In production from 1989-1998, the Nissan 240sx Coupe is perhaps one of the most modifiable vehicles in existence. Their versatility is touted in many racing circles, including drift and time attack communities. Because the S-Chassis has been around for over 30 years, the modding community has had ample time to produce a wide array of quality mods.
This guide will outline some of the best performance mods that can be done to a 240sx for under $1,000.
With the KA24DE found in all 240sx coupes rated for 135whp from the factory, additional power is often sought after. While the KA24DE would unquestionably benefit from forced induction, the price of a quality turbo kit might be prohibitive for some. For that reason, we’ll stay away from the topic of forced induction in this guide.
Even without turbo considerations, mod availability for 240sx coupes is quite extensive.
240sx Exhaust System
One of the most worthwhile mods for a naturally aspirated 240sx is a quality aftermarket exhaust system. The primary purpose of an aftermarket exhaust is to increase airflow over the restrictive stock system. A buildup of back pressure due to a restrictive system causes a net horsepower loss. By upgrading your S13’s exhaust a horsepower gain and improved gas mileage are a guarantee.
Let’s not forget about the sound either. Most aftermarket exhausts will get you the low, grumbly idle that many enthusiasts hunt for. With each system comes a different overall sound, so be sure to do some additional research to find the exhaust that sounds best to you.
HKS Nissan 240sx Coupe Hi-Power Exhaust System
Horsepower Gain: 5-15hp
Purchase Here: Enjukuracing.com
Our top choice for a quality 240sx Coupe exhaust system is the HKS Nissan 240sx Coupe Hi-Power Exhaust System. Keeping the factory catalytic converter intact, the HKS Kit provides a straight mid-pipe section and high-flow muffler.
Produced by HKS, quality is assured. HKS is one of the leading parts manufacturers in the JDM scene, with thousands of happy customers to vouch for their immaculate reputation.
As the HKS Hi-Power Exhaust is cat-back, you shouldn’t have any issues with emissions. Despite increasing airflow by a dramatic degree, everything remains street legal. No exhaust-related traffic stops in sight.
Most owners claim that the HKS Hi-Power system is one of the best sounding on the market; introducing a rich deep tone at idle and respectable growl in the higher revs. They also say that highway drone is a non-issue and that the decibel level is just right for a daily driver.
In totality, the HKS Hi-Power Exhaust System is a quality all-rounder. Whether you intend to keep your KA24DE powered 240sx Coupe naturally aspirated or have plans for big boost, the HKS kit is the way to go without breaking the bank.
240sx Brake Upgrade
One of the cornerstone mods for a better handling vehicle is an upgraded brake kit. This remains true for Nissan 240sx Coupes. Even with stock power, an upgraded brake kit will dramatically improve the performance characteristics of your 240sx.
In stock form, 240sx brake calipers stand at a meager, yet road appropriate, 252x20mm. While that is enough for most road-going applications, a larger set will increase performance for a number of reasons. Most prominently, larger brakes allow for better braking power under higher heat loads. This is essential if you plan on pushing your 240sx coupe to its limit.
A larger brake set will also disperse heat much better than stock brakes. This circumvents dreaded heat-soak, where excess heat and energy gets trapped in the brakes causing fade. A larger kit means less fade, allowing for uniform performance even under a heavy load.
240SX Coupe Z32 Big Brake Conversion Kit
Price: $395 per pair
Stopping Power Gain: 20-25% over stock
Purchase Here: 240sxmotoring.com
Comprehensive Install Guide: Speedacademy.com
Perhaps the most common 240sx brake upgrade, the Z32 brake conversion is the right move for anyone looking for more stopping power. Because the larger brakes come from another Nissan, the installation can be done entirely with OEM parts.
In terms of the performance that you should expect, most owners that have performed the swap say that the difference is dramatic, with the Z32 set providing around 20-25% more stopping power than the stock set. This should unquestionably be enough for aggressive backroad driving or track day outings.
In terms of the installation itself, there are a few considerations that must be made regarding equipment and other resulting effects. As the Z32 300zx has a 5-lug bolt pattern, the brake conversion will convert your 240SX to a 5-lug setup. Stock wheels will not fit over the bigger brakes, so larger wheels will also be required. The job is said to be somewhat extensive, but with proper equipment and a bit of automotive knowledge, it should be a bolt-off/bolt-on job.
This upgrade is one that will benefit a 240sx coupe regardless of power figures or additional mods. If brake fade is an issue with your stock brakes, this kit is a no-brainer. Additional stopping power is always a pro, both on and off the track. With a price of just under $800, a Z32 big brake swap is one of the most noticeable and performance-enhancing mods that you can do to a 240sx coupe.
240SX Coupe Coilover Suspension Upgrade
Staying consistent with the theme of performance-enhancing mods independent of power figures, coilover suspension is another way to change the handling characteristics of your 240sx coupe for relatively little cash.
It is a general consensus in the 240sx community that coilovers are the superior suspension option. Most 240sx owners advocate for skipping right to coilovers as opposed to an upgraded spring/shock combo. This is mainly due to the better value that coilovers provide. While a shock/spring combo would likely be cheaper, coilover performance is far superior for a slightly higher cost.
