9,200rpm & Not A Rotary In Sight

The Best of Both Worlds

Let’s talk about the elephant in the room, before we really get started on this one.

This FD3S RX-7 isn’t rotary powered. It’s also not V8, 2JZ, RB26 or SR20 powered. With the 9,000+rpm rev limit, you would be excused for thinking there might be a bike engine lurking under the bonnet, but you’d be wrong. However, there is a turbocharger.

Every time we talk about an engine-swapped RX-7, we usually have to make apologies of some sort, but that won’t be happening this time. I think we’re all past that. As much love as most of us have for the rotary engine, they’re clearly not an easy motor to live with for a lot of people. Otherwise we wouldn’t see so many engine-swapped, either by choice or necessity.

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When Alvi bought this car in 2013, it was silver, automatic, and someone had previously attempted to steal it, causing damage to the door locks, ignition and wiring. It was also misfiring.

That’s a far cry from the car which drove up the sun-soaked hill in front of me to our pre-arranged meeting place one evening last week.

With Alvi having kindly agreed to meet me after work, there wasn’t a lot of time for pleasantries as we only had around an hour to shoot before the sun dropped below the horizon. Unusual for Ireland in September, the sun was actually visible, so I wanted to make the most of it.

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Initial impressions? I still maintain that while Rocket Bunny and Liberty Walk body kits are played out online, they can still be done right and always look better in person. Before the car arrived, I must have watched 50 or 60 beige appliances drive past me. When Alvi turned the corner, I cannot overstate the impact his RX-7 had in comparison to what had preceded it.

Throughout the shoot, people of all ages who were out for an evening walk came over for a closer look and a chat. The FD3S is one of the most genuinely beautiful cars to ever have come out of Japan, and with the wide-body, it doesn’t look like anything that most people would ever have seen in real life before. The amount of interest it attracted was incredible.

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One of the first things I noticed is how the kit had been smoothed before being fitted. Alvi removed the indents for the rivets himself, before bonding the kit to the car. He thinks it looks better, and he also doesn’t like the idea of drilling into the factory panels. I think he might be right.

The rounded style of the Rocket Bunny kit works well with the Mazda’s sweeping factory lines, and the smoothed flares don’t detract from these.

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I’m getting ahead of myself, because naturally, none of this happened overnight. The Mazda has been a constant project for Alvi, and continues to be one today. Asides from a few select specialised jobs – such as wiring the engine, fabricating the exhaust manifold for the turbo conversion, ECU mapping, a differential rebuild and actually laying paint – everything else on the car has been taken care of with Alvi’s own two hands.

To give you a better idea of what was involved, let’s go right back to when he bought the car again; silver, automatic and misfiring.

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With the factory 13B turbo engine out and apart, it became apparent that it had previously been overheated. Alvi suspects it might have been low on oil too, but regardless of what caused it, it needed to be rebuilt.

With the cost of an engine rebuild priced, he made the decision to swap the engine instead. He had always loved the Honda S2000, but the car was just too small for him. You can see where this is going…

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With a crashed S2000 bought from the UK, Alvi set about swapping the F20C and its 6-speed manual transmission into the RX-7. The conversion took him around four months, with the biggest challenges being the front subframe and engine mount modifications, relocating the steering rack, and installing a hydraulic power steering pump as the S2000 featured electric power steering.

With the car running (it was still naturally aspirated and silver at this point), Alvi put the car back on the road and enjoyed driving it for the summer.

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A year later, in 2016, he made the decision to build the next evolution of the car with forced induction. For this, Alvi shipped the car to his native Lithuania, where HondaTuning.lt carried out the turbo conversion, including a custom exhaust manifold, down-pipe, intercooler, wide-band and mapping.

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The AP1 F20C engine was modified slightly to take boost, primarily with the use of a Mahle pistons to lower the compression ratio from 11.7:1 to 8.9:1 and to match the FRM cylinder walls. AP2 F22C valve retainers and Skunk valve seals replaced the original AP1 items, ARP head studs fasten the head and block, and Grams 750cc injectors supply the extra fuel required. Engine management is now taken care of with an AEM Series 2 ECU. The engine’s rev limit is an almost rotary-esque 9,200rpm.

