First off, let’s address the elephant in the room.
The suspension component known as RV6’s “Rear Camber Arm” is somewhat misleadingly named. In my opinion, it may be more accurate to refer to them as “Rear Lower Control Arms” due to their multifunctionality. While they do offer the ability to adjust camber, it is important to understand the potential implications of using these arms for that purpose alone. One notable concern is the accompanying change in toe alignment, which would require the addition of an adjustable rear toe arm to correct. To avoid such complications, I recommend exploring alternative options from reputable manufacturers like SPC, Eibach, and Hardrace. These aftermarket rear upper camber arms allow for camber adjustments without inducing significant toe changes, while still enabling toe adjustments at the factory locations. This makes them a more practical choice for automotive enthusiasts seeking optimal alignment solutions with minimal hassle.
***Edit: It appears that as of September 2024, nearly a year after my original post, RV6 has renamed their product from “camber arm” to “lower B arm” and now notes that it adjusts toe, without mentioning camber. This is exactly what I thought the product should have been called a year ago. Kudos to them for updating the description to avoid any confusion
Below you can still see how the original URL states “FK8-Rear-Camber-Arm” and how the actual product title is now a FK8 Rear Lower B Arm (Adjusts Toe)
It is worth noting that the significant difference in toe resulting from adjusting camber using RV6 arms is due to variations in the mounting points on the knuckle. The RV6 arm mounts farther out on the knuckle, whereas the upper arm mounts more in the center of the knuckle. So when the upper arm is adjusted, the toe is not greatly affected (see picture below). As well as the fact that the RV6 arm eliminates the factory toe adjustability, necessitating the use of an aftermarket adjustable rear toe arm when dialing in camber solely via the RV6 arm.
In the picture below, you can observe the mounting point of the upper camber arm, indicated by the red circle. Note how it aligns closer to the center line of the knuckle. In contrast, the RV6 camber arm mounting point, represented by the green circle, extends further away from the knuckle’s center line. Consequently, minor adjustments made at the green circle result in significant changes in toe. Conversely, slight adjustments applied at the red circle only yield marginal variations in toe alignment. (Keep in mind that the only picture I could find online does not accurately represent the correct orientation of how the knuckle is mounted. When mounted, the red circle would be in the 12 o’clock position and the yellow line would be straight up and down.)
What all that fancy talk means is, that if you’re seeking an effective way to adjust your rear camber without much hassle, I would advise against investing in the RV6 rear camber arms. Instead, I recommend opting for the widely favored adjustable upper rear camber arm. This versatile solution empowers you to effortlessly adjust your rear camber without relying on any supplementary aftermarket parts. And it offers a reliable and convenient approach to achieving the desired camber adjustment.
The RV6 rear camber arms are an absolute essential for race teams and hardcore enthusiasts who demand the utmost range of camber adjustability, strength, and durability. These arms are designed to work exclusively with aftermarket rear-toe arms, allowing for a perfectly dialed-in suspension setup. In addition to the increased camber adjustability, the RV6 rear camber arms offer a host of other benefits that make them a must-have upgrade. Let me dive deeper into these advantages in the following sections.
For the majority of FK8 owners, a basic adjustable upper camber arm is often sufficient. This is because most FK8 owners only aim to counteract the negative camber that arises from lowering their vehicles. This is because the FK8’s multi-link rear suspension system causes a notable increase in negative camber when the car is lowered, even when only using lowering springs. The average FK8 owner primarily uses their vehicle for street driving or occasional spirited drives in the canyons. As such, they typically prefer to reduce the excessive negative camber and restore their car to its stock camber setting using an adjustable upper camber arm to help prolong tire life.
Next, the average enthusiast will most likely never need to purchase RV6 rear camber arms. And if they do, it will be strictly just to flex by adding some bling that is now visible to any car driving behind them. I’m sure many believe installing them is like installing instant clout. People will see them and think, “This guy must be a serious racer. We should be all over his nuts.” Well, at least that’s why I presume most people buy them. (I could be wrong though)
Okay, my previous statement might have been a bit cheeky. But, I want to emphasize that these upgraded arms truly offer significant improvements over the stock arms. They are especially valuable for individuals seeking to push the limits of their dedicated track cars. However, for those who use their FK8s primarily for daily driving, I must stress that these arms may not be essential. It’s important for car enthusiasts to recognize the specific context in which these upgrades are most beneficial.
Benefits of these arms include:
- Eccentric bolt lock out.
- Made from thicker material for increased arm stiffness and durability.
