Not only is a B5 S4 an enthusiast’s dream, but a properly lowered one will certainly turn heads. Dropping the S4 can not only provide a great aesthetic appeal but can also lead to major improvements in handling and cornering, whether just for street fun or dedicated track use.
The B5 S4 was fitted with 4 wheel independent suspension with the front being a multi-link design with four control arms per wheel. The rear was a double-wishbone design meaning the lower control arms are mounted to the subframe. Both the front and rear suspension were fitted with shock absorbers, anti-roll bars, and coil springs. The suspension on these cars is actually very good and performance oriented.
Despite a good factory suspension setup there is still a lot to gain with an upgrade, especially with the B5’s pushing 25+ years old. Whether you are look for stance, street performance, or track use a proper coilover setup will bring provide awesome performance benefits over an old S4’s factory suspension. This guide is going to discuss coilover basics, benefits of coilover upgrades for the B5 S4, and provide a few of our favorite setups for a few different applications.
Audi B5 S4 Coilovers Considerations
Before jumping into our favorite coilover setups on the market, there are many considerations that we feel should assist you in the purchasing decision. Among those considerations are: monotube vs twin-tube, spring rates, dampening or damping, and more. We want to go over these first because it is important to figure out what you are going for with your B5 S4. Are you taking it to the track? Are you wanting to refresh the suspension? Or are you wanting to go for stance? Or lastly, are you wanting to improve the handling on the streets? Our goal is to supply coilover setups for any of those circumstances and provide coilover information to assist you in picking the best coilover setup.
Monotube vs. Twin-Tube
Without going too much into the specifics because it can get quite complicated, we’ll explain the difference between monotube and twin-tube shock designs. Monotube and twin-tube refer to the internals of the coilovers.
Monotube coilovers contain a single “chamber” that houses hydraulic fluid and hydraulic gas. These substances never mix, leading to more precise suspension. These will typically be found in high-performance street cars and track cars. Given the technology of monotube shock designs, they tend to be more expensive.
Twin-tube coilovers have two chambers that individually contain hydraulic gas and hydraulic fluid. Unlike monotube where the substances don’t mix, there are instances that they can mix. This means it causes less precise suspension. However, this isn’t a bad thing. Twin-tubes tend to provide a more comfortable driving experience. These tend to be less expensive than monotube coilovers because they tend to be on daily driver vehicles.
Coilover Spring Rates
Springs are the most important component in the suspension. They control a vehicle’s ability to bounce, absorb bumps, and create a lower center of gravity. Spring rates refer to the amount of weight it takes to compress the springs by 1 inch. Depending on what system you go by, it can be measured as lb/in or KG/mm. Most aftermarket coilover kits have stiffer springs than the OEM suspension. A higher spring rate, 805lb/in for example, is going be to be stiffer and more precise. More than likely higher springs are found on track and high-performance street setups. A lower spring rate, 700lb/in for example, is going to be softer and provide a more comfortable driving experience.
Dampening, or damping, is probably one of the most important considerations when it comes to choosing aftermarket coilovers, especially if a track setup is wanted. This is the control of compression of the springs and how quickly they rebound following compression. Therefore, dampening adjustability is the ability to adjust the levels of damping, or the compression of the springs and rebound. Adjustable dampening is typically found on high-performance street cars or track cars so drivers can customize the suspension for top-tier performance. So what does this mean for the other suspensions that don’t have adjustable dampening?
Those more than likely have fixed dampening. There’s nothing wrong with having fixed dampening because the aftermarket companies research a ton to figure out the optimal dampening levels for any driver. Fixed dampening simply means that the driver can’t adjust the damping.
Coilovers vs. Lowering Springs
This will always be a big topic for discussion because there are people that are heavily for coilovers or heavily for lowering springs. To start off, we don’t see a problem with either. In fact, it goes back to vehicle goals. Lowering springs are good for the budget-conscious driver that is just trying to lower their vehicle. Do we feel that coilovers provide more value? Absolutely. But there also tend to be more expensive. Coilovers allow drivers to customize their driving experience, ride height, and typically come with upgraded shocks and struts. If you are in between the two and don’t know what you should get, we always advise to save up a little longer for some coilovers. We do want to reiterate that we don’t see anything wrong with going with either, we just lean more on the coilover side.
Audi B5 S4 Coilover Benefits
- Improved handling
- Ride height adjustability/Lowers center of gravity
- Dampening adjustability
- More comfortable driving experience
Best Audi S4 Coilovers
When it comes to the “best” coilovers for the Audi B5 S4, we think that is rather subjective. Again, going back to the vehicle goals. There are different goals for different people. Our aim is to provide the best setups for different driving situations. We’ve spent quite a bit of time scrolling through forums and our opinion to determine what enthusiasts are using on their vehicles. Before ordering anything, please make sure it fits your specific B5 S4 application.
1) Raceland B5 S4 Coilovers
Raceland coilovers for some reason don’t have the best rep because of the price. However, the reason they are on the cheaper end is that Raceland eliminates the middleman and goes direct to consumer. Therefore, they are our #1 choice for B5 S4 coilovers because they provide the biggest bang-for-you-buck. The monotube design coilovers offer 2 separate levels, Classic and Ultimo, for different driving styles. If you are looking for a set that provides stance and fits a daily driver, both will work. They provide a 1-4″ drop in ride height, fixed dampening, 805lb/in front springs and progressive spring rates. We do want to preface that these do require stock upper strut mounts and, depending on wheel/tire fitment, may need spacers.
Along with the kit, Raceland provides a 30-day satisfaction guarantee, lifetime warranty, and excellent customer service. Raceland coilovers are the best for daily drivers, period. If we had to recommend which kit to go with, we would advise getting the Ultimo set.
2) ST B5 S4 Coilovers
ST suspensions is a popular suspension brand that has been around for a while and is known for supplying high-performance street setups. The kit features ride height adjustability of 1.6-2.8″, fixed dampening, adjustable spring seats, and more. This set offers a great balance between performance and ride comfort. Along with the kit, ST provides a 5-year limited warranty.
Driver: Stance or Street
Price: $1,044 + Free Shipping
Buy Here: ST x Performance Audi S4 B5 Coilovers
3) BC Racing B5 S4 Coilovers
BC Racing is known for building high-quality racing coilover kits. So, if you happen to have a track B5 S4, these will do the trick. With 30 levels of damping adjustment and performance spring rates, these are as precise as it gets. The monotube design offers a ride height adjustability of 2-3″ which works for many driving conditions.
Driver: Street or Track
Price: $1,195 + Free Shipping
Buy Here: BR Series Audi S4 B5 Coilovers
Audi B5 S4 Coilovers Conclusion
To wrap this post up, we hope the considerations and products we have provided assists in the purchasing decision. Again, not all drivers want their vehicle to ride or perform the same. So to keep it short, if you are looking to refresh the suspension or want a good kit for daily driving, go with Raceland. If you want to customize the set for the streets or take your B5 S4 to the track, you can’t go wrong with BC Racing. Let us know in the comments below what kit you end up with or already have to assist future readers.