With just 1.0bar (14.7psi) of boost, the engine made 403hp. When the car returned back to Ireland, Alvi described it as ‘dangerous’. The RX-7’s then factory 205/50R16 tyre specifications were no match for the addition of BorgWarner’s EFR 7163.

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These traction problems weren’t unexpected, so to solve them Alvi made the decision to go wide. Not one to do things half-hearted, he started by stripping the car down and undersealing the underside to protect it from corrosion (because Ireland). Then came the aforementioned smoothed Rocket Bunny kit, and finally a full respray in Formula Red, a famous Honda colour.

The SSR Professor TF1 wheels were ordered directly from their maker in Japan, and measure 18×9.5-inch -26 (front) and 18×11.5-inch -52 (rear) with 245/35 and 285/35 tyres front and rear respectively.

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Transmission-wise, a custom prop-shaft was required to connect the S2000’s 6-speed to the RX-7’s rear end, which houses a Cusco 1.5-way LSD. The clutch is a ceramic six-puck ACT unit, which required a custom clutch master cylinder to match the Honda’s pedal ratio.

Incidentally, this is the car’s second S2000 transmission, after Alvis sent second gear to the Moon last year during a hard launch. You’ll have to excuse him for not performing a full-bore launch later in this feature.

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The interior remains – delightfully – almost completely original, save for the Nardi wheel, AEM air/fuel ratio gauge and S2000 shifter. Oh, and the S2000’s fully-functional gauge cluster. Neat.

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The exterior is more than just a Rocket Bunny kit, too. There’s the much sought after ’99-spec front bumper, a Japspeed carbon spoiler blade with custom legs, an original Mazda roof spoiler, a ducktail spoiler, and a Fujitsubo axle-back exhaust (the rest of the system is custom) poking through the modified Rocket Bunny diffuser.

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Suspension-wise, the car is mostly stock with the addition of BC Racing BR Series coilovers. I don’t have a weight figure to hand, but I’d think the difference between the original turbo 13B and turbo F20C would be fairly negligible in a street car – correct me if I’m wrong.

The RX-7 retains its original Mazda Sumitomo 4-piston brakes.

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Despite owning the car for almost seven years at this point, there doesn’t appear to be an end in sight for Alvi – but that’s by choice. “It drives great and it starts every time, but there’s still more to come,” he told me.

These plans, at the moment, include sourcing a thicker radiator to improve cooling, changing the layout of the air intake and intercooler piping for improved air flow, and ultimately seeking out more power from the setup, with 500hp being the next goal for this project.

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What I selfishly almost enjoy the most about this car, is that so many people here don’t even realise it exists, and even less realise that it’s Honda powered. While Alvi has documented the build on Instagram, social media hasn’t shaped the project or dictated its direction.

Alvi built the car for himself. He enjoys it for the summer months and then puts it away for the winter to protect it and make some upgrades, before rolling it out again for the next summer even better than it was previously.

So it’s not a RX-7 for the purists, but luckily, there’s still plenty of original examples around. I don’t write that with any sort of malice or anything; I’m thankful there are plenty of rotaries in the world, but I’m also thankful that Alvi has built this. In fact, if the rotary engine never existed, it wouldn’t be a stretch to think Mazda would have developed something similar to the F20C to power its RX series of sports cars.

The sun had finally dropped below the horizon before I waved Alvi off, the sound echoing through the trees long after he disappeared out of sight. I look forward to seeing the car again in the future, and to find out if Alvi reached his next goal with it, or whether he’s changed tack and is going to take the car in another direction altogether.

I think it’s always good to keep people guessing.

Paddy McGrath
Instagram: pmcgphotos
Twitter: pmcgphotos
paddy@speedhunters.com

Gallery

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