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Why This $300 Upgrade Transforms Your Scion FR-S

Investing roughly $300 in Whiteline sway bars for your Scion FR‑S (also known as the Subaru BRZ or Toyota GT86) is one of the most cost‑effective chassis improvements you can make. The stock sway bars are designed for a comfortable street ride that prioritizes understeer as a safety margin, leaving a lot of cornering potential untapped. Replacing them with Whiteline’s adjustable units dramatically reduces body roll, sharpens turn‑in response, and allows you to dial in the balance between understeer and oversteer to suit your driving style. This article provides a complete, step‑by‑step installation guide along with the technical background you need to get the most out of this upgrade.

Understanding Sway Bars and Their Effect on Handling

A sway bar (also called an anti‑roll bar) is a torsion spring that connects the left and right sides of the suspension. When the car corners, the bar resists the difference in suspension compression between the inside and outside wheels. A stiffer bar increases resistance, reducing body roll and keeping the tires more evenly loaded, which improves grip. Whiteline’s bars are typically 20‑23 mm in diameter – larger than the stock 16‑19 mm bars – and they feature multiple adjustment holes that let you fine‑tune the effective stiffness.

With the stock sway bars, the FR‑S feels planted but rolls noticeably in sharp corners, causing the inside rear wheel to lift under heavy cornering (a trait enthusiasts call “the Miata wiggle”). Whiteline bars keep the car flatter, allowing you to carry more speed through corners without triggering understeer. The adjustable end links also eliminate the rubber bushing slop that deadens steering feedback.

Front vs. Rear Bias

Whiteline offers both front and rear sway bar kits. Many owners start with the rear bar only to reduce understeer and promote a more playful rotation. Others install both to get the maximum flat cornering. The front bar stiffens the chassis and improves steering precision, but if you go too stiff on the front you can reintroduce understeer. The rear bar is the primary tool for dialing out understeer and inducing controlled oversteer. Whiteline’s adjustable end links let you choose from three rates: soft, medium, and stiff. A common starting point is soft front / medium rear, then tuning from there based on track or autocross feedback.

Choosing the Right Whiteline Kit

For the Scion FR‑S, the recommended kits are:

  • Front sway bar: Whiteline BTR22Z – 22 mm diameter with three adjustment holes. Includes polyurethane bushings and adjustable end links.
  • Rear sway bar: Whiteline BTR23Z – 20 mm diameter with three adjustment holes. Also includes polyurethane bushings and adjustable end links.

You can purchase them separately or as a pair. Expect to pay $150–$170 each. A complete set with both bars runs about $300–$340. Be sure to verify compatibility with your FR‑S model year (2013–2016 are identical; later models may have minor differences in end link design).

External link: Whiteline BTR22Z front sway bar product page

External link: Whiteline BTR23Z rear sway bar product page

Tools and Materials You’ll Need

Before you begin, gather the following items. Having everything on hand will prevent frustrating trips to the hardware store mid‑project.

  • Whiteline front and rear sway bar kits (with bushings and end links)
  • Floor jack and two heavy‑duty jack stands
  • Socket set with 10 mm, 12 mm, 14 mm, 17 mm, and 19 mm sockets (deep 14 mm recommended for end link nuts)
  • Combination wrenches: 10 mm, 12 mm, 14 mm, 17 mm, 19 mm
  • Torque wrench (0–150 ft‑lb range)
  • Penetrating fluid (e.g., WD‑40 or PB Blaster) – for seized bolts, especially on older cars
  • Lithium grease or Whiteline’s supplied grease for bushings
  • Blue Loctite (medium strength) for end link and chassis bolts
  • Safety glasses and mechanic’s gloves
  • Trim removal tool (plastic pry bar) – helpful for removing underbody panels
  • Shop rags and a drain pan (in case of coolant or oil drips – unlikely but good practice)

Optional but recommended: A creeper or work light to see under the car. Also, anti‑seize compound on adjustable end link threads for future adjustments.

Installation: Front Sway Bar

Work on one end of the car at a time. The front sway bar is more involved because of the engine crossmember and limited clearance.

Step 1 – Raise and Support the Front End

Park on a level surface. Chock the rear wheels. Use a floor jack to lift the front of the car by the front crossmember (just behind the oil pan). Place jack stands under the factory lift points on the side rails. Lower the car onto the stands. Verify stability before crawling underneath.

Step 2 – Remove the Underbody Panels

The front sway bar is partially hidden by a plastic underbody panel. Remove the six or seven 10 mm bolts and two push‑pins that hold it in place. Set the panel aside. You may also need to remove the small panel covering the sway bar mounts themselves.

Use a 14 mm socket and a 14 mm wrench to hold the nut while turning the bolt on the top end link connection (the stud goes through the control arm). The lower connection is similar. If the joint spins, apply penetrating fluid and wait a few minutes. Remove both end links completely.

Step 4 – Unbolt the Stock Sway Bar Mounts

The front sway bar is held in place by two U‑bolts (or bracket assemblies) near the center of the car. Use a 12 mm socket to remove the two bolts on each side. Keep the brackets and bolts – they may be reused if the Whiteline kit uses its own brackets. In most cases you will reuse the factory brackets but install Whiteline’s polyurethane bushings in place of the stock rubber ones.

Step 5 – Remove the Stock Sway Bar

Slide the stock bar out from the driver side (left) of the vehicle. It helps to turn the steering wheel slightly to create clearance. If the bar is stuck, gently tap it with a rubber mallet. Do not force it against the steering rack or brake lines.

Step 6 – Install Whiteline Bushings and Mounts

Apply a generous amount of the provided grease to the inside of the new polyurethane bushings. Slide them onto the Whiteline bar at the correct location (check the notches on the bar). Place the bar in position, then reinstall the factory brackets. Torque the bracket bolts to 35 ft‑lb (factory torque spec). Do not overtighten, as polyurethane bushings need a little compression but not crushing.

