This Smart Car Is A Scary-Fast Street Machine With Suzuki Hayabusa Horsepower

The tiny Smart Fortwo doesn’t have the best reputation here in America. Many people felt the car was just too slow and didn’t get good enough fuel economy. One man spent a year making what’s quite possibly the coolest Smart in America. This 2008 Smart Fortwo has the heart of a Suzuki Hayabusa and its performance will scare even the most fearless daredevils.

This Smart Fortwo is currently available on Facebook Marketplace with one of those listings where the seller won’t name an exact price. That’s annoying, but the car contained in the ad immediately made me perk up. I know this car!

This car was purchased new in 2008 and in 2009, Michigan-based fabricator Matt Boesch turned the little car into a total monster. It was supposed to kickstart an entire business, too, but then life got in the way. That may have never happened, but this car did, and you can enjoy its ridiculous sub-5 second 60 mph acceleration time if you dare.

The Build

I don’t need to tell our readers that Smarts aren’t exactly known for their speed.

The Smart Fortwo officially landed on the shores of the United States in 2008. Penske Automotive Group was the distributor and the company made some unfortunate decisions to streamline and cut costs with its new Smart USA. Over in Europe, Smart built faster-tuned Brabus cars and more frugal diesel cars. Smart Fortwo Brabus cars were known for their pep while the diesels got an honest 70 mpg in normal driving.

Sadly, Smart USA chose to give us a powertrain setup that was neither that fast nor that frugal. The company’s “one size fits all” solution was to give us a 999cc naturally-aspirated Mitsubishi triple making 70 HP and 68 lb-ft of torque. Truth be told, this engine is fine. These engines are known for their durability — better than the old Mercedes Suprex engines that used to power Smarts — and they can score over 40 mpg with a good driver behind the wheel. The EPA rated the Smart Fortwo at 41 mpg highway, which was at the time the highest rating any vehicle got without a diesel engine or a hybrid system. As far as performance? A 2008 Smart Fortwo could hit 60 mph in 11 or 12 seconds depending on conditions.

Unfortunately, Smart USA misjudged the market. While those in New York City, Chicago, and San Francisco found Smarts appealing for their ability to park anywhere, everyone else expected a bit more fuel economy or at least more speed. But for most of Smart USA’s run, we got neither.

Some people have been taking matters into their own hands by importing Fortwo diesels from Canada. I have one of those cars!

Those who cared less about fuel economy and wanted more speed quickly developed a whole tuning world for these cars. Within a short time fabricators and tuners began selling turbo kits, ECU tunes, bolt-on performance parts, and more. It seemed like just about everyone had a Doug Thorley exhaust, a Sprint Booster pedal remapper, and a cold air intake while more daring individuals dropped metal snails into their engine bays.

Among those fabricators was Matt Boesch, and he ran a small tuning shop he called Genius Parts. Boesch brought years of experience working in restoration shops and fabricating racecars to the Smart world. For years, Boesch’s parts, which included handcrafted metal mirrors, shifter paddles, armrests, and exhaust systems, were considered to be some of the best mods in the Smart world. My own cars used to wear parts welded up by Boesch.

In 2009, Boesch decided to embark on an ambitious project. One of the ultimate mods in the global Smart world is the motorcycle engine swap. Dropping a literbike’s engine in the rear of a Smart made the car far more rowdy than any turbo kit could do. There are plenty of videos out there of “Smartukis” and Smart Hayabusas doing all sorts of drifts, donuts, and straight-line drags.

Boesch and his friend Nick from Troy Laser became obsessed with having their own Smart Hayabusa and in March of that year, they started the SmartBusa project.

The project started by gathering parts. They had a new 2008 Smart Fortwo on hand, then they nabbed the 1298cc inline-four from a 2005 Suzuki GSX1300R Hayabusa. Stock this was an engine that made 175 HP and 102 lb-ft of torque, or around 2.5 times the power of a Smart, and that’s before any additional tuning. This engine was $2,700 from eBay complete with just 5,000 miles and an intact wiring harness.

Now, Boesch wanted to offer this conversion as a turn-key deal to future customers, so making the car able to be a daily driver was a priority. This meant giving the car a reverse gear. For that, Boesch nabbed a Powertec/Quaife differential for $3,200. Not only does this differential give the car a reverse gear, but it’s a limited-slip diff, too. A sort of weird quirk in going with this differential is that the driver could put the vehicle in reverse and run through every otherwise forward gear, which I wouldn’t recommend.

