The Honda Acty Kei Truck is one of those little workhorses that punches way above its weight. Compact, agile, and incredibly versatile, the Acty has become a cult favorite not only in Japan but also among enthusiasts worldwide who appreciate the charm and practicality of these mini trucks. Whether you're using it for farm work, urban deliveries, or just cruising as a weekend project truck, there’s plenty of potential to unleash with the right performance upgrades.
In this article, we'll break down the best performance upgrades you can do for your Honda Acty. Whether you're focused on speed, handling, comfort, or utility, there’s an upgrade path for every kind of owner. And if you’re hunting down quality parts, shops like Oiwa Garage are worth checking out for hard-to-find components tailored specifically for Kei trucks.
1. Engine Upgrades for More Power
Let’s be honest: the stock Honda Acty isn’t going to win any drag races. With a 660cc engine designed for efficiency rather than excitement, it’s zippy enough for city use but lacks punch. Here are a few ways to add some real get-up-and-go.
A. Performance Air Intake
Upgrading to a high-flow air intake can help the engine breathe better, increasing horsepower and throttle response. Brands like HKS and K&N offer universal filters that can be adapted to the Acty’s engine bay. Cooler, cleaner air going in means a more efficient burn and slightly better power output.
B. Exhaust System Upgrade
A less restrictive exhaust system reduces backpressure and can give your Acty a surprising bump in performance. A cat-back exhaust or custom muffler setup not only improves performance but also gives the truck a more aggressive sound. Just be mindful of noise regulations in your area.
C. ECU Tuning
While the Acty’s ECU is relatively simple compared to modern vehicles, piggyback systems or reflashing can optimize fuel and ignition maps for better performance. This is especially beneficial when paired with intake and exhaust upgrades.
D. Turbocharger Conversion (Advanced)
For those who want to go all-in, a small turbo setup can be adapted to the Acty’s engine. This isn’t for the faint of heart or the casual DIYer, but for the seasoned tuner, it’s the ultimate way to transform the truck into a street-legal mini missile. Keep an eye on heat management and make sure the drivetrain can handle the added power.
2. Suspension Upgrades for Better Handling
The Honda Acty wasn’t built for spirited cornering, but that doesn’t mean it can’t be improved. Upgraded suspension not only makes driving more enjoyable, it also enhances safety.
A. Lowering Springs or Coilovers
Upgrading to lowering springs or full coilover systems will reduce body roll and improve overall handling. You’ll get a lower center of gravity, which improves stability without sacrificing ride quality too much. If you’re aiming for that JDM stance, this is a go-to modification.
B. Upgraded Bushings
Swapping out old rubber bushings for polyurethane ones helps tighten up the feel of the suspension and steering. This relatively inexpensive upgrade makes a big difference, especially on older Acty trucks where bushings have degraded over time.
C. Sway Bars
Adding or upgrading sway bars (also called anti-roll bars) helps distribute weight more evenly in corners. This keeps your Acty flatter in the twisties and improves response in quick maneuvers.
3. Brake System Enhancements
A performance build isn’t complete without adequate stopping power. While the Acty is light, once you’ve added speed and possibly load weight, better brakes become essential.
A. Upgraded Brake Pads
High-performance brake pads offer improved bite and fade resistance compared to stock. Brands like EBC or Project Mu offer options that work well with Kei trucks.
B. Stainless Steel Brake Lines
Switching to stainless steel braided brake lines improves pedal feel and reduces line flex during hard braking. It’s a minor upgrade that provides a more connected feel.
C. Big Brake Kit (if available)
Some enthusiasts retrofit larger calipers and rotors from other Honda vehicles. This is a more involved mod but worthwhile if you're pushing the Acty’s performance envelope.
4. Transmission and Drivetrain Improvements
Making power is one thing, but putting it to the ground efficiently is just as important. Drivetrain upgrades can make your Acty feel snappier and more responsive.
A. Lightweight Flywheel
Installing a lightweight flywheel allows the engine to rev more freely, improving throttle response. It’s especially noticeable in the lower gears and can make city driving more fun.
