When you think turbocharging, you probably picture a big snail bolted right next to the engine. But what if we told you that slapping the turbo at the rear of your car could be just as effective – and even come with some surprising benefits?
Let’s dive into how rear-mounted turbo systems work, especially when fitted to the 370Z, and why this is becoming a more popular choice for the likes of the 350/370z
What is a Rear-Mounted Turbo?
Instead of mounting the turbocharger up front near the exhaust manifolds, a rear-mounted turbo sits further down the exhaust path – usually where the stock muffler or resonator would be, towards the back of the car.
The exhaust gases travel a longer distance, spinning the turbine at the rear, and the compressed air is then routed all the way back up front to the engine’s intake.
The 370Z’s VQ37VHR engine is known for its high-revving, naturally aspirated power. But once you start craving more boost, you’ll quickly learn that space in the engine bay is tight. That’s where a rear-mount turbo shines:
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Exhaust Routing: The exhaust gases from the engine travel down the stock piping toward the back. Instead of ending at a muffler, they hit the turbo's turbine side. This means the only part of the exhaust you need to modify is the back box area. In this build we changed the flange from the oem flange to a t4 turbo flange.
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Turbo Placement: The turbo is mounted near the rear subframe or bumper area.
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Boost Piping: Compressed air travels forward through a front-mount intercooler and into the throttle body.
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Oil Management: A scavenge pump sends oil back to the engine, since gravity can’t help you out here like in front-mounted setups.
Why Rear-Mount on a 370Z?
The 370Z’s engine bay is notoriously tight, especially with the wide VQ37VHR V6. Traditional twin-turbo kits are effective, but:
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They require heavy fabrication,
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Engine-out installs (in many cases),
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Serious heat shielding, and
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Can cost thousands more in labour alone.
A rear-mount system bypasses most of those limitations by using factory exhaust routing and free space in the rear of the car. This makes it far more appealing for DIY customers or budget-conscious builds.
The Technical Details – System Components Breakdown
1. Turbocharger
A single rear-mounted turbo is typical – usually in the T4 or T3 frame size range. On this build we used a Maxpeedingrods GT45 t4 turbo.
2. Exhaust Piping
The system utilises your car’s stock or aftermarket exhaust pipes as the “hot side” feed. Exhaust energy may be slightly reduced by the time it reaches the turbo, which is why proper sizing and efficient routing is key to minimise lag.
3. Oil Supply & Return
This is critical. Since the turbo sits below the oil pan, a standard gravity-fed return won’t work. Instead, a scavenge pump is installed near the turbo to suck out used oil and return it to the engine’s crankcase or a catch can system.
A failure in this system can lead to turbo oil seal failure – so use a quality pump with a backup sensor. We also had a pump shut of delay wired in so after the car was switched off the pump would then stay on for 30 seconds after to drain any remaining oil.
4. Boost Piping
Cold-side piping runs from the rear of the car to the front – often 2.25" or 2.5" aluminium or stainless steel tubing – to a front-mount intercooler, then into the throttle body.
Despite the longer path, air temperature drops significantly, acting almost like a pre-intercooler before hitting the actual intercooler. This helps offset heat soak.
5. Tuning and ECU
You’ll need a proper ECU tune, preferably via EcuTek or UpRev, and a MAP sensor-based tune rather than MAF for easier airflow control. AFR sensors, boost solenoids, and widebands are also required for reliability and fine-tuning. We also added a fuel pressure sensor so our tuner could see any fuel pressure drops
6. Fuel system
You will need bigger injectors and upgraded in tank fuel pump. In this build we opted for 1000cc injectors and Walbro 450 fuel pump. If power goals are over 500whp we also suggest adding a fuel return system.
7. Clutch Upgrades
By adding a turbo you are increasing the stress on the OEM components. One of the first things to consider is changing the clutch. We always use competition clutches in all of our builds.
Pros of Rear-Mounting on the Z
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No Engine Bay Mods – No manifold swaps, no clearance issues, no melting wiring.
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Lower Under-Hood Temps – Keeps intake air and engine bay much cooler.
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Easier Maintenance – Less clutter in the engine bay; turbo is more accessible.
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Natural Cooling – Long charge pipes cool air before intercooling.
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Better Weight Distribution – Adds weight over the rear, improving handling balance.
Downsides to Watch Out For
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Turbo Lag – Longer exhaust travel means slightly slower spool-up, especially with larger turbos.
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Scavenge Pump Reliability – It’s a mission-critical component. Always carry a spare or monitor it closely.
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Road Debris & Weather – The turbo is exposed underneath the car, so proper shielding is essential.
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Custom Fabrication Required – Still not 100% bolt-on. You’ll need welding, fab work, and a good understanding of flow dynamics.
Rear-Mount on a Street or Track 370Z – Worth It?
If you’re looking to add boost to your Z without ripping apart the front end or dealing with extreme heat issues, a rear-mount turbo is a seriously viable option. It’s been proven on platforms like the C6 Corvette, and it translates well to the Z34 chassis with the right setup.
We’ve seen successful builds pushing 450–600whp with solid reliability and minimal engine bay drama. It's a clean, stealthy, and smart way to build power, especially if you want to retain drivability and save space up front.
