For our K-Powered Theme this month, we’ve seen K-series engines powering all manner of machinery – from a Datsun to a Toyota to a shed-built single seater. Today, I’m taking you back to Honda’s tuning roots in the Kansai area of Japan with some retrofitted Civics.

As fate would have it, ASLAN hosted an event at Central Circuit a couple of weeks back, part of which included their annual Honda One Make Race, which would provide plenty of K-powered cars to choose from. I was mostly interested in the icons. I wanted to see some EF9 and EK9 chassis racers utilising the K-series motor, and I was in luck.

You can check the full event coverage from Circuit Festa and the Honda One Make Race here, but for this story let’s take a closer look at the cars I found with the help of Nabeshima-san and ASLAN themselves.

Honda’s performance K-series is such an unsuspecting little champion. It basically looks like any ordinary inline-four engine, but as with most things, it’s what’s on the inside that counts. Before writing this story, all I knew about these engines was that they handle power and can rev their little heads off all day long. After looking through some tuner websites, I can now really appreciate just how staunch the K-motor is.

First up is the 136 Concept CR-Z. This was originally a Spoon Sports demo car, but was later bought by its current owner, Isamu-san, who had ASLAN complete the K-swap. The idea of an ASLAN-rebuilt car wearing Spoon’s iconic colours and livery scheme seemed a little off, so the front half was changed from blue to red to keep the peace.

In factory form, and as a Spoon car, the CR-Z utilised its original 1.5L LEA engine with Integrated Motor Assist (IMA). In ASLAN’s hands, that hybrid setup was replaced with a K20A from a DC5 Integra Type R.

The fact that this car is now running a K-series is kind of a beautiful thing because, because way back in 2011, Dino featured this very car when Spoon had finished its first iteration (still white), and jokingly wrote that the only way to get power would be to swap in a K-series engine. Fate is a wonderful thing…

Under the red and yellow paint are carbon fiber doors and hood, with acrylic windows and Spoon aero mirrors helping with weight reduction. Isamu-san is still running the Spoon original roll cage and Spoon/Nissin monoblock calipers.

Even though I was hunting for K-series engines, I couldn’t help but snap these two handsome B-series setups. I think if there was an all-wheel drive option I could live without a turbo. These Civics look a riot and I think the charisma of the Honda engine is reeling me in, one electronically-controlled cam at a time.

This Petronas-liveried K-swapped EK9 Civic Type R was absolutely killing it around the track. Even with a stock K24, it was still overtaking on every corner, some sticky rubber and a set of circuit-spec Spirit suspension keeping it planted. I’m beginning to understand that light weight, balance and driver ability are the magic ingredients in making these cars fast.

Next up is another K-swapped EK9, this time Kouki Atsumi’s wild machine.

As soon as I found out I’d be shooting some spotlights at Circuit Festa, I knew I had to try and get some rolling shots on the actual track. Without hesitation, I messaged ASLAN to ask if it would be possible.

Like my parents used to say when I asked for something special, ASLAN said, ‘ask Central Circuit’. When I asked Central Circuit, they said ‘ask ASLAN’. So, to my complete shock, we all agreed to shoot the cars on track as a special treat for Speedhunters.

Considering the Japanese custom of running a mile at any kind of risk, I was pretty surprised at how relaxed these guys were about me sitting in the back of an open car tracking race cars on a circuit. But hey, Japan is full of surprises.

Time was pretty limited; I had two laps of warm-up formations and I could basically only shoot the front two cars, but the ASLAN guys had arranged it so that my two K-swap hero cars were in front. They’re not the best shots by any means, but that’s not what’s important. I’m chuffed with them because we made something special happen.

Kouki-san has built an absolute beast here, and while it may look half finished, I suspect there’s a reason for a full carbon front end and a stock rear end. He’s got a carbon fiber roof built by Osaka shop Auto Stage Close Up, who specialise in prepping and maintaining track cars, and is running Tein Super Racing suspension all round, with Spoon and DC5 Type R brake calipers front and rear respectively. The wheels are RAYS Volk Racing items – RE30s and TE37SLs.

Under the carbon fibre hood is a K20A that breathes through a Mugen air box, 70mm throttle body and a modified intake manifold. Waste gases exit through a Skunk exhaust manifold and a custom 70mm titanium exhaust.

The interior is a feast for the eyes, featuring a custom dash full of switches and gauges, exposed electronics and a Mugen roll cage. I particularly liked the little fuel tanks, just enough to get around the circuit and not a kilogram over. Kouki-san told me that the 10L tank is for time attack and the 20L tank adds more storage capacity for sprint racing.

Finally, we have an ASLAN-prepped, K24-swapped EF9 Civic SiR owned by Nishan-san. Arguably one of the best looking builds of the day, it was a real treat to see it resting in the pits, let alone to be shooting it out on the track, at times close enough to touch.

When we were planning our trip down to Osaka for this event, it was this car that we really wanted to shoot. With the help of Nabeshima-san, getting in touch with Nishan-san was pretty easy and he was more than happy to show me around the Civic.

ASLAN has selected a K24 powerplant and fitted FD2 Civic Mugen RR cams and Toda pistons. Also from Toda is the Sports Injection kit, a combined ITB and fuel rail/ injector system. Apparently, there are loads of benefits using independent throttle bodies like this system does, and although there is an obvious amount of power to be made all the way through the rev range, one of the biggest benefits is actually at idle and lower RPM. The individual intakes reduce intake interference between cylinders and give a smoother response when using big cams.

ASLAN have sprinkled their magic all over this EF9. Some of their custom parts include a polycarbonate windshield (cutting 5.2kg), and hand-built suspension developed with Spirit Performance.

To be fair, all the cars at Circuit Fiesta were super cool, whatever engine they were running. But it was definitely pretty special to spend the day with these guys and their K-swapped weapons. I think I’m definitely starting to ‘get’ the spirit of Honda and what makes them special.

Now, enough standing around the pits. It’s time to don race gloves and helmets and hit the tarmac for some more of those rolling shots. Enjoy them below…

Toby Thyer
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