- The factory rubber bushing is replaced with a spherical bearing.
- Instrumental in achieving large amounts of negative camber.
First off, when it comes to mounting the sway bar to the arm, the design incorporates significantly thicker material compared to the standard OEM arm. This enhanced construction serves a vital purpose – preventing any arm deformation during intense driving scenarios. As a result, you can expect an increase in handling performance, primarily because the sway bar rate remains consistent, ensuring a much more predictable and controlled driving experience.
The arm is constructed with meticulous attention to detail, employing robust gusseting and premium materials. This conscientious approach guarantees a resilient and dependable arm capable of enduring diverse and demanding circumstances. They are stronger and stiffer compared to the factory arms, which have been known to bend and break during road race events.
Threaded locking collar to ensure the arm length doesn’t change once set.
Oh, and without a doubt, they look absolutely stunning as well!
Now you may be wondering if I’m contradicting myself here. After all, I don’t race, and my car is primarily used for holding my garage floor down. However, in my case, I strongly believe that upgrading to these parts was necessary, despite my earlier statement that most FK8 owners can suffice with upper camber adjustments.
As most of you are well aware, pushing your car to its limits in challenging conditions will inevitably expose any weaknesses or deficiencies it may have. I’m fortunate enough to have an FK8 to solely use for tracking and the occasional “spirited drive up a mountain.” As I get closer to breaking into the 56s at Buttonwillow, I’m constantly highlighting the car’s shortcomings and pushing the factory parts to their absolute limits. Every time I’m on track, I fear breaking or bending a rear control arm from hitting a kerb. Keep in mind, that I still have to drive my car 350 miles back home to Las Vegas and go to work at 5:00 a.m. the next day after a track event. I can’t afford to be caught up waiting for a tow back to my house.
Let’s be honest though… The likelihood of someone breaking or bending their rear lower control arm on our chassis is pretty slim, especially for a novice at a regular enthusiast’s track day event. But, is the factory rear lower control arm flimsy as all get out? You bet it is! And when you’re trying to extract every last ounce of performance, that’s when you can really start to become aware of inadequate factory suspension parts. Those inadequacies can cause your car to become unsettled when on the absolute limit, and that can be a recipe for disaster.
Acquiring these arms was an unequivocal decision on my part. With top-notch suspension components in place, I can drive with utmost assurance, knowing I have the same quality parts utilized by racing legends. The inclusion of spherical bearings, reinforced materials, and a rock-solid sway bar mounting system guarantees unwavering performance regardless of the circumstances. As a result, my car’s handling remains consistent, enabling me to completely devote my attention to the joy of driving and relentlessly improve my lap times on the track. And lastly, for me, maybe the biggest selling point was the ability to lock out that eccentric bolt. This helps ensure that my alignment will be the same on my drive home as it was on the way to the track.
Let’s dive into the installation process. By the way, RV6 also provides a comprehensive step-by-step guide on their website. While this may render my HOW TO somewhat redundant, I will focus solely on installing the arms, catering to those who prefer a more visual approach. With that said, let’s get started!
To install these arms, all you need to do is lift the back of your car. Locate the factory jack point at the rear, just to the left of the muffler where my jack is placed.
Once you have raised the car to a sufficient height, place two jack stands, one on each side of the car. Lower the car onto them and remove the jack. Remember, if your car is lowered, jacking up the rear too high may cause the front lip to come into contact with the ground.
With the car in the air, you can now see the factory arm that we will be replacing.
Below, you can see the eccentric bolt that facilitates toe adjustments straight from the factory. As mentioned earlier, these RV6 arms offer a range of benefits, including the ingenious “eccentric bolt lockout” feature that ensures your alignment remains rock-solid, even during rigorous driving conditions. Take a glance at the image below, and you’ll notice how the paint markings from my previous alignment are ever so slightly off. It’s evident that my toe is now slightly out of spec. This issue arose during my last event at Buttonwillow after hitting a kerb too hard and then faced the challenge of driving all the way back home with a slightly misaligned steering wheel – a minor inconvenience that certainly didn’t appease my OCD.
Under normal driving conditions, the subframe bolt is designed to securely hold the arm in place. However, during high-performance track sessions where there are significant amounts of grip and lateral forces, the bolt may struggle to provide enough clamping force, even when tightened to the maximum. This is due to the elongated hole in the subframe, which allows for toe adjustment from the factory but also introduces the possibility of arm movement. It’s important to note that these extreme conditions are typically only encountered on the track. Rest assured, though, for everyday or spirited driving, the factory subframe bolt is more than capable.
