First gear, second gear, third, BANG!
“My tuner did me dirty,” Adam said, describing the explosion that preceded the very last time his Impreza would be motivated by a Subaru boxer powerplant. The car had already swallowed up four engines – its factory 2.5L, a JDM STI Version 7 EJ207 and two Version 9s. For a street car that’s an awful lot of motors to send to the scrap heap. Enough was enough. “I could do another Subaru motor for upwards of 20 grand or…”
Bank account well and truly ravaged, when Adam considered a new engine, Chevrolet’s LS V8 topped the shortlist. That makes sense, because with LS motors you know exactly what you’re going to get. Adam wanted at least 400 wheel horsepower, and in the LS engine world 400whp is a very moderate ask.
What LS motors lack in creativity they make up for in reliability and simplicity. They’re a journeyman motor that will run on piss and vinegar – or at least standard octane fuel and halfway-decent spark plugs. As a swap candidate, the rub is that they’ve gone from impressive to almost expected in many cases.
The funeral for Subaru engine #4 took place just as the opportunity arose for Adam to start his own mechanical workshop. The shop needed a calling card, and with the right engine his Impreza could be just that.
Throw a stone at any local car event and you’re likely to hit someone capable of doing an LS swap on most platforms. I should know, I’m one of the people who would be hit by said rock. Again, no disrespect to those doing LS swaps; they just don’t ring off as uniquely as they used to. Toyota 2JZs on the other hand, while also becoming common, still do hold a level of mystique around them.
All told, the 2JZ-powered Subaru took about three years to become roadworthy. Work was split between Adam and two friends, but when the dust settled on engine #5 only two of the three relationships survived the ordeal.
Life tip: If you find it necessary to drill and tap the engine block of a freshly-swapped 2JZ, do mind the metal shavings. Also worth noting: If you try to evict said shavings with a can of brake cleaner, don’t let the straw fall inside the hole you just drilled. Above all else, if all of the above does happen at least own up to your mistakes. Because even the best ‘it wasn’t me‘ isn’t enough to save a friendship after the motor self-destructs on the dyno.
Thankfully for the rest of the build he had his devoted friend Erich Obermier along for the ride.
Engine #6 is a Titan Motorsports sourced factory original 2JZ-GTE with HKS 272-degree cams. As with most 2JZ swaps, the factory twin turbos have been swapped for a considerable-sized single, in this case a 72mm BorgWarner. Factory Subaru fueling has been replaced with a trunk-mounted aluminum fuel cell and an aftermarket pump. In the engine bay, a Radium fuel rail is fitted with high-flow injectors.
Backed by a Toyota V160 6-speed transmission, the engine – sans straws – put down 655whp, well eclipsing Adam’s original 400whp goal. This engine is also in good tuning hands thanks to BrenTuning and Turbo Mike.
The power hits the ground via a Ford 8.8-inch IRS rear end, a unit as close as you can get to a modern-day Ford 9-inch. They’re incredibly stout and easily accessed.
One rather significant drawback to Ford rear ends is the Ford 5×4.5-inch bolt pattern. Not in any hurry to buy two sets of Work Meister S1 wheels, Adam embarked on a rather complex journey of making both the front and the rear of the car share the same bolt circle. If you consider the hub the center line, the inside of the axle of the car consists of Ford parts and the outside consists of Subaru parts. Mating the two worlds together took a careful mix of parts from both OEM catalogues and The Driveshaft Shop. The considerable effort proved to be worth it as not only does the bolt pattern match, it’s proven to be extremely dependable throughout all of Adam’s sanctioned and ‘responsibly supervised’ road testing.
The factory RS brakes have been replaced with STI units, and for safety during all testing exercises a line lock has also been installed.
Considering what is under the hood, the exterior of the Subaru remains rather simple. Adam does have a Varis kit for the car but he’s decided not to fit it for now. Taking the Impreza off the road for a body revision is decidedly less fun than driving it. The car is also reasonably clean throughout, so adding an elaborate kit is perhaps unnecessary.
Personally, I enjoy the restrained exterior. It suits the interior which is strictly business.
The 2JZ engine is nowhere near the size and shape of a boxer, and Adam says the process of fitting the motor and transmission into the car was “cut and go”. Most of the factory floor no longer exists; it’s been replaced with custom bead-rolled panels from firewall to rear footwell. This style of floor is more commonly seen in drag cars, so isn’t entirely out of place here.
“Originally, the car was going to be more drag-oriented,” Adam described before admitting “it’s a bit of a weird mix of street and drag currently”. It’s still got a bit of a way to go before it’s ready for quarter-mile passes, but the bones are there should that become a goal again.
‘Bones’ in this case start with custom front and rear subframes that were a necessity to make the swap work. The unibody was reinforced before a cage was then added to further increase rigidity. Finally, the core support has been replaced with an InkFab-built tube front end.
Make no mistake, this car is not for the faint of heart. Yes, it lacks refinement in several areas, but when the boost kicks in you’d better hold on to something.
Since his introduction to backroads at an early age via Toyota MR2s, Adam (@Mistertwo40) has always prioritized a fun-to-drive car above all else. I don’t think there’s any way to describe an Impreza RS with a 600+ horsepower 2JZ under the hood as anything but a damn good time.
Photos by Keiron Berndt