first make sure that it’s locking ring is loose. Typically this locking ring is set quite tight from MCA Suspension as in most cases the bottom mount doesn’t need to be moved.
STEP 4B
The shockabsorber could be setup with too much compression travel.
If the suspension assembly or wheel/tyre cause the upwards travel to stop before the shockabsorber fully compresses, then you should lengthen the shockabsorber’s compressed length by the same amount that there is chrome shaft showing at the travel limited position. This is done by winding the bottom mount down off the threaded body.
STEP 4C
Maybe it’s already set perfectly.
If the shockabsorber fully compresses a few millimetres before the suspension assembly or wheel/tyre contact another part of the car, for example the wheel/tyre is about to contact the fender, or a suspension arm is about to contact the chassis, then there is no need to make any adjustments as this is what you’re looking for.
STEP 5
Take wheel to fender measurements at full compression, ride height and full extension.
Once you’re happy that it’s all setup so that the wheel travel range uses as much compression travel as possible, while the wheel and tyre is at full suspension compression, measure the bottom of your rim up to your fender, this measurement can be handy in the future to help know how much compression travel you have from a particular ride height. Then using the trolley jack, let the wheel and tyre drop away from the fender to your desired ride height position. Measure the bottom of rim to fender again and note this measurement. Then let the wheel and tyre drop all the way down until the shockabsorber is fully extended and measure the bottom of the rim to fender again and note the measurement.
STEP 6
Make sure you have at least 50mm wheel extension from ride height.
It’s important that the difference between ride height and fully extended isn’t less than around 50mm. Most cars in most scenarios will use a maximum of 50mm extension from ride height. If the extension difference is less than 50mm, you should lengthen the shockabsorber by winding
the bottom mount down off the threaded body by the amount of additional extension that’s required. This will sacrifice some upwards travel, but in this case you most likely will already have plenty upwards travel and it’s ok to lose a bit to make sure you have enough extension travel.
NOTE: More than 50mm wheel extension from ride height is no problem, it’s just about making sure you have the minimum required.
STEP 7
Reassemble the shockabsorber and move onto the other end.
Once you’re happy with your compressed and extended lengths, put the bumpstop and spring back on the shockabsorber, re-install it and make the same adjustments to the other side unless you think that you should do a manual thorough check of the other side also, but usually you can just copy them side to side. Now you can move onto the other end of the vehicle.
If you have any questions please contact us