Keep in mind, that jumping kerbs or experiencing high amounts of lateral grip on the track is what primarily leads to the factory eccentric bolt slipping.
Here is a zoomed-out picture for reference of where the bolt is located that I’m speaking of.
The next crucial component of the arm assembly is the sway bar mounting bolt. This bolt plays a vital role in securely attaching the sway bar end link to the lower control arm, ensuring optimal stability and handling.
And lastly, the bolt that secures the arm to the rear knuckle.
Sure, here is another view of the arm. Yes, there are only three bolts that need to be removed to swap out the arm, making this a very easy job.
To begin the process, simply detach the sway bar bolt. It is highly recommended to remove the bolt from both the driver’s and passenger’s sides, enabling you to effortlessly flip the sway bar upward and away. This allows for the removal and installation of the arms with utmost ease and efficiency.
To remove the sway bar end links from the rear lower control arms, follow these steps:
- Utilize a socket wrench to easily loosen and remove the 12mm bolts securing the end links. These bolts can be found on both the left and right sides of the vehicle, resulting in a total of 2 bolts being removed. Remember, these bolts are no longer needed and will not be reused.
- It is important to note that the nuts for the end link connections, located on the front side of the OEM lower control arms, are securely welded to the arms and should not be rotated. Be confident in leaving these nuts undisturbed during the removal process.
By following these instructions, you will successfully remove the sway bar end links from the rear lower control arms of your vehicle. Now, simply rotate the sway bar up and out of your way. Pro tip: If your sway bar does not easily rotate upwards, simply loosen the bolts on the sway bar brackets that secure it to the subframe. You only need to loosen them a few turns. DO NOT completely remove the bolts.
Before you proceed any further, it is important to note the location of the two rubber nipples that protrude through the lower control arms. These are known as the spring mounting rubbers, and they are directionally specific for the left and right sides. They must be installed in a specific way.
Take note below: This is my right arm, and you can see the rubber nipples. One is in the center hole, and the other is in the rearmost hole.
Zoomed-out picture of the right side for reference.
Then, on my left side. One rubber nipple is in the centermost hole, and the other is in the forwardmost hole (except mine is missing from the frontmost hole because it seems it somehow pulled itself back through, but it should definitely be in the void where my finger is pointing).
The zoomed-out picture is on the left side for reference.
Next, remove the 17mm bolt that secures the control arm to the rear knuckle. The front side of the control arms uses an integrated threaded nut for the bolt, so no backup wrench is needed. This hardware will not be reused.
It is worth mentioning that if your car is not lowered, there will be some tension from the factory spring pushing downward on the arm. This tension can make it harder to remove the bolt, so if you have any issues here, I suggest using a floor jack and placing it under the arm where it attaches to the knuckle. Then, slowly jack up the jack, this will help relieve some tension from the bolt and make it easier to remove. Be careful though, once the bolt is removed, slowly lower the jack down to release the energy stored in the spring.
But because I am lowered, I can easily remove the bolt, and there is no energy stored in the spring when the suspension is fully dropped.
Now, remove the 14mm bolt that secures the control arm to the rear subframe. Use a 14mm socket on the bolt and a 17mm socket on the nut. To make things easier and prevent the eccentric cam from moving the arm back and forth as you loosen it, hold the 14mm side steady and loosen the 17mm nut. Once the nut is removed, simply use a punch (or a similar item) and a hammer to tap the bolt out.
Once loosened, the arm will simply fall, and the spring will remain attached to it.
The spring magically stays in place because the spring mount rubber nipples hold the rubber spring mount into which the spring is twisted. You will need to twist the spring out of the rubber mount to completely separate the spring and the lower control arm. DO NOT try to remove the rubber spring mount from the arm by pulling/prying the spring, as you run the risk of tearing the rubber spring mount.
The picture below shows my SPC rear upper camber arm that has been installed on my car for years now. And yes, I will be using both upper and lower arms simultaneously.
It is important to note that you can have both upper and lower camber arms installed on your car at the same time. This will not cause any sort of complications. So, if like me, you only want to start with an upper camber arm to adjust the camber, you can do this. And then if you feel the necessity to upgrade to the RV6 rear lower camber arms in the future, that is always an option.
Now, because the RV6 arms are universal and can be mounted on either side, they have three holes for the spring mounting rubber nipples. But remember, you only need to use two holes. Just make sure that you are using the correct nipple orientation for each side.
