Let’s Tech!: Tanabe Sustec Rear Stabilizer Install
It’s all in the name; “Anti-Roll Bar”. Although, more often refereed to as a sway bar, the purpose of these bars is to reduce the amount of body roll in your vehicle during fast corning, or often times irregularities in the driving surface. If you have experience with FF vehicles, you’ll know that one of the most difficult challenges to overcome is the car’s propensity to understeer; meaning the car has a tendency to turn less sharply than is intended. If you’ve experienced it on track, understeer can be scary – much harder to control than oversteer. One of the easiest ways to combat this is through the use of these sway bars.
In this case, we will be installing a Tanabe Rear Anti-Roll Bar on my project car, the Dog Fight 2000 Honda Civic (TSB018R). There are a few unique characteristics of the Tanabe bar that set it apart from the rest. Let’s see what they are, and how a rear sway bar can increase the enjoyment in your driving; whether on track, or for recreation.
*Keep in mind that the following write-up and install was done by a competent mechanic. If you are unsure of what you are doing, or do not feel confident in doing this sort of install on your own, it is recommended by myself and NDF that you seek professional assistance. Remember to put safety first in any situation involving vehicles, maintenance and driving. Always obey all road rules and traffic laws.
A deciding factor in going with the Tanabe rear sway bar was that they are made from a material called ‘chromemoly’. The uniqueness of chromemoly’s strength is such that even with a smaller diameter anti-swaybar, the resistance is much greater than a standard steel anti-swaybar that is larger in diameter. On top of that, Tanabe’s stabilizers are hollow; all of which add up to a lighter, stronger product. If you know me personally, you’ll know that I have a saying when it comes to racing; “grams make ounces, ounces make pounds.” I am very adamant about saving weight, as in my case, weight = power.
This particular bar’s outer diameter is 20mm. While Tanabe has designed the bar to work with the OEM subframe components, I have decided to upgrade to adjustable heim-joint type end-links for my install. This is a personal preference of mine that gives me more adjustability in the long run, however it is not necessary.
A closer look at one of the ends of the bars with end-links loosely attached.
Now, back to the technical stuff. So we now know what an anti-roll bar does, but how does that effect the cars behavior, and how does it achieve this change?
Well, by keeping the car more level in turns (reducing roll), the tires are able to do their job more effectively. In a turn, there is going to be more force applied to the outside tire as opposed to the inside tire. As a result, there is going to be more displacement of the outside suspension/tire than there will be on the inside. This is generically defined as body roll. Essentially it can render the inside tires almost useless.
In our case, by adding a rear sway bar, we are able to counteract this displacement. The bar acts as a link, connecting the left and right sides of the suspension independent from the shocks/springs. Because each pair of wheels is cross-connected by a bar, the combined operation causes all wheels to generally offset the separate tilting of the others, and the vehicle tends to remain level through sharp corners.
This use of a larger diameter rear sway bar can be used to our advantage in a FF car, as it will help lift a rear wheel when cornering hard, in order to overload the other wheel on the axle, limiting understeer.
In this picture you can compare the new Tanabe bar, with an OEM rear sway bar that is 13mm in diameter. You can also see the difference between the OEM endlinks and the upgraded adjustables. Notice that that Tanabe bar is very similar in shape to the OEM equivalent? This helps tremendously in the clearance of various exhausts, as you will see in the coming pictures. I’d like to attribute this to the bar being designed and produced in Japan; something you won’t find in other bars and something that I adhere to very closely when looking to purchase a product.
During this install, I also decided to try out a new lateral lock piece. These two clamps tighten around the sway bar on the insides of the D-Brackets to prevent shifting or sideways movement of the sway bar under lateral loads (severe cornering). My car is a track car and it sees constant abuse in this sense. I’m not too sure how much a sway bar actually moves within the brackets (I’m guessing very minimal), but I was curious to see if any difference was felt. Again, this piece is not necessary.
Here you’ll see the D-Brackets I have on my car are slightly different than what most will use, and we’ll see why in a second.
Before you wrap the bushings around the bar, be sure to apply a liberal amount of lubrication or grease to the insides. You can see the brackets here roughly in place, along with the loosely tightened lateral locks.
The reason I use a larger D-Bracket is because I also have a subframe brace installed on my car that has the D-Bracket positions spaced more so than the OEM subframe(you can see I circled them in the picture). While on most applications you will be fine without a brace, as I mentioned, this car sees the track quite often and in the sake of playing it safe I purchased a brace. The larger diameter sway bar puts much more force on the subframe giving it the possibility to tear over an extended period of time. With the Tanabe bar being 20mm, you will more than likely be safe if you do not run a brace.
Once you position the bar approximately equel length, go ahead and loosely tighten the D-Brackets to the subframe. You won’t want them all the way tight yet because you’ll need to shift the bar slightly in order to install the endlinks into the rear lower control arms.
The control arms I use have various positions to place the endlinks in. I chose a position that would yield an increase roll stiffness for the rear of the car. OEM lower control arms will have a designated place for the endlink.
As I mentioned previously, a common problem with running an aftermarket sway bar is exhaust clearance. You won’t run into this problem with the Tanabe bar. The shape of the bar parallels that of an OEM one, as opposed to running a more straight across design, which allows you to run a variety of aftermarket exhausts without running into any fitment problems. Coincidentally, the exhaust piping pictured here on my car is from an old Tanabe Hyper Medallion.
Once everything is in position, go ahead and tighten down the D-Brackets, as well as the bolts to the endlinks. The torque specs should be 22 foot pounds for the endlink nuts, and 20 foot pounds for the D-Brackets.
The night after the install I took a spirited drive around a specific area of roads I like to drive on and I could immediately feel an increase in the cars ability to rotate in cornering. I used to run no rear sway bar, and heavy front aero to help the car’s rear rotate through turns, however, with the addition of the rear sway bar, the negation of understeer is very apparent. This is easily one of the most cost efficient ways to improve the handling of your vehicle.
I hope this post was of assistance to some, and unlike some posts on forums or what not that disappear after a few years, this post will always be here. If you need any help, or have any other questions, feel free to email me via the contact page.
I’ll be starting a new series of posts following the rebuild of my time attack car – starting this weekend, this Civic is going under the knife to be completely rebuilt to compete in the 2015 season of time attack. Stay tuned!