The Nissan 240SX is one of the OG drift platforms, with only the Toyota AE86 “Hachi Roku” Corolla held in higher acclaim. As a result, much like the Corolla, stock virgin examples and even well-kept low-mileage tuned cars are becoming hard to find. In many cases those wanting a quality starting point may have to settle for a car equipped with an automatic transmission.
The 240SX breaks down into two model designations. The S13 vintage spans from 1989 to 1994, and the S14 models track from 1995 to 1999, but a distinct freshening in 1997 serves to split the S14 model run in two.
Left: Single-cam KA24E. Right: Twin-cam KA24DE.
In model years 1989 to 1990, the S13 240SX was powered by a KA24E single-cam four banger with three valves per cylinder. This early engine is rated at 140 horsepower and 160 pound-feet of torque. These cars were known as pignose or ‘Zenki’ (Japanese for early edition) in Nissan talk.
For 1991, the 240SX received a smoother, more wedgy nose and was updated with the double-overhead cam KA24DE that pushed output to 155 horsepower and 160 pound-feet of torque. The 1991 to 1994 model S13’s are known as ‘Chuki’ (middle version). In Japan the production of the S13 continued, so these JDM-only models get the ‘Kouki’ (late version) moniker.
The S14 hit the streets in 1994 but was billed as a 1995 model. This is where lug count comes into play, as base models were four lug and up-level trim 240SXs featured five-lug wheels. The early S14s from ’95 to ’96 are known as ‘Zenkis’ while the end of the run from ’97 on are known as ‘Koukis’.
Basic Performance Upgrades (BPU) 160 Wheel Horsepower
Too many people want to jump right into engine swaps, turbo upgrades, and power mods when the rest of the car is falling apart. – Hok Cheng, J-Tune Performance
There is a tendency, perhaps understandably, to think of basic mods in terms of power, but that should not always be the case. We asked 240SX aficionado and owner of Wilmington, Delaware’s J-Tune Performance Hok Cheng where to start your 240SX tuning odyssey.
“In my opinion,” quipped Hok, “the first three mods for new 240SX owners should be replacing or upgrading suspension components, brake upgrades and/or maintenance, and taking care of the rusted spots in the body. These S-chassis cars have developed a few known areas that are susceptible to rust like the front strut tower, frame rails, and trunk. Too many people want to jump right into engine swaps, turbo upgrades, and power mods when the rest of the car is falling apart. These are old cars; many are 26 or 27 years old and have been abused in their life so prepare their foundation for the power you hope to throw at them later.”
Twin-cam KA24DE with typical bolt-on modifications.
In fact, when it comes to the 240SX platform, throwing a cold air intake and a set of headers at the KA can be a waste of time and money if you plan to take things further in the future. These particular basic bolt-ons become null and void when the 240SX enthusiast eventually looks to go turbo or swap engines. So only a big-bore exhaust makes sense as it will survive either scenario.
The major point of contention in the 240 world is whether to turbocharge the existing KA, resulting in the famed KA-T, or go the engine swap route, with the most popular swap being the SR20DET. As one would expect, there are two distinct and committed camps when it comes to boosting the S-chassis 240SX, based around these two engines
Advanced Performance Upgrades – KA-T 220 WHP-350 WHP
The most moving argument for supporters of the KA-T is the cost of the SR swap versus its true power potential. Remember, going with an SR represents a 20-percent loss of displacement. Further, popular SRs are rated at 205 horsepower, which translates to around 175 at the wheels – not really a stellar starting point. Entry fees can be $2,500 to $3,000 depending on what ancillary components come with the engine-swap candidate and there are numerous installation and tuning challenges ahead. Complete SR swaps can reach up to $6,000 once all the costs are factored in, and then there is the vehicle downtime to consider.
Turbocharged single-cam KA24E.
The SR is a lighter package, so if you’re looking to handle that may be an advantage. – Clark Steppler, JWT
“It’s an interesting debate,” says Clark Steppler of Jim Wolf Technology
(JWT). El Cajon, California-based JWT has been at the forefront of Nissan performance since the cars ran carbs and were called Datsuns. “Of course there’s the initial cost right off the bat. The SR is a smaller displacement engine so you’re throwing away 400cc of displacement in the trade off. The SR is a lighter package, so if you’re looking to handle that may be an advantage. To me the KA-DE is the bigger brother; it’s the big-block Nissan four-cylinder. It has a real robust iron block, has a bigger bore, a big, taller deck height… more big parts to it, and therefore, more power potential.”
“The SR is the smaller, lighter aluminum option. I will say it has been easier to develop cams for the SR because it has the finger follower rocker arm setup so it’s easier to drop a big-duration, big-lift cam and go for the boost. So we tried to match that with the KA-DE engine. Get something that could compete on that level on the valvetrain side to get comparative duration and lift and generate the flow potential out of the KA engine that is in-line with the SR.”
Turbocharged twin-cam KA24DE.
JWT has developed two cam profiles for the KA, a spring-and-retainer kit, and numerous modified ECUs designed to run all-motor set-ups as well as turbocharged KA-Ts with standard MAF and 50-pound injectors, as well as bigger custom MAFs and bigger injectors.
Budding boost fiends that choose to stay with the KA can choose from a number of turbo kits, from a bare basic 7 PSI set-up that will deliver approximately 220 wheel horsepower to a more advanced system that really wakes up the KA24DE. It should be noted that the twin cam DE is the best way to go KA-T, but most kits physically fit either configuration.
