Ultimate Guide to Twin Turbo Manifolds for the 2JZ Engine

Introduction to 2jz Twin Turbo Manifolds

Two turbochargers and a twin scroll manifold is a popular performance modification choice for the legendary 2JZ engine. Pairing this inline-6 engine with twin turbos enables very high horsepower potential while maintaining good low-end torque and driveability.

In this guide, we'll look at what a twin scroll manifold is, why pairing twin turbos can benefit the 2JZ platform, important considerations for choosing a twin turbo manifold, and provide examples of popular manifold setups that have enabled 1000+ horsepower reliably on street and race 2JZ builds.

Understanding Twin Scroll Turbo Manifolds

A twin scroll turbo manifold physically separates the flow from each side of the engine into its own housing or "scroll" within the turbocharger. This helps keep exhaust pulses as independent as possible for optimized spool and power production.

Some key benefits of a twin scroll setup include:

• Improved turbine spool rates - cylinders don't interfere with each other during overlap
• Quicker boost response throughout the RPM range
• Increased power output potential
• Easier pairing with larger twin turbo options
• Tuned specifically for the firing order of the 2JZ straight 6

Why Twin Turbos Fit The 2JZ So Well

By design, the 2JZ is extremely overbuilt and responds very well to boost and power adders. The factory engine can reliably make over 600 to 700 horsepower on a single turbo setup.

When building the 2JZ for 800+ horsepower though, the compressor and exhaust flow capabilities of a single turbocharger start to become limiting factors. By switching to an efficiently designed twin turbo manifold setup, there is much more room for max power growth.

Some benefits of upgrading to twin turbos on a high horsepower 2JZ include:

• Enable 900 to 1500+ horsepower capability
• Near instant spool and max boost by ~3500 RPM
• Capable of high horsepower at high RPM - VTurbos are common
• Divide airflow and load between turbos
• Run larger compressor wheels than a single turbo allows

Choosing the Right Twin Turbo 2JZ Manifold

There are a few critical factors to consider when selecting twin turbos and a matching turbo manifold for your 2JZ engine build:

• Turbine housing A/R ratio - target around 1.00 A/R for street or 0.81 A/R for dedicated racing use
• Compressor wheel inducer and exducer sizes
• Turbine wheels - look for forged wheels on high HP builds
• Twin scroll design - evenly separates exhaust pulses
• Tuned for 2JZ firing order and performance RPM range
• Tight clearance options for hood clearance issues
• Turbine outlet size and v-band options
• High quality welds and materials - stainless steel recommended
• Integrated high-flow wastegates
• Oil and coolant line fittings/ports

It's crucial that your manifold properly supports the target air flow capabilities and performance parameters of your twin turbo setup.

Popular Twin Turbo Manifolds for the 2JZ Engine

While custom one-off manifolds can be fabricated by a skilled shop, you'll want a well engineered and designed manifold to meet big power goals reliably. Here are some of the most popular options commonly used in high horsepower street and race 2JZ turbo builds.

BorgWarner EFR Equipped Dual Manifold

BorgWarner's latest EFR series turbochargers have become extremely popular in race and high power street builds alike. An EFR twin scroll manifold setup takes full advantage of these turbos' high flow capabilities and quick spool characteristics.

Typical EFR twin setups on the 2JZ use either the 9174 or 9180 compressor options paired with 1.05 or 0.96 A/R divided T4 turbine housings. This can support over 1200 horsepower.

Greddy Twin Turbo Kit

Trust Greddy to design a properly engineered bolt-on twin turbo solution that fits the 2JZ like a glove. Their twin turbo manifold kit uses exclusive Greddy TD06SH-25G 10cm2 turbos to deliver potent low end punch and high rpm power.

With the twin HKS turbochargers and dialed-in turbo manifold design, Greddy's 2JZ TT kit puts down up to 1007 horsepower at 51 psi of boost pressure while retaining crisp street car drivability.

Turbonetics Godzilla Twins

The name fits the sheer power output that Turbonetics' Godzilla blow-through carb twin turbo setup can enable. They designed this turbo manifold specifically for extreme drag racing and turbocharged Supra applications pushing up to 1600+ horsepower.

These Godzilla twins feature billet compressor wheels capable of supporting over 100 lbs/min of airflow and matched to lightweight tapered roller bearing GT47 turbine housings.

Power Enterprise Twin Turbocharger Manifold

Japanese performance shop Power Enterprise produces their own twin turbo manifold designed around supporting their RX8 rotor twin turbocharger. This exotic turbo manifold assembly is CNC machined from high grade stainless steel.

Capable of over 1000 horsepower, their twin turbo manifold kit positions the turbos for optimized hood clearance while maintaining high velocity exhaust pulses. The divided outlet design equalizes flow and enables responsive spool with max rated power.

Wrapping Up

Twin turbocharging the legendary 2JZ inline-6 can enable extreme high horsepower builds exceeding four digit numbers. By designing or selecting a matched high flowing twin scroll manifold, you can take full advantage of running twin turbos.

Properly supporting your selected turbocharger combination with a custom or engineered twin scroll manifold is crucial to realizing your 2JZ's performance vision and goals.

FAQs

What are the benefits of a twin scroll manifold?

A twin scroll manifold keeps the exhaust pulses separate between each bank of cylinders. This improves spool, boost response, and max power capability compared to a single scroll design.

What size turbochargers work best for a high HP 2JZ?

For street cars making 800-1000HP, twin GTX3076R or GTX3582R turbos are common. For 1200HP+ drag cars, larger BorgWarner EFR 8374 or GTX47 turbos allow enough airflow.

How much fabrication is required to fit twin turbos?

Using a bolt-on kit like the Greddy twin turbo manifold only requires minor intercooler piping fabrication. Otherwise fabricating custom exhaust and oil/coolant line routing is required.

What metals should a twin turbo manifold be constructed from?

Using high grade stainless steel or Inconel is ideal to handle high exhaust gas temps and reliability at 1000+ horsepower power levels.

How much does a built 2JZ twin turbo kit cost?

All in you can expect to spend around $15-20k for quality twin turbos, manifold, supporting mods, tuning, and install labor to reach 800-1000HP.