How did we get to the point where a 660-hp all-wheel-drive 1990 Honda Civic Si is not only a possibility but an honest street driven reality? Chalk it up to a few different things. The first is Honda’s unrivaled cross-chassis compatibility. The same compatibility that fueled an early ’90s engine swap phenomenon which continues to thrive to this day also contributes to the notorious theft rate related to just about any popular Honda model of yesteryear. The other factor is plain old homegrown ingenuity and a knack for figuring out how to make various parts work with one another that the DIY crowd relishes.
DIY Done Right
You can add Brandon Smith, owner of this 1990 Si, to that group of die-hards that tinker and test, wrench, and repeat until they find exactly what they’re looking for. He’s built and re-built this chassis multiple times and its current iteration is by far the most impressive. Clean and simple on the outside, it features an obsessively well-organized engine bay that plays host to a mix of custom and off-the-shelf performance parts that look better suited for competitive drag racing than your local freeway. But make no mistake, this car is a driver.
Smith and his hatchback joined forces back in 2007, and he wasted absolutely no time in ripping out its native single-cam heart to make room for a ZC swap (an engine with the same 1.6-liter displacement but with dual overhead cams). Not long after would come his turbo kit and around 300 hp, and for the next four years, the Civic served as his daily driver and weekend warrior. That initial taste of boost was just the beginning, and since that time he’s gone through 10 different engine configurations, all turbocharged, with the exception of a supercharger set up that would net just over 300 hp. With experience and knowledge gained over the years, things got rather serious and his long-term Civic eventually hit the 600 hp mark.
Boost by the Pound
Making power has never been an issue for Honda’s B-series family, but on the street, big numbers have often proven to be more of a curse than a blessing, an unforgiving reminder of the inherent uphill battle of straight-line, front-wheel-drive performance. Converting to AWD is nothing new, something first done many years ago and since then often talked about by hardcore Honda fans, but rarely attempted.
Today you’ll find far more supporting parts from various brands that offer bolt-in kits and accessories, much of which are based around the fourth-generation Civic’s wagon counterpart. Smith dove in well before the mainstream had taken notice, so he’s got a head full of experience from his hands-on efforts. Forget about bragging rights or getting it done before the next guy, the benefit here is his ability to apply that knowledge to a true streetcar that stacks miles regularly and isn’t a ticking time bomb.
Smith’s process of converting his Civic to AWD was a gradual one that began with a CR-V AWD transmission swap, followed by a custom fuel setup in the rear that includes a fuel cell and multiple pumps, all strategically placed to make room for the necessary rear-end changes that would eventually make their way to the chassis.
He adds, “the conversion consists of a bunch of custom parts, all built in-house and with the help of a couple of companies. Over time we swapped a lot of the parts that we used to get it up and going. Without Sone from S1 Built, it would have been possible, but much harder. I reached out to him and asked for help and with no questions, he jumped on board.”
To get all four wheels to cooperate with one another, the drivetrain is armed to the teeth and begins with an OEM Civic wagon differential and viscous coupler that’s been fortified with Smith’s own driveshaft and billet carrier bearings which he markets under his B&N Designs LLC brand. The aforementioned CR-V trans is fitted with Liberty face-plated gears (1-4), Speedfactory Racing’s “FWD2AWD” gear conversion kit, Competition Clutch, and MFactory limited-slip.
A Solid Foundation
The foundation for Smith’s 600 hp output is a GS-R engine block that’s with Golden Eagle sleeves and O-rings, housing an Eagle crank, rods, and 84mm Traum 10.5:1 pistons. Up top, a Portflow head is fitted with a Supertech valvetrain and factory-issue Type R cams. The engine formula chosen is simple, and entirely tried and true.
The excessive jam being produced comes by way of a Garret G30-900 turbo mounted to a Gonzo Motorsports manifold and overseen by a Turbosmart 60mm wastegate. Gonzo is also responsible for the water-to-air intercooler kit that uses a slew of painstaking pie-cuts to snake just beyond the up-pipe and wastegate bellow, then around the swirl pot and to the Skunk2 throttle body and intake manifold. Engine demands and logging parameters are established by AEM’s Infinity management and sent through a Rywire harness and helps churn out the 660 hp and a staggering 498 lb-ft of torque. Just to note, the vehicle’s overall weight should be around 2,400 pounds with the pilot on board.
