Ken's 240SX: Twenty Years in the Making

A student of motorcycles, Ken Yu spent his formative years tracking two-wheeled vehicles at Thunderhill, Laguna, and Sonoma. Eventually, he grew tired of taking spills and started looking for a four-wheeled way to get his fix. Specifically, he wanted something easily modified and cost-effective. Back in 2001, 240SXs could be found for nearly nothing — especially ones with blown motors.

A Zilvia.net posting led him to this 1989 hatch, which had been sitting for some time and needed a little love. Well, a lot of love. Aside from the blown motor, there were some serious issues contributing to the low cost of the car. “Someone left a burger in the back. There were maggots everywhere!” Still, $1,500 was a steal.

He started with a basic set of suspension upgrades. Whiteline sway bars, Megan Racing track coilovers, SPL lower arms and tension rods.

Out came the interior and in went the vinegar solutions. Then came a stock SR20, Z32 brakes, Tokico shocks, 5Zigen wheels, and Federal tires for plenty of fun in those halcyon post-college years. And this first round of modifications didn’t break the bank; many youngsters could swing these back then — no pun intended. When a full S13 front clip only cost $2,500, it was not too hard to put a quick 240SX together.

Rather than take the typical drifting route, he decided to make his 240SX corner. At 2,600 pounds with ~200 to the tires, the 240SX could graze 100 at the end of Thunderhill East’s front straight. It was nimble enough to get around many autocross courses, too.

By transplanting the motor without replacing the coolant hoses, Ken blew a pinhole leak in a coolant line at Thunderhill in the middle of July. Three of the ringlands broke, sending shrapnel into the head. He managed to limp the car all the way home to Hayward with regular coolant top-ups, but the SR was toast. He rolled it into the back of his garage with hopes to quickly replace the motor, but he didn’t bet on the next chapter of life taking him down a very different path than he’d pictured.

Ken got married, had two kids, a dog, and bought a house, so the track toy no longer took precedence. However, he kept the dream alive over the next five years by amassing a small stockpile of go-fast parts and tools.

Starting seven years ago, from ten to midnight — after the kids had gone to sleep, Ken would sift through his parts pile and make small steps towards rebuilding the car. Megan Racing coilovers with Swift springs, a pair of Sparco seats, an extensive cooling package, and a bolt-in cage set the tone: it was going to become a full-on track car built on years of forum trawling.

With his new CD009 on the floor, Ken spent a couple nights fitting Jun Flares and GarageMak overfenders.

Lots of research was needed to find out all the desired suspension settings for the 240SX — no darling of the track day community. With relatively scant information available for track-oriented S-chassis, he had to consult some of the video library he’d amassed over the years. “I’ve been watching Video Option since Volume 12.”

As this would be a fat-tired track car with a need to put power down better than what a stock S13 ever could, he had to identify the flaws of the suspension setup.

Up front, he added a set of Geomaster knuckles to lower the roll center for improved camber and toe curves. Along with that, he threw on most of the S13 parts in the SPL catalog, Techno Toy Tuning’s lower front arms, and even an S14 rear subframe for slightly better geometry and a wider track. Thankfully, retrofitting the older car with this S14 part only required a set of conversion bushings.

It would have to stop well, too. There were the two-piston rear Brembos sourced from a 2004 Subaru STI and mated to two-piece Girodisc rotors with Carbotech XP12s. Installing them was a cinch, too — almost a bolt-on affair.

At the front, the Core4 Motorsports Wilwood six-piston with Carbotech XP16s fulfilled the same need for easy modification, while offering far more reassurance than any hodgepodge of other car’s parts. Any track rat loves knowing that the kit on their car has been used by Core4 on their Silvia build for AER endurance races.

“Collecting all those parts was what kept the dream alive.”

When the ball was officially running, he called on two respected old school shops to help him rebuild the one piece he didn’t replace himself. Lonnie Jenson Co increased the SR’s bore to 86.5 mm and assembled the bottom end with Eagle rods and CP pistons. Performance Options rebuilt the head, while Ken added HKS Step 3 camshafts and dual shim rocker guides to keep the head from vibrating itself to bits at higher revs.

With a whole new fuel system and a Link G4X standalone ECU to decide on the right blend, Ken knew that he’d be stretching the stock gearbox to its limit. A Mazworx conversion kit, a CD009, and an ORC twin-clutch disk made up the the beefy new drivetrain — more than strong enough to handle 360 horsepower at 310 lb-ft at 5,500 rpm. That was sent back to an S15 helical differential with a 4.3 final drive. The combination of this gearbox and rear end resulted in explosive acceleration.

Getting tuned at Blacktrax.

After bolting in and tuning the new powertrain, the car would hook when pointed directly ahead, but the lack of compliance over surface variations caused Ken a few spins. At first, Ken struggled to find much grip coming through Turn 3 and 3A at Sonoma. “The inside wheels kept losing contact due to the lack of droop and suspension compliance. The solution was to ensure 30% of the suspension travel was reserved for droop through the helper springs,” Ken noted.

With more toe-in at the rear and a TCS Sportline rear wing, the car’s stability improved at higher speeds and under heavy braking. Being heavier in the front than the rear, it still gets a little light over the crest of Laguna’s Turn 1, but it’s less than vicious. The wingless iteration felt like it might bite his head off.

To expect much more from the projet would be unfair. December 30th was the first time he had this car on track in over a decade. And, wisely, Ken wanted to study the ways to get a dependable car out on track first.

Clearly, Ken’s done his homework. The engine manages temperatures well for a turbo car — admittedly, only cold-weather testing has been done so far, but it’s likely cooling won’t be a problem except perhaps on the warmest days.