Boesch began by deleting the factory engine and transmission from the Smart. From there, Boesch went in a different direction than most builds. If you look at most Smart Hayabusa builds online, they tend to have wide bodies, wide wheels, custom subframes, and other expensive custom fabrication. Boesch bet he could utilize as much of the original vehicle as possible to keep costs down for that potential turn-key conversion business.

His build would utilize the original subframe, wheels, brakes, and suspension, but have a custom frame for the motorcycle engine that bolted into the original subframe. Boesch ended up finding out that he’d also have to make custom engine mounts, but he could reuse so much of the factory structure that the Suzuki engine would even utilize one of the factory engine mounting locations. Going back to the whole daily driver part, Boesch even thought about NVH and the engine has rubber isolators so it won’t vibrate your fillings out.

I’ll skip ahead here and note that Boesch gave the vehicle a stainless steel exhaust, a custom throttle and clutch pedal setup, and decided to build a sound-proof box for the motorcycle engine. On August 11, 2009, all of the crazy work paid off and the SmartBusa started up and drove for the first time. The project wasn’t done, but Boesch proved it was more than possible!

He even announced pricing for a turn-key kit. For $17,500 you’d get everything you’d need to convert your Smart to Hayabusa power. Toss in an extra $1,000 plus shipping and Boesch said he’d install it for you.

Unfortunately, in February 2010 and nearly a year into the project, Boesch had to pump the brakes. The car ran, drove, and was wicked fast, but the vehicle’s owner called it quits. Boesch was certain he had built the fastest Smart in America with a 60 mph acceleration time perhaps as low as 4.2 seconds and a gearing-limited top speed of 125 mph. He even achieved the goal of keeping the car somewhat daily-able with working heat and all electronics intact.

Final notes include the fact that the car lost a couple of hundred pounds thanks to the motorcycle engine being significantly lighter than the old Mitsubishi lump and Getrag transmission. Unfortunately, that meant the rear end sat high. Combine that with outrageous power, stock track width and stock tires, and you’ve got yourself one extra-squirelly Smart. Boesch reported the car felt like it wanted to swap ends under heavy acceleration:

[I]t is quite unstable and even a little scary under acceleration and high speeds. What I will strongly recommend to the owner of this car as well as future builds is a performance suspension as wall as wider wheels and tires. It needs these things to keep up with all of the added power.

This was the end of the road for the whole project. The car was gone and Boesch had the unexpected curveball of a wedding soon in the pipeline. Sadly, he had to move on from the idea of converting Smarts into Hayabusas.

The Car Today

Since then, Boesch’s SmartBusa has remained out in the wild. Nick sold the vehicle at some point and it seems like every couple of years I see it come up for sale. The car’s hard to miss given its SmartBusa badging and the giant insulated box with an engine in the back.

One year, I saw it in Michigan for sale for $6,000 or so and I should have bought it back then. I mean, Boesch spent nearly that in parts alone, forget about the labor to put it all together. But I missed out that time.

This time, it’s for sale all of the way east in Vincentown, New Jersey. The current owner doesn’t appear to be from the Smart world, but the SmartBusa still looks as good today as it did back in 2010. Unfortunately, it’s not so cheap this time around. The seller says they want “mid-teens” for it but then also drops a list of trades ranging from Porsches, Polaris Slingshots, Nissan Skylines, and other vehicles worth way more than “mid-teens.” So who knows what will actually bring this car home.

The seller does say the vehicle comes with upgraded wheels and tires to somewhat hold the power. The wheels here are Genius Darwins, which are really just rebranded TSWs. These wheels aren’t that wide, so I would expect the previous stability problems to be present. That lack of stability is also probably why this car has seemingly had a billion owners since getting finished.

As for Boesch, he’s still doing what he loves best. His shop is now called B2 Fabrication and he does a bit of everything from custom exhausts to overland Porsche 911 builds. Boesch’s builds were such a big deal even the New York Times wrote about them.

Still, this is quite possibly the coolest Smart in America. While the lack of a widebody makes this car apparently scary to drive, I love how it’s a total sleeper. If you saw this going down the road, you’d probably think of it as just another Smart. Then, the nutty owner could open it up and stomp some legitimate sports cars, so long as they keep the blue side up, anyway.