While the 350Z provides pretty impressive performance from the factory, very few owners keep them in stock form. That’s likely because there are too many tempting performance-enhancing parts out there for them these days. In the 20 years since the 350Z’s release, it has become a favorite in multiple enthusiast communities and has huge aftermarket support.
You can make a lot of power on the VQ35 engine, but it requires turbocharging which makes a build expensive pretty quickly. In this guide we’re going to cover everything before getting into a serious forced induction build: suspension upgrades, tuning, intakes, and exhausts. If you want to jump into the world of forced induction, we have a complete turbo guide that can teach you how to build a 400-500whp+ 350Z.
Nissan 350Z Performance Upgrades
- Sway Bars
- Plenum Spacer
1) Coilover Upgrade
One of the best handling-improving modifications that you can do to a 350Z, and most cars for that matter, is a set of good coilovers. One of the main gripes with the stock chassis is its relatively soft suspension and high ride height. While that makes it a good daily driver, it detracts from its performance potential.
The topic of coilovers is a nuanced one, as they come in all different shapes and sizes. With that being said, they all serve the same general purpose. In general, coilovers increase suspension stiffness over a stock setup which simultaneously allows a car to run lower to the ground. This results in your 350Z, in this case, cornering better by having better contact with the road and by having a lower center of gravity. Coilovers offer adjustable ride height, meaning that you can raise and lower your car by rotating an adjustment collar on the strut assembly.
Some higher-tier 350Z coilovers offer additional features like adjustable damping, which adds another element of customization depending on your application. Damping is good for a daily driver that doubles as a track day car, as it allows you to adjust ride stiffness on the fly. There’s typically a knob that you turn either clockwise or counter-clockwise to soften or stiffen the ride. For daily driving, you can set the coils to a soft setting to handle road imperfections better or set them to a stiffer and more planted setting when you get to the track.
Coilovers vs Lowering Springs
In my opinion, there shouldn’t even be a debate because there’s truly only one correct answer. While lowering springs might provide a solution to the dreaded 350Z wheel gap, they won’t provide the same performance that you’d see from a sturdy set of coils.
Unlike coilovers, lowering springs are not height adjustable and use you car’s stock struts instead of replacing the entire suspension assembly. In order to provide a lower ride height, lowering springs are typically shorter springs with a slightly higher spring rate over the stock 350Z setup. With that being said, they lack almost all of the customizability that you’ll find with a set of coilovers. However, due to the fact that you are only replacing the springs, they come at a significantly lower cost.
- Flatter cornering resulting in better handling
- Ride height adjustability / 1-5” drop
- Damping adjustment on higher-end setups
- Better on and off-track performance
2) Upgraded Sway Bars
While upgraded suspension will improve the handling characteristics of a stock 350Z, coilovers aren’t the end-all-be-all to all of the Z33’s handling issues. Upgraded sway bars are another great handling improving mod, especially when paired with upgraded suspension.
Upgraded sway bars have the potential to improve overall chassis stiffness, reduce weight, and add an additional level of adjustability to your Z33 build. The purpose of a sway bar is to link the left and right sides of a vehicle’s suspension, in turn resisting the torsion applied to the chassis when cornering. Upgraded sway bars tend to resist torsion better than stock ones, decreasing body roll.
In addition to providing better torsional stiffness, upgraded 350Z sway bars tend to be lighter than stock ones. Decreasing weight is always a plus on a performance car. Most aftermarket options also provide a high degree of stiffness adjustability, making it easy to set up your Z exactly how you want it.
3) Upgraded Exhaust
An upgraded exhaust is another 350Z modification that requires some thought. There are three main considerations to take into account: price, sound, and performance.
Cat-back exhausts are without question the most common type of exhaust fitted to lightly modified Zs. Cat-back exhausts are exactly what they sound like. They replace all of the factory exhaust components from the catalytic converter to the exhaust tip. This type of exhaust is generally made of stainless steel and is made to improve exhaust gas flow out of the engine, resulting in a bit more power and a lot more noise.
Aftermarket cat-back systems can vary a good amount in terms of their pipe diameter, tip diameter, and how they exit the vehicle. Some aftermarket 350Z exhausts are single-exit, but the vast majority are dual-exit like the stock exhaust. The sound produced by an aftermarket exhaust is heavily dependent on the diameter of the exhaust piping and the type of muffler that it employs.
- Better exhaust flow resulting in more power/torque
- 10-20 horsepower / 10-25 lb-ft of torque gain
- Better exhaust tone
- Imrpoved exhaust aesthetics
4) Cold Air Intake
A performance intake is an excellent option for those looking for a relatively inexpensive Z33 Nissan 350Z performance modification. Depending on how you look at it, a performance intake can be considered a great starting point or the finishing touch to a highly tuned build. The purpose of an upgraded performance intake is to increase engine breathability over the stock setup. In general, the performance of an upgraded intake scales with engine performance, as highly modified engines can often be throttled by poor airflow.
If you are on a budget, we recommend retaining the stock airbox but equipping it with a K&N drop-in filter. This increases the filter surface area and allows for better breathability.
In general, horsepower and torque gains from a 350Z cold air intake are marginal. However, they are a good option for those looking for a relatively inexpensive mod that will bump performance slightly. In most cases, you can find a good intake for a couple of hundred dollars. They are usually very easy to install. The biggest power gains from an intake are achieved when forced induction is added, but taking that out of the picture you can expect power gains in the 3-6whp range and torque gains around 2-4wtq.
- 3-6whp gains
- 2-4wtq gains
- Increased airflow
- Cool intake engine noise
- Quicker throttle response
5) Plenum Spacer
This mod is a unique one to Nissan 350Zs and Infiniti G35s with the VQ35DE engine. The VQ35DE engine has an awful plenum design which cuts off airflow. The intake plenum is the part of the intake manifold that holds all of the air and distributes it to the cylinders. It has “runners” that branch off of it to feed each cylinder with air. On the VQ35DE the spacing between the plenum and the first two runners is so small that it restricts airflow and reduces power.
A plenum spacer sits between the upper and lower parts of the plenum and increases the air capacity of the plenum. Doing so increases the airflow to the cylinders, providing more power.
Plenum Spacer Benefits
- ~8whp bone stock
- Up to 15whp with intake, headers, exhaust
- ~12wtq gains
- Improved airflow
- Lower air intake temps
The Nissan 350Z is unquestionably a great platform right from the factory. It has all of the characteristics of a great sports car. While the Z33 is competent in stock form, it can be made significantly better with the right performance modifications.
In this article, we covered both handling-improving modifications and power-increasing modifications. Since the 350Z is known for having a less-than-ideal suspension setup from the factory, coilovers and upgraded sway bars can improve your Z significantly when it comes to cornering. With a coilover/swaybar combo, your 350Z will be able to corner flatter and have better contact with the road.
It is pretty hard to squeeze a sizable amount of additional power from a stock VQ35DE without forced induction. However, there are quite a few worthwhile upgrades that you can do that won’t break the bank like a turbo. An upgraded intake, exhaust, and plenum spacer will net somewhere around 30-40 additional ponies out of your Z. While that might not seem that significant, it’s a difference that you’ll be able to feel. Those three mods combined will only cost a fraction of what a turbo or supercharger kit would as well.