The prime benefit of coilover suspension boils down to adjustability. Compared to a traditional shock/spring setup, coilovers offer the advantages of adjustable ride height, dampening control, and even camber adjustment on most mid and high-price range options. The overall effect is dramatically improved grip around corners and a more planted chassis.
240sx Coupe Megan Racing Street Coilovers
Purchase Here: Enjukuracing.com
As an established suspension brand in the JDM community, Megan Racing is known for their above-class entry-level setups. As a street-style coilover, the Megan Racing kit is meant to be a healthy balance between comfort and performance-oriented.
With 8kg front and 6kg rear spring rates, these coilovers are stiff enough for most performance applications. This exact kit has been used on Team Enjuku Formula-D builds in the past. I’d say that is a solid testament to their performance. With 32 levels of damping adjustment, the Megan Racing kit can be dialed in to your exact preferences.
While performance is the ultimate goal with this set, most owners claim that they are a fantastic set for a daily driver as well. At softer damping settings, the set is said to feel firm and planted without busting teeth over potholes.
If you are looking for a quality, all-around set of coilovers, the Megan Racing kit is a solid option. Stock 240sx suspension often leaves much to be desired from a performance standpoint. With 30-year-old shocks and springs, wallowy amounts of body roll are to be expected in demanding conditions. The Megan Racing 240sx Street coilover set is guaranteed to solve this issue.
240sx Coupe Short-Throw Shifter Kit
While some vehicle mods are installed for performance gains, others boil down to feel. A short-shifter kit blends both of these elements. As with most pre-21st century manual vehicles, stock 240sx shifter travel feels like a country mile.
In addition to having a long throw, many of the factory shifter components are likely worn from 30 years of use and abuse. Luckily, there is one solution for both of these issues: a short-throw shifter kit.
The primary benefit of a short-throw kit is an improved shift feel, however, performance is affected too. With short-shift kits typically reducing throw by 30-50%, shift times are marginally decreased as well. This makes performance driving a bit easier, not having to fuss with your shifter for quite as long. Many 240sx owners also enjoy the notchier feel that the kits provide, turning a previously full-arm task into a simple wrist movement.
240sx ISR Performance Short Throw Shifter
Shift Throw Reduction: 50%
Purchase Here: Enjukuracing.com
As far as easy yet transformative 240sx mods go, it doesn’t get much better than this. Due to the fact that there are relatively few moving parts, the ISR Performance Shifter is easy to install. The solid aluminum construction also ensures long-term durability.
The ISR kit has one of the highest throw reductions on the market, reducing travel by 50%. That is a difference that would be immediately noticeable by anyone. Most customers say that the ISR kit compares favorably to almost everything else on the market. At only $112.50, no other kit will provide the same value for money.
Not only reducing shift travel, the ISR kit is also said to dramatically reduce any existing play while in gear or in neutral. As many 240SX shifters get sloppy from years of action, the ISR kit is a cheap and effective solution.
240sx Coupe Limited Slip Differential
When it comes to performance, how a vehicle puts its power down is just as important as the amount of power it puts down. For that reason, an upgraded differential is a transformative mod for a naturally aspirated 240sx. Nearly all 240sxs left the factory with an open differential, meaning that the rear wheels spin independently of one another. While practical for day-to-day use, there are better options if performance is preferred.
That’s where a limited-slip differential comes into play. In normal driving conditions, an LSD functions similarly to an open differential. The difference arises when traction is less in one drive wheel, typically the outside wheel in a demanding corner. In this instance, an LSD will add pressure to the side of the axle with less grip, preventing the wheels from rotating at significantly different rates.
This added torque helps the vehicle rotate more effectively through corners and reduces oversteer. Overall, this adds up to increased cornering speeds and overall stability. You’ll also be putting down maximum power without breaking traction. This is especially beneficial if you intend to track or race your 240sx.
240sx Coupe Tomei Technical Trax 1.5 or 2-Way Rear LSD
Purchase Here: Z1motorsports.com
As stated above, the effects of the Tomei Technical LSD will immediately improve off-the-line traction and cornering speeds. If you intend to use your 240sx for autocross or time trial applications, an LSD is a must.
Tomei is a leading parts manufacturer for JDM cars and is known for their Nissan performance parts. This is no exception. As one of the few plug-and-play LSD options for Nissan 240sxs, the Tomei Technical is likely the strongest and longest lasting.
Tomei offers both a 1.5 and 2-way LSD, each to suit two different purposes. The 1.5-way LSD performs best in an autocross or time attack setting. Functioning as stated above the 1.5-way locks the rear wheels under acceleration, allowing for more grip through corners. The 2-way LSD is best for drift applications. The 2-way locks the rear wheels under acceleration and deceleration, allowing for controlled slides with proper throttle control.
Regardless of your needs, an LSD will significantly improve both the handling characteristics and traction of your 240sx coupe. At under $1,000, the Tomei Technical LSD is the one to buy in terms of both longevity and versatility.
Top 5 240sx Mods Conclusion
The 240sx mod community is one of the largest and most varied aftermarket communities for any single vehicle. The 240sx is a proven vehicle for a wide array of motorsport applications, making mod choices difficult due to the sheer quantity.
While turbo kits are often high on the list when it comes to KA24DE power gains, there are still hundreds of fantastic performance-altering mods that make a 240sx even better to drive. With a $1,000 budget, any of the above mods are attainable and all will improve your 240sx driving experience dramatically.