Nissan 240SX Clutch Upgrade: Choosing a Clutch for an SR20 or LS Swap
A 240SX rarely stays stock, and the clutch you need depends heavily on what is bolted to the front of the transmission. A tired KA24DE car with 200,000 miles needs a very different clutch than an SR20DET with a big turbo, and an LS swap changes the whole question. This guide explains how to choose, what the published torque numbers tell you, and the gotchas that trip up swap builds.
Shop the Clutch Kits for Your 240SX
These kits are in stock. Read each title closely, because the 240SX, Silvia and engine swap combinations are listed separately:
- Clutch Masters 89-98 240SX SRDET Engine and 240SX Transmission / 91-98 240SX 2.4L (From 7/90) (06054-HD00) - heavy-duty street kit for an SR20 with the 240SX gearbox, or a stock-engine 91-98 car.
- Clutch Masters 91-98 240SX 2.4L / 89-98 Silvia FX350 Clutch Kit (06054-HDFF) - the sprung fiber kit for tuned cars.
- Clutch Masters 89-98 240SX SRDET Engine and Transmission / 89-up Silvia SRDET (06144-HDTZ) - for cars with the SR20DET and its own transmission.
- Clutch Masters 89-98 Silvia 2.0L SR20DET FX400 Heavy Duty 8-Puck Sprung Ceramic Clutch Kit (06144-HDCL) - ceramic for higher power.
- ACT 1991 Nissan 240SX HD/Race Sprung 4 Pad Clutch Kit (NX4-HDG4) - a race-leaning kit.
Browse the full clutch kits collection and flywheels for the rest.
First Question: Which Transmission Do You Have?
Our Clutch Masters listings are split by engine and gearbox. Titles like "SRDET Eng. and 240SX Trans." and "SRDET Eng. and Trans." are different kits, because the clutch must match the bellhousing, input shaft and flywheel on the gearbox you are actually running. Before you order, identify your engine, which transmission is bolted to it, and the year of the car, then match that to the listing title. If the title does not describe your exact combination, ask before buying rather than guessing.
Signs the Clutch Needs Replacing
- Revs rise under load without matching acceleration, especially under boost.
- A burning smell after hard pulls.
- A pedal that engages high or chatters.
- Difficulty selecting gears with the engine running, which can point at a dragging disc or at hydraulics.
Choosing for an SR20DET
The published numbers help here. A Kamispeed listing for ACT's 1991-1994 240SX HD/Performance Street Sprung kit gives a 275 ft-lb capacity, 54% over OE, with light to moderate pedal effort and smooth positive engagement, an 8.8 inch (224 mm) disc and a 1 inch input shaft. A street kit like that suits a lightly modified SR20DET. For a car making real boost, step up to a sprung ceramic such as the Clutch Masters FX400, which the manufacturer describes as an extreme-duty street and race clutch with a sprung hub for some damping; it holds more but has a firmer pedal and more abrupt engagement than organic kits. Our FX350 kit (06054-HDFF) sits in between: Clutch Masters describes the FX350 line as 110% more holding capacity, aimed at tuned cars with a medium-boost turbo, with a slightly more aggressive engagement and some chatter.
Remember that an SR20DET swap can leave you with a mix of engine and gearbox parts, which is why the listing titles differ by gearbox. Confirm which combination you have before you order.
Choosing for an LS Swap
LS swaps bring more torque than any SR20, and the clutch decision depends on the transmission adapter you chose, not the 240SX. Two points from swap-kit sources are worth knowing:
- LOJ's 240SX FAQ says its billet aluminum flywheels will accept any 9.5 inch 300ZX non-turbo clutch or any 10 inch 350Z/G35 clutch kit, and that any Z32 transmission works with its adapter kits.
- Drifted's LS swap guide notes that with an LS and T56 transmission the factory clutch master cylinder is too weak to operate the internal slave of a larger, heavier pressure plate, so plan on upgrading hydraulics.
We do not list kits made specifically for LS-swapped 240SX transmission setups, so if you are on a 350Z-based adapter, the nearest match in our store is the 350Z clutch range (for example the Clutch Masters 350Z FX400 kit, 06047-HDCL), and our 350Z and 370Z clutch guide explains torque ratings in detail. Confirm with your swap kit maker that the kit and flywheel are compatible with your adapter before ordering. Do not assume a 350Z listing fits any swap because the source mentions 350Z clutches.
Replace While the Transmission Is Out
- Flywheel: resurface or replace it. See our guide on when to replace the flywheel during a clutch job.
- Release bearing and pilot bearing (in most kits where applicable).
- Rear main seal and transmission input seal.
- Clutch hydraulics: always on a swap, and especially with a larger pressure plate. See clutch hydraulics.
Cost and Effort
On a rear-drive 240SX the transmission comes out from underneath: plan a full day with a transmission jack. On a swap car, add time for adapter and hydraulics fit-up, and do the seals and flywheel in the same session.
Frequently Asked Questions
Is a stock-style clutch enough for an SR20DET?
Only for a mild setup. A published ACT street kit for the 240SX is rated at 275 ft-lb (54% over OE), so higher boost needs a stronger kit.
Will an LS swap need new clutch hydraulics?
Drifted's guide says the factory clutch master cylinder is too weak for the larger pressure plate used with an LS and T56 transmission, so plan for an upgrade.
Does the transmission matter when choosing a 240SX clutch?
Yes. Our listings are split by engine and transmission combination, so match the title to your setup.