The area right above the driver’s engine mount is now filled with a custom catch can that Smith offers under his B&N banner. At the firewall, the brake booster was eliminated and in its place, you’ll find a trio of Tilton reservoirs that support an aluminum CompBrake pedal box, which sits just behind a custom footplate in the cabin. Also inside, a fixed-back seat wrapped in OEM material holds smith in place while a lengthy extended hub puts the Nardi steering wheel right in front of him as he takes cues from a Racepack IQ3 digital display.
Mild on the Outside, Wild on the Inside
Other than the hood-exit exhaust peeking through, the Civic carries a relatively mild exterior. A square wheel set up consisting of matte black 16×8 CCW Classic wrapped in 225/45 Toyo Proxes R1R poke out from the fenders slightly. The poke isn’t chasing the Instagram-promoted, cringe-inducing extreme wheel fitment trend, but rather to get as much contact patch as possible without going too far overboard. Even with AWD firepower, the lightweight hatchback is a terror and demands not only Smith’s undivided attention but also his experience behind the wheel.
It’s really nothing new to see the Honda crowd figure out how to adapt cross-platform applications in order to maximize performance, that’s what the community has thrived upon ever since its formation in the late ’80s. A build like Brandon Smith’s split-personality hatch, however, that’s able to cruise comfortably for hours or unleash all hell through its fortified AWD-converted drivetrain at a moment’s notice, certainly is.
1990 Honda Civic Si
- Owner Brandon Smith
- IG @wEFshitUP
- Engine B18C1 engine swap; Golden Eagle sleeves, O-rings, upgraded wrist pins, LS stroke; Eagle crankshaft, rods; Traum 10.5:1 pistons 84mm; Hasport mounts; Portflow headwork; ITR cams; Supertech valves; bronze guides, springs, retainers; Garrett Motion G30-900 turbo; Turbosmart blow-off valve, 60mm wastegate; Skunk2 intake manifold; Gonzo Motorsports intake, water-to-air intercooler, exhaust manifold; Radium Engineering fuel system w/surge tank; Walbro 450 fuel pump x3; custom fuel cell; AEM Infinity 508 management w/data log; Mac 4 port boost controller; Rywire Motorsport; wEFshitUP oil catch can
- Drivetrain CR-V AWD transmission, Civic wagon differential, viscous coupler; Liberty face-plated gears 1-4; Speedfactory Racing FWD-to-AWD conversion; Competition Clutch; MFactory LSD; wEFshitUP driveshaft and billet carrier bearings
- Suspension Skunk2 Pro 2 ST coilovers, shock tower bars, front camber arms; PCI rear camber kit; spherical bushings throughout
- Wheels & Tires 16×8 CCW Classic 2-pc.; 225/45 Toyo Proxes R1R
- Braking Wilwood DPHA calipers, pads, CompBrake pedal box; Tilton reservoir kit
- Exterior AMG silver paint; Carbon Trends SiR style hood; custom front lip, side skirts; ’88 Civic OEM bumpers, moldings
- Interior Racepak IQ3 digital cluster; Nardi blue stitch steering wheel; S1 Built AWD shift knob; custom floor plate; custom bucket seat with Si upholstery; Cheddas Auto shifter; GS-R lower center console and armrest; b-pillar brace; A’pexi turbo timer
- Thanks First shout out goes to my wife for staying down the whole time, thanks to Theo my tuner, thanks to Ryan at Rywire, Sone at S1 Built, Robert at Hush Performance; Art at Treadworks, Alberto at SB Machine, Bob at Golden Eagle, Pablo at Real Street Performance, Nader at Built 2 Apex, all my boys who stayed down there’s too many to list, my kids Brandon, Noah, Eli and my princess Savannah