Thread the Whiteline end links through the control arm and bar. The kit includes two sets of spacers – use them to center the end link in the slot if needed. Apply a drop of blue Loctite to the threads. Tighten the nut to 35 ft‑lb while holding the stud with a hex key (some versions have a hex fitting). Repeat for both sides.

Step 8 – Set the Adjustment Holes

Choose your hole position on the end link. For street/aggressive, start with the middle hole (medium stiffness). The softest hole (longest distance from the bar) provides the least resistance and is good for daily driving. The stiffest hole (shortest distance) is for autocross or track use. Make sure both sides are set identically.

Step 9 – Lower the Front and Check Clearance

Remove the jack stands and lower the car. Turn the steering wheel lock‑to‑lock and check that the end links and bar do not contact the frame, control arms, or brake lines. If clearance is tight, add a small washer spacer to the end link top to push it away from the control arm.

Installation: Rear Sway Bar

The rear sway bar is easier to access and can often be installed without removing the wheels, but you’ll still want the rear of the car lifted for access.

Step 1 – Raise the Rear End

Jack up the rear by the differential pumpkin, then place jack stands under the rear side lift points. Ensure the car is level.

Step 2 – Remove the Stock Rear Sway Bar

The stock rear bar sits above the exhaust mid‑pipe. Disconnect the end links using a 14 mm wrench and socket. They are often corrosion‑prone; apply penetrating fluid and let it soak. Remove the two mounting bracket bolts (12 mm) and slide the bar out from the passenger side (right). You may need to unbolt the exhaust hanger temporarily to create room – loosen the two rubber hangers with a flathead screwdriver and let the exhaust hang slightly lower.

Step 3 – Install Whiteline Bar and Bushings

Grease the new bushings and slide them onto the Whiteline bar. Position the bar in the factory brackets. Torque the bracket bolts to 22 ft‑lb (spec for rear). Reinstall the exhaust hanger if removed.

Connect the rear adjustable end links. Again use blue Loctite and torque to 35 ft‑lb. Set the adjustment holes symmetrically. A popular autocross setup is soft front / medium rear for a neutral balance. For more oversteer, stiffen the rear or soften the front.

Step 5 – Lower and Inspect

Lower the car, then push down on the rear bumper to settle the suspension. Recheck all bolts. Re‑torque after 50 miles to account for bushing settling.

External link: FT86Club forum: Whiteline sway bar installation tips and owner reviews

Post‑Installation Setup and Testing

Alignment Check

Installing stiffer sway bars does not change static alignment, but if you lowered the car or added other suspension components, you should get a professional alignment. Pay special attention to front camber and toe. A common street/track alignment for the FR‑S is -1.5° front camber, -1.0° rear camber, 0.08” total toe‑in front, and 0.10” total toe‑in rear. This setup works well with Whiteline bars.

Test Drive Procedure

Take the car to an empty parking lot or quiet road. Drive in a gentle circle at 15 mph and feel the roll reduction. Then accelerate through a corner exit – the rear should rotate slightly if you set the bar to stiff. If the car understeers (pushes wide), move the rear end links to a stiffer hole. If it oversteers too eagerly (snap oversteer), soften the rear or stiffen the front. Adjust one hole at a time and test again.

Expected Performance Gains

  • Flat cornering: Body roll reduced by 40–60% compared to stock.
  • Sharper turn‑in: Front end responds more immediately to steering input.
  • Greater tire grip: More consistent contact patch under load.
  • Improved steering feel: Less slushiness from rubber bushings.
  • Adjustable balance: Tailor understeer/oversteer to your driving style or track conditions.

Long‑Term Maintenance and Wear

Polyurethane bushings can squeak over time if not lubricated. Whiteline supplies grease with the kit, but you may need to reapply every 12–18 months depending on climate. Remove the end link bolts, lift the bar slightly, and inject fresh grease with a needle‑tip applicator. Also inspect end link bolts for rust or loosening – re‑torque them annually.

If you drive in heavy rain or off‑road (unlikely for an FR‑S), consider applying a light coat of anti‑seize to the adjustable end link threads to prevent galling. The sway bar itself is powder‑coated and should resist corrosion, but touch up any chips with paint to avoid rust.

Frequently Asked Questions

Will Whiteline sway bars make the ride harsh?

No – the bar only affects roll stiffness, not vertical compliance. The ride remains mostly unchanged over bumps, though you may feel a slight increase in jounce through the bushings. It is still a comfortable daily driver setup.

Yes. The stock end links have rubber bushings that will fail under increased load from a stiffer bar. Whiteline includes heavy‑duty adjustable end links that eliminate this weak point.

Can I install only the rear bar?

Absolutely. Many owners find that installing just the rear bar is enough to reduce understeer and make the car more playful. You can always add the front bar later.

Whiteline recommends 35 ft‑lb for the end link nuts. Do not exceed 40 ft‑lb, as the stud can break on rough roads.

External link: Video walkthrough: Whiteline sway bar installation on Scion FR‑S (by Speed Academy)

Conclusion

For about $300, a set of Whiteline sway bars transforms the Scion FR‑S from a fun but floaty coupe into a precise, confidence‑inspiring corner‑carving machine. The installation is straightforward with basic tools, and the ability to adjust stiffness means you can evolve the setup as your skills grow. Whether you’re daily driving, autocrossing, or tracking, this upgrade should be near the top of your list. Pair it with a good alignment and performance tires, and you’ll have a car that punches far above its price point. Get the Whiteline kit, follow the steps here, and enjoy a dramatically improved driving experience.