Should I get FOX DSC Adjusters?
December 10, 2019
Fox offers a Dual Speed Compression Adjusters (DSC) on their shocks and coilovers. This will allow you to manually adjust the high and low speed compression valving on the shocks. This is a great feature that provides many advantages which we will go over below.
Low Speed Compression
What is Low Speed Compression?
Low Speed Compression on a shock refers to the speed at which the shaft compresses into the shock body. Slow speed compression occurs when a vehicle is cornering, braking, accelerating and driving over large rolling bumps. Because shocks have to react to a bump, they move slowly before moving fast which means low speed compression can also be felt on high speed bumps, especially if the bumps are small and frequent (washboard) and also if the valving is too stiff.
When would I need to adjust Low Speed Compression?
-If you find the vehicle feeling bouncy or bottoming out on big rolling bumps, you should stiffen up the Low Speed Compression on your DSC.
-For better handling, and less brake dive the Low Speed Compression adjuster should be tightened.
-If the vehicle is rough on washboard roads, or small bumps, you should soften up the Low Speed Compression Adjuster on your DSC.
-Low speed adjustments on the DSC are very effective and can be the most useful adjustment on the DSC.
High Speed Compression
What is High Speed Compression?
High Speed Compression happens when the shock compresses very quickly (not just because you are driving quickly). High speed compression occurs when hitting things like curbs, speed bumps, whoops etc..
When would I need to adjust High Speed Compression?
-If the suspension and tires are slamming through and bottoming out on hard hits you need to increase high speed compression.
-Due to the construction of the DSC internal parts, high speed compression adjustments are not as distinguishable or noticeable as low speed adjustments.
Do shocks with DSC adjusters need special valving?
Yes, the main piston valving and DSC need to work together to create the overall stiffness of the shock. The DSC acts as an additional restriction point in the oil flow path. The DSC can only make the shock stiffer, so the main valving needs to be tuned softer for maximum performance. If the main piston is substantially too soft, or a little bit too stiff, the DSC wont give you an ideal adjustment range. The DSC adjuster only affects compression and can’t fix harshness or softness based on rebound damping.
AccuTune Offroad specializes in tuning Fox Shocks with DSC adjusters. We will tune a DSC shock for just about any vehicle driving on any terrain. Contact us today to see what we can offer you! (424) 377-0808 or Sales@accutuneoffroad.com
When would someone want a DSC adjuster on their shocks or coilovers?
Fox DSC adjusters allow you to stiffen the shocks to compensate for added weight, different terrain or more aggressive driving. Trucks & SUV’s that tow or carry heavy loads will benefit from DSC adjusters because they can be setup with a soft tune for daily driving and the DSC’s can be adjusted to a stiffer setting when carrying a load.
Overland vehicles can benefit from DSC’s because their weight and terrain fluctuate a lot. Unloaded on the street, you may want a soft tune for a smooth ride. Off-road you may want more control and comfort depending on the type of terrain (nuisance rocks vs whoops) and load (empty vs fully loaded).
For the weekend warrior who daily drives their vehicle, but also wants to go fast off-road, or drive through difficult terrain at high speed, DSC’s will be very beneficial. On the street, with max tire pressure, you may want to soften up the tune for most comfortable ride. Off-road you can air down tires to soak up smaller rocks and then stiffen up the DSC adjusters to help control the vehicle from bottoming out. DSC Adjusters are very common for daily driven vehicles like Toyota Tacomas, 4Runnes, Ford F150 and Raptors.
For solid axle vehicles that have a tall center of gravity, on road the suspension will need a lot of stiffness to control the chassis. Off-road, they can be setup softer to soak up the small rocks and gravel on the trail. Lowering tire pressure will also help with little bumps and rocks.
Off-road race cars benefit from DSC adjusters because they make some tuning changes extremely simple and improve the function of the shocks. For experienced teams they can allow for easy adjustments during the race or between tracks.
With just a few turns on the DSC, you can really improve the ride quality needed for driving on the street, off-road or towing.
When would you not need DSC adjusters on your shocks?
DSC’s are not a necessary upgrade for customers who will not need or want to adjust them, and are not required for many applications. If your vehicle is mostly a daily driver and you do very little off-roading, you may not need DSC’s. If your vehicle is very consistent in weight and you are more concerned with comfort than performance you probably don’t need DSC’s. The DSC adjuster is simply a nice feature that allows you to get the most out of your Fox shocks.
Can you upgrade shocks to have DSC adjusters?
Yes, you can upgrade shocks or coilovers to have DSC adjusters. However, you should really consider getting DSC adjusters on your shocks the first time around to save money. Upgrading to a DSC requires the entire remote reservoir to be replaced with a cylinder specifically designed to work with the DSC. In addition to a new remote reservoir with DSC, the shock should also be revalved.
12” Fox 2.5 Coilover = $519.95
12” Fox 2.5 Coilover with DSC = $669.95 (+$150 for DSC)
Adding a DSC later = $330.00/per shock for parts + labor and shipping costs.
Making Adjustments to your Fox DSC Adjuster
High and low speed compression adjusters may have been shipped at random settings, so it’s best to get them all in the same setting. Start with adjusters all the way open and drive the vehicle (in a safe location at a safe speed) to get a baseline of how soft it can be.
Start with Low Speed Compression:
-1 click in of high speed is required before adjusting the low speed
-Tighten low speed compression until handling is acceptable
-Two clicks for big changes, one for small changes
-Low speed compression clicks can be hard to feel on the dial
-The adjusters get more sensitive the closer they get to fully closed
-Don’t close it all the way before adjusting high speed
Adjust High Speed Compression Last:
-Tighten high speed compression until big bump performance is acceptable
-This adjustment is not always necessary
-When low speed knob is near fully closed this can act like a fine adjustment
-High speed compression clicks can be difficult to make due to a stiff adjuster
DSC Tech Tips:
-It is normal for the DSC’s to remain all the way open on street tunes, so you can compensate for added weight.
-If your vehicle is too stiff and the adjusters are all the way open, it may be necessary to revalve the main piston.
-If your vehicle is too soft with adjusters near the fully closed setting, it may be necessary to revalve the main piston.