2JZ Engine Swap into BMW E46 Chassis for 900HP Monster

Understanding the 2JZ Engine

The Toyota 2JZ engine has reached an almost legendary status among performance enthusiasts. This inline-6 engine was manufactured by Toyota Motor Corporation from 1991 to 2005 in both naturally aspirated and twin-turbocharged configurations. In stock form, it produced up to 280 horsepower, but when modified, it can reliably produce over 1000 horsepower.

The 2JZ is often referred to as one of the most overbuilt and over-engineered motors of all time. Its iron block, forged steel crankshaft and connecting rods, and thick cylinder head deck makes it capable of handling tremendous power outputs. This combination of robust design, performance potential, and affordability is why the 2JZ has remained popular for engine swaps for over two decades.

2JZ Engine Variants

There are three main variants of the 2JZ engine:

• 2JZ-GE - A 3.0 liter naturally aspirated engine producing up to 220 horsepower.
• 2JZ-GTE - A 3.0 liter twin-turbocharged engine producing up to 280 horsepower from the factory. This is the most popular variant for tuning.
• 2JZ-FSE - A direct injected naturally aspirated engine producing up to 225 horsepower. Only available in the Japanese market.

Why Swap a 2JZ into a BMW E46?

BMW E46 models came with a range of capable inline 6-cylinder engines from the factory. However, most topped out at around 250 horsepower in stock form. For many owners, extracting substantially more power from these motors often requires forced induction, internal modifications, and an engine management system recalibration.

In contrast, the turbocharged 2JZ engine is renowned for its ability to produce huge horsepower numbers with basic upgrades to the turbo, fuel system, and tuning. Additionally, the smooth power delivery and iconic sound of a 2JZ swap makes for an exciting driving experience.

By transplanting this bulletproof Toyota powerplant into an E46 3-series chassis, you get the best of both worlds - a reliable high horsepower engine in a sharp-handling rear wheel drive coupe or sedan.

Benefits of the 2JZ Swap

• Huge tuning potential - Can reliably produce over 800whp on stock internals
• Proven reliability - Engine design handles immense power
• Relative affordability - Lower cost than building up BMW engine to similar power levels
• Retains 50/50 weight distribution - Improves handling balance

Important Considerations

While the 2JZ engine has found its way under the hood of everything from Mazda RX7s to Nissan 240SXs, each platform presents its own set of swap considerations. Here are a few key factors to think through with an E46 project.

Engine Fitment

The 2JZ engine is larger than BMW's M50 and M52 motors. This means modifications need to be made to engine mounts, transmission crossmember, hood, and firewall for proper fit. Oil pans, steering racks, and exhaust routing may also need to be addressed. Thankfully, several companies offer swap kits and components specifically for 2JZ-powered E46 builds.

Wiring & Electronics

As the 2JZ engine was never offered by BMW, a custom wiring harness adapter needs to be fabricated to mate the engine to the chassis. This allows communication between Toyota and BMW electronics for proper vehicle integration. Additionally, an aftermarket engine management system is recommended for tuning the motor.

Cooling System Upgrades

When aiming for high horsepower numbers, upgrading the E46 cooling system is a must. Items like dual pass radiators, electric fans, oil coolers, and even meth injection kits are commonly added to keep engine temperatures in a safe range under hard use.

Achieving Over 900WHP

The owner of the M140i mentioned at the beginning of this article was able to extract over 900 wheel horsepower from their 2JZ-swapped vehicle. This level of power requires extensive modifications including:

• Forged internals - Pistons, rods, main studs/girdle
• Large twin turbo kit - Capable of 30+ PSI of boost
• Upgraded fuel system - High flow pumps, injectors, and regulator
• Custom tuning - Properly dialing in air/fuel ratios and timing maps
• Engine management system - Aftermarket ECU for fine tuning

A strengthened transmission and driveline upgrades are also necessary to contend with the massive torque output. With the right combination of parts, custom fabrication work, and precise tuning - insane four-figure horsepower numbers can be achieved with the legendary 2JZ.

FAQs

What is the typical horsepower output of a 2JZ swapped E46?

With supporting mods, a well tuned 2JZ swapped E46 can reliably produce 600-800 horsepower to the wheels. With forged internals and big turbo kits, output can exceed 900WHP.

Do I need to upgrade the transmission on an E46 2JZ swap?

The E46 M3 transmission is a popular option for 2JZ swaps to handle the extra power. Some opt for beefed up automatic transmissions if going for high power figures exceeding 800hp.

Will my stock E46 fuel system work with a 2JZ engine?

An aftermarket fuel system upgrade is highly recommended. You will typically need upgraded fuel pumps and injectors properly sized to match your horsepower targets.

What engine management is best for a BMW E46 with a 2JZ swap?

Aftermarket programmable ECUs like Haltech, Syvecs, or AEM are popular choices. This allows for precise tuning and control of the motor beyond what BMW's stock DME can provide.