For reference, the side we just removed was my left side, so I need to ensure I use the forwardmost hole and the centermost hole on the new RV6 arm.
This is what the OEM eccentric bolt looks like when removed. Notice how the bolt and washer are all one piece on the 14mm head side. That’s why I recommend holding the 14mm side steady and loosening the 17mm nut side.
Now we are getting to the good stuff. See below the OEM bolt compared to the RV6 hardware, which includes the eccentric lockout washer, bolt, and metal lock nut.
Subframe where the arm mounts and the factory toe is adjusted from.
Here, you can easily see how the subframe is slotted and allows for slight toe adjustments.
And now you can see how the eccentric lockout washers turn that elongated hole into a fixed hole. This means that no matter how many lateral forces are applied, your alignment will not come out of spec. Basically, you would have to bend your arm or the subframe to experience any alignment changes. I can’t ever see how this would happen though, unless you slid your car sideways into a curb at a high rate of speed.
There are a total of 4 eccentric lockout washers that come in the kit. You are to use two per side, as both the driver and passenger sides of the subframe, forwardmost and rearwardmost, are slotted.
Now we begin installing the arm. As you can see from the picture below, I have already loosely installed the bolt in the subframe, which allows the arm to hang.
Next, take the spring mounting rubber and ensure that you install it with the nipples in the proper holes. Again, for reference, this is my left side arm, and the rubber nipples go into the forward-most and center hole, leaving the rearward-most hole in the arm unused.
Twist the spring into the rubber on the lower arm, then raise the lower arm, aligning the knuckle and arm so that the bolt can be inserted. Do not worry about reinstalling the sway bar end link bolt just yet. You want to make sure you install both RV6 arms (left and right) before installing the sway bar end link bolts.
Below is a great side-by-side comparison picture to highlight the difference in not only the material thickness but also the structural rigidity enhancements of the RV6 arm.
To make installing the sway bar end links less frustrating, take two jacks and simultaneously place them on the knuckles of both sides of the car. Then, evenly jack up each side until the sway bar end links line up with the holes on the RV6 arms. By raising each side evenly, there will be no tension or binding on the end links that could potentially prevent you from aligning the holes.
See how I have jacks on both sides and the suspension is at ride height.
See also how I’m not using the jack on the pretty new red-painted arms. I’m jacking from another part of the knuckle, just slightly in front of the arm where my toe arms mount to.
Left side.
Right side.
And again, a zoomed-out picture to illustrate the whole operation. Notice how my car is still resting on the jack stands. Do not have the car elevated off the jack stands.
Close-up of the left side all reassembled.
Because I still have the stock rubber bushings in the knuckle, I didn’t tighten the bolt securing the arm to it until I had the arms jacked up to ride height. This ensures that when I tighten the bolts, there will be no binding/tension or premature wear of the rubber bushings when the car is sitting on the ground.
But as for the other two bolts (subframe and sway bar end link), because on my car, they are both spherical, I can torque them down with the arm in any position. *Pro tip: if you have stock end links still, they are rubber, and you should ensure they are torqued to spec with the arms in the ride height positions.
Torque specs below:
- Lower Arm to Sub Frame / Inboard Side: 85 lb/ft
- Lower Camber Arm to Rear Knuckle / Outboard Side: 51 lb/ft
- Rear Sway Bar End Links to Lower Camber Arms: 36 lb/ft
The random angle of how the right arm is mounted just for a different perspective.
Overall, the installation is very easy and straightforward. It can be completed in about two hours. However, it will require you to get an alignment, and I don’t recommend driving anywhere except to the alignment shop. Even though the arms come pre-assembled to factory arm lengths from RV6, what you are not accounting for is the eccentric bolt that is no longer eccentric. This means an alignment is a must!
Photo dump!
Pictured below are the tools needed (other than a jack, jack stands, and tools to remove the wheels).
- Regular-sized 3/8 ratchet.
- A longer 3/8 ratchet for increased leverage is needed for the 17mm bolts/nuts.
- 17mm combination wrench.
- 12mm 3/8 socket.
- 14mm 3/8 socket.
- 17mm 3/8 socket.
- 6mm hex socket.
RV6 also includes its own custom wrenches for use on the jam nut and camber adjustment nut.
As mentioned at the beginning of this article, these arms are designed to allow complete control of a full range of camber adjustability. They are best used on cars looking for more than 2.5 degrees of negative camber.
