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 225/50R16 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

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wow I'm surprised we don't see this swap more often


This is a beautifully executed swap, would retain a lot of the handling as it's not a heavy LS lump, I would love to own one exactly like it, and an unmodified one just to experience both worlds. Thanks for a great article and stunning photos.


Lol, when will people learn the LS engines are not heavy? You do realize that the weight difference between a "complete" F20C engine and a complete LS1/2/3/LT is around 100 - 130lbs right?

I see this same silly comment made with LS swapped Miatas about how those who don't know think it messes up the weight distribution. It changes it by 2% front to rear. A difference that is completely un-noticeable.

I love this swap, don't get me wrong - but people need to abandon the misguided perception that an all aluminum v8 engine is some massively heavy thing - as it isn't by any means. LS series engines are very lightweight and given the power/torque are nearly unbeatable in a swap application (hence why they are so prevalent.)


This is what I call The 1978 Problem.

To too many fans of Japanese and European cars, American vehicles are stuck in 1978.

To these people, American technology has not advanced since the Carter Administration. To these people, every single American car is built to the quality, power density, fuel efficiency and handling standards of a 79 Malibu or 77 Fury.

For some reason, it's considered an article of faith that the Detroit Iron guy needs to get his head out of his ass and understand that Japanese and European cars are not the glorified golf carts of decades past, but that it's a perfectly acceptable thing for the Honda guy to hate all American cars because his great-aunt had an awful two-year lease experience with her 82 Celebrity.


The problem is just how toxic the car scene is. Because the LS Swap is the "easy way out" for a swap nowadays it gets downplayed because it's not getting the scene points it once used to. I love everything different and unique, but an LS Swap because of the accessibility to parts and info, plus cost, will always be the best bang for your buck. I say this as someone who spends all day telling people so stfu about LS swapping my LT1 Camaro when I ask a question online lmao


You know, as much as I like cars, my true calling is a sociologist.

I love knowing WHY people do what they do, and why cultures are the way they are.

So far, I haven't completely figured out just what it is about the very idea of "The Scene" that annoys me so much.

Doesn't matter what Scene - it's all Scenes.


Pretty dope!


I think it's the masterpiece that came form the land of the rising sun. The engine itself was a masterpiece but with all the drawbacks for daily use it's obvious that a lot of owners will run away from it, after all what it car culture without engine swaps? So having 1 of the best chassis with a very reliable engine (and in this case swapping the rotary to another legendary engine) doesn't reduce it's importance in the car world.
If done right, there should be no hate about it and this example is done perfectly.
Nice job Alvi, respect.


It might be blasphem, but it's blasphemy of the best kind.

I saw the title and thought to myself.... Could it be F20C? Then I laughed a bit at my idea and clicked the article. Turns out I was right?! Incredible build. I applaud you Alvo, and we!l written article Paddy. Why don't we see more of the smoothed out non-riveted somebody kits? In my opinion it looks way better than original, and it at the very least stands out much more!

Also, does anyone know what he used to bond the panels together? I'd love to be able to keep that included away for the future of my build...


Another point to remember is that the point of rivet-on overfenders was to make them easy and quick to replace when they were damaged on track.


I think the reason we don't see more blended body kits is three fold.

One is cost. It is cheaper just to rivet/screw/bolt the stuff on.
Two is trend. Some people like the "rougher" or "tougher" look.
Three is probably seeing improperly done blended/molded in body kits that over time where they meet the body it cracks/pulls apart due to substandard workmanship.

The most prolific adhesive is probably 3M panel bond. But as Dave said, there are many, many choices given application and usage scenario.


3m makes an automotive specific panel bonding adhesive, lots of body shops use it in place of welding. When used properly I believe it is supposed to be stronger than a welded joint.

I'm sure there's a similar product from retailers available in your area as well. Beware the automotive product rabbit hole can go DEEP.


This is...
This is...
I like it. Mad


As i clicked this i was fingers crossed thinking " please dont be a k20, please please dont be a k20 " .... yep :( , remember LS the world.... thats now K20 everything haha


And il eat humble pie as its a F20 XD


Stunning pictures of a stunning car. Great story too. Thanks!


You're welcome, and thank you for reading!


when I clicked on it, I knew it was going to be a Honda swap.

still loved it.


