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JB4 Tuner for Subaru WRX, Ascent, Legacy, & Outback
- Price
- $582.99
Optional Device Connection: None
📞 Questions before ordering? Call us at
475-227-5381
Power gains of up to 50hp to the wheels on a stock vehicle
The JB4 is the most advanced and highly featured tuning system for your Subaru 2.4L 4 cylinder turbo. Power gains are up to 50hp to the wheels (70hp crank) on a completely stock car on pump gas, and gains with ethanol mixtures and bolt-on parts are even higher.
The JB4 features a simple plug & play installation harness for easy installation & removal and includes many features not found with any other tune. Including on the fly map switching from your phone/tablet instead between factory and various performance maps, boost limiting by gear for improved traction in lower gears, progressive water/methanol support, built-in data logging, built-in code reading, and much more.
The JB4 features a simple plug & play installation harness for easy installation & removal and includes many features not found with any other tune. Including on the fly map switching from your phone/tablet instead between factory and various performance maps, boost limiting by gear for improved traction in lower gears, progressive water/methanol support, built-in data logging, built-in code reading, and much more.
Wirelessly connect the JB4 to your Bluetooth 4.0 compatible iOS and Android device via the JB4 Mobile connect kit or your Windows laptop with the BMS data cable. Both options allow you to record and analyze vehicle and tuning data, change JB4 performance maps, and update JB4 firmware as we release free newer versions with updates, more powerful maps, and new features under development. A separate JB4 Mobile app purchase is also required.
Subaru JB4 FEATURES & BENEFITS
• Power gains of up to 50hp to the wheels on a stock vehicle
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom JB4 Subaru tuning software and up to 8 maps for various fuel and modification levels
• Ethanol (E85) compatible tuning maps
• Able to read/delete fault codes
• View and record up to 30 different gauges/engine parameters in real-time with the JB4 app.
• Boost by gear in 1st, 2nd, and 3rd can be controlled via the JB4 app for a perfect launch
• Compatible with JB4 Mobile for smartphone logging, tuning changes, and adjustment
• The JB4 offers a lot more performance, functionality, and safety than your average performance chip
• Quick Plug & Play Installation
• CANbus OBDII integration offering unrivaled tuning features and performance
• Improved performance over non-integrated chip tunes
• Runs as smoothly as stock, this is how your vehicle should have come from the factory
• Compatible with all driving modes
• Fuel economy unchanged during normal driving
• 91 octane fuel or better required for performance gains
• Not VIN locked and can be removed without a trace and resold down the road
• Includes the rugged JB4 billet aluminum enclosure for protection
• Made in the USA
• Free USA Shipping
• 5 year warranty
Vehicle Fitment
• 2022-Present Subaru WRX 2.4L 4 cyl. Turbo
• 2019-Present Subaru Ascent 2.4L 4 cyl. Turbo
• 2020-Present Subaru Legacy XT 2.4L 4 cyl. Turbo
• 2020-Present Subaru Outback XT 2.4L 4 cyl. Turbo
What is a JB4?
The JB4 is a plug & play tune available for turbocharged vehicles. The JB4 tuner installs between your car's sensors and the DME/ECU (computer) and manipulates vehicle performance through these connections making your vehicle much faster. While it's not the only tuning system that operates this way the JB4 separates itself from the competition with much more advanced connection points and processing including CANbus, fuel & spark control, Bluetooth to your smartphone, and a variety of innovative and advanced features not possible with any other system. BMS regularly publishes free mapping and firmware updates adding performance and features as ongoing development allows. In addition, the JB4 system is not VIN-locked to your vehicle and can quickly be removed and swapped between cars or resold at a later time. Often imitated but never duplicated the JB4 has been the gold standard in plug and play turbocharged performance tuning for over a decade.
Questions?
WE HAVE ANSWERS
How long til' I get my order?
Small items arrive to you in under 1 week
Larger products like full suspension kits must ship freight and can take 1-3 Weeks
Are Installation Instructions Included?
Instructions are included for most parts that require any sort of knowledge to install.
Here's what to do if your parts come WITHOUT instructions:
1. Some parts are genuinely common sense on how they get installed
2. If you can't figure it out on your own, YOUTUBE IS YOUR FRIEND! Our founder started this company from learning how to build headlights off a YouTube Video
3. If there are no videos on YouTube, or instructions anywhere on Google then please CALL OR EMAIL US and we will guide you through or get you instructions from the manufacturer
4. Doing installs on your own is always fun, but sometimes, it isn't. Always consider having your parts professionally installed
ALWAYS CONSIDER US. We sold you the parts, let us install them at THE LAB in Connecticut. We offer enclosed and open cross country transportation.
Of course you won't want to spend thousands on transportation to install lug nuts or emblems but if you are spending a LOT of money on parts, you may just want to send the car our way
What is your return policy if the part doesn’t fit or isn’t what I expected?
If the part was NOT installed, we accept returns within 14 days of delivery.
If the part WAS installed (or attempted installation), we cannot accept a return.
Do your parts come with a warranty?
All parts come with Manufacturer Warranty! Each manufacturer has different warranties so we suggest reading up on their warranty policy before ordering.
I found a better price somewhere else, can you beat it?
YES! If you come across a competitor with a lower advertised price than us, we will BEAT it by at LEAST 1%. Please contact us with proof of the lower priced product.
Do you give out discounts or sponsorships?
NO! We do not give out discounts or do sponsorships. You can get 5% OFF your first order by signing up for text & email notifications. OR just wait until our BLACK FRIDAY Sale that happens once a year.
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Store Information
Customer Support : 9:00 AM To 5:00 Pm (Mon To Fri)
Address: 150 Universal Dr , North Haven , CT 06473
*Location Not Open to the Public*
Email: sales@legendsautoparts.com
Phone: (475) 227-5381
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