Cincinnati, Ohio’s Import AutoPerformance has a staged turbo kit program for the 240SX. Its Stage 1 is a bare basics kit designed to work off wastegate pressure of 7 PSI. All Import AutoPerformance kits are anchored with an AP T3/T4 hybrid turbocharger. The Stage 1 setup has an optional fuel pump and uses a boost sensitive Fuel Management Unit to provide fuel enrichment. This kit is best used by owners with an existing fuel/tuning strategy. The Import AutoPerformance Stage 1+ adds a Jim Wolf Technology ECU, a MAF, larger injectors, and an electronic boost controller to the mix. Max boost pressure checks in at 15 PSI and the base kit costs $2,999.
Import AutoPerformance’s Stage 2 kit adds fortified internals to the equation. It includes a set of forged Ross Pistons, forged Pauter rods, ARP head studs, a GReddy Profec B Series II electronic boost controller, and a more aggressively tuned Jim Wolf Technology ECU. With the built bottom end, the KA-T is able to withstand the rigors of ingesting more boost and producing more power. In this trim, the engine should belt out a very respectable 350+ wheel horsepower. The top-of-the-line Import AutoPerformance kit costs $6,499. Of course, Import AutoPerformance has a number of optional offerings for those who want to push the boundaries of the KA-T.
Going For The Gusto: Engine Swapping
The truth of the matter is the SR versus KA-T controversy is a bit long in the tooth. It’s outdated because today’s enthusiasts are swapping Nissan RBs and Chevrolet LS small-block V8s into the nimble S-chassis 240SX at a furious rate.
Corvette LS small-block V8 swap.
RB and LS engines are significantly more powerful options out of the box and have far greater tuning potential than the SR. J-Tune’s Hok adds the Toyota Supra 2JZ-GTE to the list and has something to say about each approach.
“One of the draws of the SR20DET swap is simplicity because the 240SX JDM counterpart, the Silvia, comes with this engine in Japan so it drops right in. For the RB, the attraction is the JDM angle, of course more cylinders and more power potential, and people will always chase the Skyline dream. The Chevy LS engines are found mostly in the drift scene. They make good low-end torque, and it’s fairly easy and cheap to make 450-plus wheel horsepower with a small-block V8. As for the 2JZ, I don’t know why people like to go that route. Maybe they want to be different?”
Nissan RB25 swap.
Steppler says he has seen RB conversions go up in popularity. “The RB swap keeps the motivation in the Nissan family,” says Steppler. “Some guys are trying to use the stock GT-R crossmember to pull off the swap, but there are kits that help the process. McKinney Motorsports and Sikky make tons of good swap stuff, well thought-out, well executed. In many ways the RB25 is the way to go as its rear-drive configuration is a better fit in the 240SX.”
“At JWT we do a deal where we use an ECU from a ’92 to ’94 Maxima, a Maxima twin-cam, and it runs the single-turbo RB25s really well. They are a great under-$100 computer core and the head console connection is usually something we can modify to make it plug in. We have been selling a bunch of these and it’s never for a Skyline – it’s almost always for a 240.”
The LS option pisses the purists off to no end, and there is a certain glee to be had by doing so. This swap has a lot going for it. The engines are cheap, very accessible, easy to boost, and there are plenty of well-sorted-out kits for the install that address mounts, wiring, and the driveline. There’s a lot to like.
What’s Trending: The Future Of The 240SX
“The trend seems to be solidly entrenched in drift car building… it is not a new trend but it is still going strong,” relates Import AutoPerformance’s Hok. “I don’t know what the next hot things are for the 240SX, but as a S14 owner myself I would like to see 240SX owners respecting the S-chassis more, and because you pay $500 to $4,500 for a 240SX doesn’t mean you just install some cheap knock-off parts and have your buddy do the engine swap for $200 and say the car runs like crap because ‘it just needs a tune,’ and put on a set of $125 race look-a-like wheels then go drift and think you’re a pro… Sorry I didn’t mean to go off like this!”
Whoa, slow your roll Hok. Catch your breath…
“To sum it all up,” says Hok, “I think the platform, front-engine, rear-wheel-drive is outstanding, there are literally millions of parts out for it but I see accessibility being a problem as it’s getting harder and harder to find a 240SX that’s clean and ready to mod.”
Nissan SR20VE engine.
Steppler sees a renaissance for the SR swap, citing the allure of the JDM scene, but not a DET swap. “Then there’s the whole SR20VE thing,” quips Steppler. “The SR20VE is a front-drive engine or transverse-mounted engine but there’s a lot of guys building a Frankenstein engine, dropping the variable valve VE head on a rear-drive block and sliding it into a 240SX. That’s probably the latest frontier in the 240 scene. The VE design cylinder heads have the same reputation as VTEC in the Honda world. Three cam lobes for each cylinder on each side, two primary ones for low-speed mode and one center one where the rocker arm clicks into position hydraulically for high-speed mode. There is loads of potential in this approach. The SR20VE heads flow more than any standard SR20DE head and while we haven’t developed any cams for the VE, we are working in that direction.”
The 240SX certainly has the JDM mojo so it looks to be a modification platform for the ages. The key for enthusiasts jumping into the game is determining where you stand on the swap-versus-KA-T dispute before making your move.
Your answers to the swap question, the intended direction of your build, and the depth of your wallet will play an important role in determining what kind of 240 will make the best starting point. If you’re swapping, engine condition and to a certain degree the year of the vehicle in question are less important. If you are looking to go KA-T you want a DE-era car with an engine that is up to the challenge. As in many endeavors, the devil is in the details and the payoff is at the end of the road. The S-chassis can lay down a long road, so contemplate deeply.