Thinking about grabbing some tomei headers frs owners can't stop talking about is basically a rite of passage for anyone with an 86-platform car. If you've spent any time driving a stock Scion FRS, you already know the deal. It's a fantastic chassis with great balance, but that engine? It's got a personality quirk that most of us find pretty annoying: the infamous torque dip.
Installing a set of Tomei headers is usually the go-to solution for fixing that dip while finally giving the car a voice that matches its aggressive looks. But before you go dropping several hundred bucks on a box of shiny pipes, it's worth breaking down what you're actually getting and why Tomei has become such a household name in the FT86 community.
Dealing with the Infamous Torque Dip
If you've ever tried to merge onto a highway or power out of a tight corner in a stock FRS, you've felt it. Around 3,500 to 4,500 RPM, the car just sort of hits a wall. The power stops building, the engine sounds a bit strained, and you're left waiting for the needle to climb past 5,000 where the fun starts again.
That's the torque dip, and it's mostly there for emissions and fuel economy reasons from the factory. The stock manifold is pretty restrictive, and that's where the tomei headers frs setup comes into play. By swapping out that bulky factory cat for a high-flow, catless manifold, you're allowing the FA20 engine to breathe much more freely.
The result isn't just a few extra horsepower at the top end. The real magic happens in that mid-range. With a proper tune and Tomei headers, that flat spot almost completely disappears. The car feels more linear, more predictable, and honestly, a lot more like the sports car it was always meant to be.
The Big Debate: UEL vs. EL
When you start looking at Tomei's catalog, you're going to run into a choice: Unequal Length (UEL) or Equal Length (EL). This is where the community gets divided, and it really comes down to what you want out of your driving experience.
The UEL "Subie Rumble"
Most FRS owners go for the Tomei Expreme UEL headers. Why? Because of the sound. Since the piping for one side of the engine is longer than the other, the exhaust pulses reach the collector at different times. This creates that iconic, deep, rhythmic thumping sound often associated with WRXs.
If you want your FRS to sound mean and have that classic boxer character, the UEL is the way to go. Performance-wise, it's great for filling in that torque dip, though it might sacrifice a tiny bit of peak high-end power compared to an EL setup. For most daily drivers, that trade-off is totally worth it for the sound alone.
The EL Precision
On the other hand, the Tomei Equal Length headers are designed for pure efficiency. All the pipes are the same length, which means the exhaust flow is perfectly timed. This usually results in a smoother, more "exotic" sound—think higher-pitched and more consistent.
Track guys often prefer the EL headers because they squeeze out every last bit of power at the top of the rev range. You won't get the rumble, but you'll get a very refined, surgical engine note that sounds amazing at 7,000 RPM.
Build Quality and What's in the Box
One thing I've always appreciated about Tomei is that they don't cheap out on the extras. When you open the box for your tomei headers frs kit, you aren't just getting the metal. They usually include the gaskets, hardware, and even some thermal wrap.
The welds on these things are beautiful. They're made from high-grade stainless steel (SUS304), and they're surprisingly light compared to the heavy cast-iron factory manifold. Handling them side-by-side, you'll realize just how much weight you're shaving off the front of the car. It's not a huge amount in the grand scheme of things, but every pound counts when you're dealing with a car this light.
The inclusion of heat wrap is a big deal, too. Because these headers sit right underneath the engine and near the oil pan, things can get pretty hot. Wrapping them helps keep the engine bay temperatures down and keeps the exhaust gas velocity up, which is a win-win for performance and longevity.
The Reality of the Installation
I'm not going to lie to you—installing headers on an FRS isn't the hardest job in the world, but it can be a bit of a literal headache if you're doing it on jack stands in your driveway.
You're going to be working in some tight spaces. Getting the old manifold off usually involves fighting with some rusted bolts, especially if you live somewhere with salted roads. My best advice? Soak everything in PB Blaster or WD-40 the night before. Your knuckles will thank you later.
Once the old one is out, the Tomei unit usually slides right in. The fitment is generally spot-on, which is one of the reasons people pay the "Tomei tax" instead of buying a cheap knock-off from eBay. You know it's going to bolt up without you having to pry things into place or hammer on your subframe.
One thing to keep in mind: if you're going catless (which these are), you're going to get a Check Engine Light (CEL) almost immediately. The car's computer sees that the primary cat is gone and thinks something is wrong. Which leads us to the most important part of this mod
You Absolutely Need a Tune
Please, don't just bolt on your tomei headers frs and call it a day. While the car will run, it won't run well. Without a tune, the ECU doesn't know how to handle the increased airflow. You might even find that the car feels sluggish or "jerky" in certain spots because the air-fuel ratios are all out of whack.
Most people go with an OpenFlash Tablet (OFT) or a custom Ecutek tune. A Stage 2 tune is specifically designed for catless headers. Not only does it delete the CEL, but it optimizes the timing and fueling to actually take advantage of the new headers. This is where you really feel the torque dip vanish. If you're budgeting for the headers, make sure you're budgeting for the tuning solution, too. They're a package deal.
Living with the Sound
Let's talk about volume for a second. If you have a stock exhaust (the "catback" part) and you just add Tomei headers, the car actually stays pretty civilized. It gets a bit deeper and louder when you step on it, but it's totally fine for daily driving.
However, if you already have a loud catback—like a Tomei 60R or 80R, or maybe an Invidia N1—adding these headers is going to make the car loud. Like, "wake up your neighbors three houses down" loud. Cold starts specifically become very aggressive. The FA20 does a high-idle warm-up that sounds like a lawnmower on steroids when you have catless headers.
You'll also notice a bit more mechanical noise coming from the engine bay. Since the walls of the stainless steel headers are thinner than the thick factory cast iron, you can actually hear the exhaust valves opening and closing. It's a cool, raw sound, but it's something to be aware of if you're used to a whisper-quiet cabin.
Is it Worth the Investment?
At the end of the day, buying tomei headers frs enthusiasts love is one of the most impactful things you can do for the car. It's not just about the numbers on a dyno sheet; it's about how the car feels when you're driving down a backroad.
The FRS is all about driver engagement, and nothing adds to that engagement like a better power band and a great soundtrack. You're fixing the car's biggest flaw while giving it a more aggressive soul. Sure, it's an investment, and yes, you have to deal with tuning and maybe some extra noise, but the first time you hit 4,000 RPM and the car actually keeps pulling, you'll know you made the right choice.
If you're looking for that perfect balance of Japanese engineering, solid build quality, and that unmistakable rumble, it's hard to beat what Tomei has put together for this platform. Just be ready for everyone at the gas station to ask you what's under the hood.