When it comes to optimizing the performance of a front-wheel drive car, adding negative camber to the rear wheels is a game-changer. This adjustment has a notable impact on acceleration and top speed, with the reduced contact patch minimizing rolling resistance and drag. Additionally, the rear brakes become more sensitive, allowing for easier locking of the rear wheels. However, it is crucial to fine-tune the brake bias for front-wheel drive vehicles with excessive negative camber at the rear by way of pad compound or bias valves. Keep in mind that tire longevity may be compromised due to the smaller contact patch. Together, these factors contribute to an enhanced driving experience and improved overall performance.
Having negative camber on the rear wheels of a track car is an absolute must for achieving maximum grip during intense cornering. By cleverly adjusting the alignment, you can optimize the contact patch and empower your vehicle to handle like a Formula 1 car. With negative camber applied to the rear wheels, you can push the limits and exploit the car’s roll to its fullest potential, extracting gobs of traction and superior performance. It’s worth noting that you can be more aggressive with negative camber on the rear wheels, as they don’t bear the responsibility of transmitting power. This means that a stiffer rear end, combined with generous negative camber, allows you to approach corners at higher speeds, maintain exceptional grip, and effortlessly carry that speed through the turns. In some extreme cases, front-wheel-drive cars have been known to lift their inside wheel due to the sheer rigidity of the rear end. To combat this, substantial negative camber is employed to fully harness the immense contact patch and ensure optimal handling. So, when it comes to mastering the track, don’t underestimate the power of negative camber on those rear wheels – it’s the secret weapon behind unparalleled performance.
Remember, these arms only work in conjunction with an adjustable toe arm. Currently, I am running the Wunderladen racing rear toe arms, and you can read all about that installation by clicking the link below.
The RV6 camber arms are absolutely perfect when paired with an adjustable toe arm. When making adjustments to the camber using the RV6 arm, it is essential to consider the significant requirement for toe adjustability. The striking aesthetics of these RV6 rear arms are simply unparalleled. However, it is crucial to keep in mind that as you begin to modify your vehicle, the need for complementary parts to ensure optimal performance becomes increasingly essential.
That is why I firmly maintain that these components can prove to be more than necessary if you simply use your car for daily commuting. It is indeed true that once you have your suspension precisely aligned to specifications using the RV6 arms, you won’t have to worry about getting an alignment for a long time. However, if you are not consistently seeking to alter your car’s handling on various tracks by making constant adjustments to your alignment and striving to shave off precious tenths from your lap times… then you are not fully exploiting the tremendous advantages provided by the boundless adjustability of these parts.
It’s easy to get caught up in all the fancy features and upgrades available, especially as a beginner. However, I want to assure you that you don’t necessarily need all of these advanced parts right away. In fact, starting with adjustable upper camber arms and lowering springs can still provide a great experience, even on the track.
Personally, I was able to achieve a sub-2-minute lap at Buttonwillow using just adjustable upper camber arms and lowering springs. So, please don’t feel overwhelmed or pressured to invest in all the additional adjustable arms and spherical bearings right from the start. Take your time, gradually explore, and learn more about your car’s behavior on the track. That way, you can make informed decisions about which upgrades will truly benefit you in the long run.
I want to emphasize that my intention is not to discourage anyone from purchasing these arms or to pass judgment on those who simply desire them for their aesthetic appeal. I completely understand the allure of wanting something that looks cool, and I respect individual preferences. I do, however, feel compelled to highlight the fact that these arms can be quite expensive. Having been in similar situations myself before, I know how challenging it can be to determine which components are truly necessary to fully engage in certain activities. To put it simply, unless you are frequently tracking your car or solely using your FK8 as a track car, these arms may be considered a bit excessive. I hope this perspective helps in making an informed decision that aligns with your needs and preferences.
Without a shadow of a doubt, the RV6 rear camber arms are the epitome of excellence and an absolute must-have for every track enthusiast. With their unmatched performance and precision engineering, these extraordinary camber arms are sure to set you apart from the competition. Whether you’re an avid track racer or simply crave the admiration of others at car meets, these arms will undoubtedly surpass your highest expectations.
Thanks again to all you awesome folks who visit the blog to read my random ramblings that try to teach but end up sounding like a rant. I like to lay it out straight for you. I want to give you some real talk about what’s really going on behind all that social media glitter. Brace yourself, ’cause some of what I say might not be your cup of tea. But hey, sometimes the truth stings a little, right? As always, if you have any questions, comments, concerns, hate, or want to argue. You can reach me at Billy@functiontheory.com, on Instagram @Functiontheory, or simply comment on the post below and I will get back to you.