The Nissan 350Z and the Quest for Forced Induction Power

The Nissan 350Z, with its VQ35DE or VQ35HR engine, has earned a solid reputation as a tuner-friendly platform that responds well to forced induction. Owners often look to superchargers as a way to boost horsepower without the lag associated with larger turbo setups. But not all superchargers are created equal, and the size of the unit plays a major role in determining how much power you can expect. This article breaks down the real-world power gains from 50mm, 60mm, and 65mm superchargers on a 350Z, along with the supporting modifications and tuning needed to get the most out of each option.

Understanding Supercharger Sizing and Types

Supercharger sizing in millimeters typically refers to the diameter of the compressor wheel or the inlet opening. A larger diameter allows more air to be moved per revolution, which translates to higher boost potential and greater power. However, bigger isn't always better for every build. The 350Z can be fitted with centrifugal superchargers (like those from Vortech or Stillen) or positive-displacement units (such as twin-screw or roots-style). The sizing in mm is most commonly associated with centrifugal superchargers, where the impeller diameter determines airflow capacity.

For the VQ35 engine family, common supercharger sizes are:

  • 50mm – entry-level, low boost, minimal modifications required
  • 60mm – moderate boost, common for street builds
  • 65mm – aggressive, high boost, requires extensive supporting upgrades

It's important to note that the actual power output depends on the supercharger's internal design, drive ratio, and the boost level you run. The mm measurement is a guideline, not an absolute guarantee of power.

Power Gains from the 50mm Supercharger on a 350Z

A 50mm supercharger is typically found in budget-oriented kits and on street cars that prioritize daily drivability over peak horsepower. On a stock VQ35DE or VQ35HR, a 50mm unit running around 6–7 psi of boost can add approximately 50 to 70 horsepower at the wheels. That brings a stock 287–306 hp engine up to around 340–370 whp, depending on the specific dyno and correction factors.

Advantages of the 50mm Supercharger

  • Lower cost – both the kit itself and the supporting mods are minimal
  • Simpler installation – often uses the stock fuel system and exhaust
  • Reliable daily driving – low heat generation and minimal stress on the engine
  • Retains OEM-like drivability – no massive power spikes, easy to control

Disadvantages

  • Limited power ceiling – you're unlikely to exceed 400 whp without changing the pulley and risking overspeed
  • Less headroom – future upgrades are more expensive if you later decide to go bigger
  • May still need a tune – even with a conservative kit, a proper ECU reflash or piggyback is recommended

Real-World Example

Many 350Z owners have installed the Stillen Supercharger Kit (which uses a 50mm impeller in some iterations) and reported gains in the 55–65 whp range on bone-stock engines. With an aftermarket exhaust and a good tune, those numbers climb to 70–75 whp. The engine remains reliable for tens of thousands of miles provided maintenance is kept up.

Power Gains from the 60mm Supercharger

The 60mm supercharger is the sweet spot for many 350Z enthusiasts. It offers a substantial jump in power without requiring a complete engine rebuild. With boost levels around 8–10 psi, a 60mm unit typically adds 70 to 100 horsepower at the wheels, bringing total output to 370–410 whp. Some aggressive tunes with race gas or ethanol can push closer to 420 whp.

  • Balanced performance – enough power to be seriously fast, but still manageable on stock internals
  • Better torque curve – the larger impeller flows more air across the rev range
  • Moderate cost increase – the supercharger itself is more expensive than a 50mm, but supporting mods are similar
  • Works with standard fuel systems – upgraded injectors (440–550cc) and a fuel pump are recommended but not always mandatory at lower boost

Supporting Mods for the 60mm

To safely run a 60mm supercharger at 9–10 psi, you should include these upgrades:

  • High-flow fuel injectors (at least 550cc)
  • Upgraded fuel pump (e.g., Walbro 255 lph or AEM 320 lph)
  • Aftermarket exhaust system (cat-back or test pipes)
  • Cold air intake (usually included in the kit)
  • ECU tuning via UpRev, EcuTek, or a standalone
  • Optional: oil cooler, larger radiator

Real-World Example

Vortech's V-3 Si trim supercharger (often spec'd with a 60mm impeller) is a common choice for the 350Z. Owners on forums like my350z.com report dyno sheets showing 390 whp on pump gas with a conservative tune. Adding a water-methanol injection kit can push that to 430 whp safely.

Power Gains from the 65mm Supercharger

The 65mm supercharger is the largest bolt-on impeller size commonly used on the VQ35. It moves a massive amount of air, allowing boost levels of 12–15 psi or more. On a built engine with forged internals, a 65mm unit can add 100 to 130 horsepower (or more) at the wheels, pushing output to 430–470 whp. Some setups with aggressive tuning and E85 fuel exceed 500 whp, but that requires extensive supporting work.