B. Clutch Upgrade
If you’re adding power, a heavy-duty clutch becomes essential. Performance clutch kits can handle the increased torque without slipping and ensure longer life under aggressive driving.
C. Limited-Slip Differential (LSD)
A LSD drastically improves traction in wet or uneven conditions. It’s particularly useful if you plan on off-roading or if you’ve added serious power and need to prevent wheel spin.
5. Tires and Wheels for Performance and Aesthetics
Often overlooked, wheels and tires can make or break how your Honda Acty feels on the road.
A. Lightweight Wheels
Upgrading to lightweight alloy wheels reduces unsprung weight, making acceleration, braking, and handling more efficient. Stick to smaller diameter wheels to maintain that Kei truck aesthetic.
B. Performance Tires
High-quality tires offer better grip, shorter stopping distances, and improved road feedback. Choose tires suited to your use—whether that’s daily driving, off-roading, or track use (yes, some people track their Acty!).
C. Wheel Spacers
Wheel spacers can improve the stance and widen your track, which helps with stability. Just be careful with size—too aggressive and you risk rubbing or stressing the suspension components.
6. Interior and Driver-Centric Mods
Performance isn’t just about horsepower—it’s also about how the truck feels to drive. Some small interior mods can enhance your overall driving experience.
A. Performance Steering Wheel
A smaller aftermarket steering wheel offers a sportier feel and more control. Just ensure it maintains compatibility with your horn and safety requirements.
B. Short Shifter
Reducing the throw of your shifter gives quicker gear changes and a more connected feel to the transmission. Combine it with a weighted shift knob for even better tactile engagement.
C. Gauge Cluster Upgrades
Installing a tachometer (if not factory equipped) or additional gauges like oil temp and voltage help you monitor your Acty’s vitals—especially useful if you've done engine upgrades.
7. Exterior Mods with Performance Function
While aesthetics are subjective, some exterior modifications also add real performance benefits.
A. Front Lip or Air Dam
These can improve aerodynamics and give your Acty a more aggressive appearance. Some options are universal, so a little customization might be required.
B. Lightweight Body Panels
For extreme performance builds, consider swapping heavy steel parts with fiberglass or carbon fiber. Doors, hoods, and even beds can be replaced to cut weight.
C. LED Lighting
Upgrading to LED headlights and fog lights not only enhances night driving but reduces draw on the electrical system.
8. Utility Upgrades for Practical Performance
Remember, this is still a truck at heart. Performance can also mean being better at hauling, carrying, and surviving rough work.
A. Bed Liners and Utility Racks
Heavy-duty bed liners protect your Acty from abuse while utility racks expand its hauling capacity. This makes your upgraded Acty both fun and functional.
B. Skid Plates
If you’re doing any off-roading or trail driving, skid plates can protect the undercarriage from rocks and debris. They’re a must-have for rugged use cases.
C. Power Inverters or 12V Mods
Enhancing your electrical system with power inverters or auxiliary lighting gives your Acty more utility in outdoor or work settings.
9. Where to Get the Parts
When it comes to sourcing reliable parts for a Honda Acty, quality and compatibility are critical. While some performance parts can be found through major aftermarket brands, the Kei truck world is a niche market—especially outside Japan.
That’s where specialized shops come in. Oiwa Garage is one such name that Kei truck owners trust for authentic and performance-ready parts. Whether you’re looking for engine components, suspension kits, or aesthetic accessories, they offer curated options that fit the unique layout and specs of the Honda Acty.
Final Thoughts: Building Your Ultimate Acty
Upgrading the Honda Acty is less about building a race car and more about creating a truck that’s dialed into your needs and your personality. With the right parts and a little creativity, you can turn this humble Kei truck into something that surprises everyone—yourself included.
Whether you're going for boosted performance, tighter handling, or simply a more refined driving experience, the Acty has the bones of a project that can keep growing with you. From its compact platform to its unmistakable character, it’s a blank canvas that rewards ingenuity and effort.
So, grab your tools, make a list, and start wrenching. Your dream Acty is just a few mods away.