Beautiful dusk light photos in those shots and the kit looks so much nicer and more natural in it's smooth form.


As an FD owner I actually like this swap. I can live with this over an LS swap and it is reliable as well. Great choice.


The FD is one of the few cars where a non-factory engine actually IMPROVES its reliability.


The gauge cluster is a nice touch.


This is a sweet car. Damn near perfect in fact.

And notice how natural the F20 looks in that engine bay.


I'm loving the smoothed kit. I don't hate overfenders, but they frequently look unfinished unless the vehicle style dictates that the riveted style looks correct. I also know fully integrating and molding in is a ton more work and and is harder to swap kits making it not right for some. This smoothed overfender without visible mounts is gorgeous! It looks so much more finished. I wish I saw more WB kits like this.

Also, is it just me or does the fender profile, especially the front give a Dodge Viper vibe? I know this isn't the first RB kitted FD3 I've seen, but it strikes me more prominently this time.


I remember when the FD debuted and I thought it looked like a combination of a Viper and a Corvette, rendered in 3/4 scale.


Beautiful! The FD has timeless lines and this kit just improves on it.

Engine choice is great!

The lack of suspension and brake mods are slightly surprising considering the power-increase. More surprising is chasing power before improving aforementioned aspects. But heck I have no idea how this car is driven and where it is used for.

Truly a gorgeous car with power to match the looks.


It's worth remembering that it's still a street car, and the current suspension / brake setup is more than adequate. It's also an always evolving project!


Very true Paddy! When are we really ever finished with a project. These points may be addressed over time.

With that amount of power on tap you can literally expect to run into a situation you need a bit more stopping power.
But bigger breaks does not automatically mean better stopping power, it's about maintaining this force. And on the streets this repetition will be limited.

I guess we are so spoiled in seeing cars here that have the full Monty. And with a car that looks so good standing still who cares.


This is honestly such a perfect replacement for the rotary engine, keeps the weight behind the front axles where possible, revs as high as you'd realistically need has a big nagasaki noise maker strapped to it. yessir! Nice!


The stock tire fitment is 225/50/16

"...The RX-7’s then factory 205/50R16 tyre specifications..."

Kindof a silly swap, but nicely done it seems.


My fat fingers will be my downfall. Amended.


The car, the swap, the pictures. A Great article.


Thanks, Travis.


I honestly like these turbo Honda motor swaps a lot more than the LS swaps


I like anything that lets an owner drive and enjoy their car more.


Ok, first off...love the car. It's well done and a cut above most. Always good to start with the niceties even though I stopped caring about getting flamed in comments sections sometime in mid-2011.

I can never truly "identify" with builds here or elsewhere because no one seems to understand that less is more.
This build was certainly on the right track by smoothing the bolt holes on the flares and making tasteful decisions in regards to color and wheels. It's nearly a masterpiece.

-HOWEVER, the wing is infantile in in both presence and the quirky saying beneath it. The car would look ten times better without it.

-Similarly, the winglet poking up from the rear glass makes an otherwise elegant build look eBay cheap.

-Lastly, since the bodykit is so well sculpted that it almost looks factory, why not continue the aesthetic to the rear diffuser??? Truthfully, it looks out of place, but if it HAS to be there...at least paint the sides body color!


Approaching 500hp on those brakes make me nervous...


It shouldn't, they're a perfectly good caliper and with decent pads and fluids, there shouldn't be any issues on the street.


Thanks for the heads up!


Brilliant feature. I've always wanted an S2000 (ever since I got overtaken by one being skillfully piloted down and country road in Wales). This is genius. Thanks for sharing Paddy.


A proper Honda in the right hands is such a formidable car. I would love a DC2 because AP1 S2000s still frighten me.


I love using your shots as my desktop background but with these I feel like he is staring at me from inside the car.


He is.


Damn, now THIS is what I come to Speedhunters to see! Exceptional article, and I love how his build really is just for him since you don't see all the nonsense "sponsor" stickers you see on the rest of the "I bUiLT tHiS fOr mE" cars.


Holy Jesus.This is for a FACT one of the most beautiful things i've ever seen.I like how he just keeps the OEM seats,cool touch.In my opinion,this is a really good article for sure.