What You Need to Run a 65mm Supercharger

Running a 65mm supercharger on a 350Z is not for the faint of heart. The stock VQ35DE bottom end is reliable up to about 450 whp, but the ring gaps and rods are marginal for sustained high boost. Most owners choose to build the engine with forged pistons and rods before attempting 15+ psi. Essential modifications include:

  • Built short block (forged pistons, rods, and bearings)
  • Head studs (ARP or similar)
  • Larger fuel system (750–1000cc injectors, dual fuel pumps, return-style fuel system)
  • Heavy-duty intercooler or charge air cooler
  • High-flow exhaust (3-inch or larger)
  • Standalone ECU (Haltech, Motec, or AEM Infinity)
  • Upgraded cooling system (oil cooler, larger radiator, heat exchanger)
  • Stronger clutch/flywheel

Pros and Cons of the 65mm

Advantages:

  • Maximum power potential for drag racing or track use
  • Impressive torque curve – the engine pulls hard to redline
  • Can be tuned for E85 for even more output

Disadvantages:

  • Very high cost (kit plus build plus tuning can exceed $15,000)
  • Reduced reliability if engine isn't properly built
  • Increased heat and parasitic loss
  • May not be street-friendly for daily use

Real-World Example

Stillen offers a "Stage 2" supercharger kit that uses a 65mm impeller in its later revisions. On a built VQ35HR, many owners have reported 470–490 whp on 93 octane. With a methanol injection kit and a conservative tune, some have pushed past 520 whp on the dyno. Track reliability is mixed, but those with proper cooling and oil management have had good results.

Factors That Influence Actual Power Gains

No matter which supercharger size you choose, the final power output depends on several variables. Understanding these will help you set realistic expectations:

Engine Condition and Compression

A healthy VQ35 with good compression will make more power and tolerate boost better than a worn engine. Low compression in one or more cylinders can cause knock and limit your tune. Always perform a compression test and leak-down test before installing forced induction.

Fuel Quality

Higher octane fuel allows more timing advance and higher boost. Most 350Z supercharger kits are designed for 91–93 octane pump gas. Running E85 can provide a significant safety margin and power increase because of its high octane rating and cooling effect, but requires a much larger fuel system.

Tuning

Proper tuning is the single most critical factor. A poorly tuned 50mm supercharger can be less reliable and less powerful than a well-tuned 65mm. For the 350Z, options include UpRev (OEM flash), EcuTek (for HR engines), and standalone ECUs. A good tuner will dial in fuel, ignition timing, and boost control to match your mods and fuel.

Supporting Modifications

A supercharger is only one piece of the puzzle. To realize the full potential of a 60mm or 65mm unit, you need:

  • Free-flowing intake and exhaust
  • Intercooler or charge air cooler (mandatory for 60mm and up)
  • Upgraded fuel delivery
  • Proper heat management (oil cooler, larger radiator)
  • Strong drivetrain (clutch, differential bushings, axles)

Altitude and Ambient Temperature

At higher altitudes, the air is thinner, and a supercharger will produce less boost. Conversely, hot summer air reduces air density and can lead to detonation if not accounted for in the tune. A good intercooler and a tune that adjusts for IAT are essential.

Comparing the Three Sizes: Which Is Right for You?

Here's a quick comparison to help decide based on your goals:

  • 50mm – Best for a mild street build on a budget. You get a noticeable power increase without major supporting mods. Ideal if you want a fun daily driver that remains reliable.
  • 60mm – The all-around performer. Offers a serious power bump and still works with stock internals up to around 420 whp. Requires a few supporting mods but is the most popular choice.
  • 65mm – For power junkies and track enthusiasts. Requires a built engine and extensive upgrades. Not recommended for beginners or daily drivers unless you have deep pockets and a high tolerance for maintenance.

Frequently Asked Questions

Can I install a 65mm supercharger on a stock engine?
It's not advisable. The stock VQ35DE pistons and rods are not designed for the cylinder pressures generated by 12+ psi. You risk ring land failure or rod bending. At minimum, you'd need forged pistons and rods, plus head studs.

Do I need a built transmission for a 60mm supercharger?
The stock CD009 transmission is strong and can handle 400–450 whp without issues if driven reasonably. However, aggressive launching and drag racing can break gears or syncros. Consider a clutch upgrade and a stout differential.

How long will a supercharged 350Z last?
With proper tuning, supporting mods, and maintenance, a 50mm or 60mm supercharged car can last 50,000–100,000 miles. A 65mm built engine can also be reliable if built correctly, but it demands more frequent oil changes and checks.

Where can I find more information on supercharging the 350Z?
Check out dedicated forums like 350Z Tech and The370Z.com (covers both Z33 and Z34). Many kit manufacturers also provide detailed installation guides and dyno sheets.

Conclusion

Choosing a 50mm, 60mm, or 65mm supercharger for your 350Z comes down to your horsepower goals, budget, and willingness to upgrade supporting components. A 50mm unit offers 50–70 wheel horsepower in a reliable, budget-friendly package. The 60mm delivers 70–100 whp with moderate upgrades and remains streetable. The 65mm pushes 100–130+ whp but demands a built engine and extensive supporting mods.

Before you buy, have a clear plan for tuning, cooling, and fuel delivery. No matter which size you pick, a properly installed and tuned supercharger will transform your 350Z into a much more exciting car. Take the time to research kits, talk to current owners, and invest in a professional tune. That's the secret to getting the most from your forced induction build.