The geometry is improved, the drivetrain handles the horsepower well, and the maintenance it requires is relatively low for an old Nissan. There’s also little tweaks that show an attention to detail and an emphasis on presentation, like how the ISR exhaust extends far enough to avoid blackening the bumper. It’s pretty — and that’s not always a great descriptor for a 240SX with bolt-on over fenders.

The attention to detail and insistence on putting reliability first will make the car’s issues easier to diagnose. However, half the car’s ancillaries are OEM SR20, so time will tell how well they’ve weathered the elements.

It’s clear Ken’s laid the right sort of foundation. Coilover testing, adding a front splitter, and increasing body rigidity are the main items on the agenda. Seam welding around the hatch and the doors — two massive apertures for such a small body — should make another massive step forward in making this middleweight handle well. Buttoning it up will take time, but Ken’s already sunk two decades into this car and his enthusiasm for tuning the 240SX hasn’t diminished one iota since the start. In the grand scheme of things, what’s another year?

Adam's S13 Coupe: Silvias Do More Than Slide

Some might think that S13 coupes aren’t really suited to turning quick laps, but some know better. Adam Swan’s owned thirty-five different S-chassis cars, so he knows better than most. This particular car, bought before some of the JDM favorites were considered investments, only set him back a few grand. That would be a steal for a stock car nowadays, but this one had the running gear from an S15 Spec R.

That means an SR20DET, a six-speed transmission, and the viscous limited-slip differential in a body weighing around 2,750 pounds. It was immediately at home on canyon roads and shorter drift tracks, where Adam beat it mercilessly for the his first few years of ownership.

It even got the S15’s gauge cluster.

At the time, he was crewing for Valkryie Autosport/GOTO Racing, then running a Nissan R35 GT-R in various time attack series. Inspired by the challenge he was partaking in, he decided to take his recently acquired S13 and try the road course for himself.

Being light, moderately powerful, and rear wheel-drive, the S13 had the bones to become a track car. He called upon his experience and added some budget basics to free up a few horsepower and find some support.

For the power adders, he grabbed a trio of no-name budget bits: a 4” turboback, a front-mount intercooler, and a manual boost controller. Good enough for a healthy 220 horsepower at the driven wheels, which, after stripping the interior and stuffing a Joshua Sher half-cage in there, made for a pretty punchy machine. Great torque and a much wider powerband—one perk of the S15’s variant of the engine—propel this 2,600-pound car at a surprising rate. It’s not just about peak power, but mass, gear ratios, and available traction.

Forget Fancy Stuff

That last trait benefited from the first major handling improvement: 5Zigen FN01RC wheels wrapped in a staggered set of Toyo R888Rs—235s up front and 255 in the rear. To make the most of the wider footprint and improve support, he added Fortune Auto 500 coilovers, SPL tie rods, and a no-name front swaybar bought off eBay. Remember when an S13 was a budget sports car?

Even without primo parts, the package was enough for fast laps without any drama. However, it was nearly stock in other areas, and that became a problem when the factory S14 one-piston brakes would vary wildly from corner to corner, even with upgraded pads. Additionally, the VLSD’s tendency to peg-leg limited a lot of his corner-exit potential. Not perfect, but not too bad for what was essentially a stock car.

Life was stress-free a long time; going to track days without breaking the bank, running full laps without worrying, and putting in respectable times. As his confidence grew, Adam started to wonder if a few aero pieces might not make a massive difference. Adding an Alumalite splitter and an NRG rear wing spruced up the basic shape of the Silvia, but the aero change worsened his confidence.

Some inspection from the sidelines showed that the trunk was flexing under the pressure of the wing. This was due to a lack of trunk reinforcements, which, when added, made a huge difference. The balance went from being skittish at higher speeds to neutral with a hint of understeer in the fast stuff; something easier to lean on when learning the basics. It also helped cut about five seconds off his previous bests.

Adam recognized that what the car required was a little fine-tuning at this stage. Switching from Toyos to a set of Advan A052s proved to not only give him longer stints before the tires’ performance would dwindle, but after playing with pressures for a few lapping days, he found that he was getting much closer to that reassuring sort of balance he’d been after for some time.

By getting the preloads, ride height, and cambers correct, he was able to feel at ease while pushing. When the rear stepped out, his drifting experience came in handy. Even though the of the suspension wasn’t widely adjustable, he could get it to do what he wanted it to.

He took it to Global Time Attack twice, both times competing in the Limited Class—a best of 11th in 2020.

Resurrecting the Silvia

His business SwanSpeed has picked up in the last couple years, so the trusty Silvia has taken a spot in the back of his garage. Though the engine’s been plucked from the bay, it’s not a cause for dismay. The reason it’s gone is because he’s finally found the sponsorship needed to make the car a front-runner in Limited.

The body’s been widened with Origin overfenders to run wider tires; 275s at the rear—hopefully enough to harness the power the new motor will make. The heart of the new build, currently in progress, is a TEM Machine IndustriesM-built SR20 with forged internals, a quick-spooling turbo, E85 capability, and with any luck, a little over 500 horsepower.

The Silvia might not have the traction of some of its rivals, but it’s an underrated chassis in a grip setting. It doesn’t have much mass to push around, nor does it have many vices. Provided the brakes and differential are replaced for something a little stronger, Adam might be able to give his inconspicuous Silvia a fighting chance against the S2000s and GT-Rs. Not terrible for a car with less than ten grand invested.

A big thanks to Horsepower Industries for their endless support.