Calling something a “Swiss Army Knife” implies it can cover a broad list of generic tasks without really excelling in anything specific. But is that necessarily a bad thing? The second part of the E82 Dudes builds continues with a 135i that aimed to prove a Swiss Army Knife car can be goal. A 2009 model year, this vehicle featured BMW’s twin-turbo inline six N54 engine. People familiar with the platform can tell you about how BMW’s first mass produced turbo charged engine is the predecessor to the N55 and the grandaddy of today’s B58 powerhouses. People less familiar can guess that as BMW’s first attempt at a large production turbo engine, it came with some kinks to iron out. While forged internal components made this engine a dream for tuners capable of reaching north of 600hp with bolt-ons and software, the plastic components surrounding the engine made it a dream for dealerships and indy shops everywhere. Seventeen years later, the result is a love/hate relationship from the public, with forums and social media posts both singing its praises and cursing its name. Boiling this information down results in one certainty; if you want to make performance mods, you need to address the maintenance first.
This 135i is the second of two E82 projects we embarked on what we have been calling the "E82 Dudes" series. The 1 series BMW has always had a bit of a niche market. Small and nimble compared to other BMWs of its generation, but never really given the same love as its more well-known brothers. To be honest, we overlooked them a bit in the past ourselves, but that all changed with these projects.
Luckily, Black Forest Industries has long offered brands and products to help BMWs in both departments. First to be replaced were the big three gaskets- valve cover, oil pan, and oil filter housing. If your N54 leaves a puddle of oil behind, chances are it’s coming from one of those three. Rod bearings, water pump, and thermostat replacements were also completed while the oil pan was off. The index-12 injectors were already installed, sparing a large portion of the budget, but the tired coil packs were replaced with fresh Dinan coils to help assure against misfires. The troublesome OE radiator, expansion tank, vent hose, and “Mickey Mouse flange” were also replaced, making sure the coolant would remain where it’s supposed to during sweltering NC summers.
With the car running strong but still fully stock it was time to see for ourselves what all the fuss over the N54 was about, and our friends at Burger Motor Sports had the perfect solution for us in their 500hp kit. The kit included their proven JB4 software with Bluetooth connector, which allows you to change maps, read/delete codes, and monitor a wide variety of gauges all wirelessly, all on the go. Ours also came with a Walbro Stage 2 Low Pressure Fuel Pump, BMS Dual Cone Intakes, BMS aluminum charge pipe with an authentic TiAl blow off valve, NGK 2-step colder spark plugs, feeler gauges, a fancy gap tool, decals, a plate frame, magnetic phone mount, and a big ass BMS 7.5” stepped intercooler for all single turbo future-proofing needs, and all for less than $2,000. BMS also included their aluminum replacement vacuum cannisters, a pair of blue cowl filters to match the DCIs, and some gorgeous blue anodized aluminum hardware to dress and tidy everything up under the hood. A set of high-flow 3” downpipes were also installed to let the engine breathe and sound better. To hold all the power better the car received BFI’s Stage 1 motor mounts, which included recent revisions to soak up more vibration while keeping the engine stable and the driver connected. Paired with a set of street-density transmission mounts, the results were more dramatic than we had imagined. The car sounded better and pulled significantly harder. The power just didn’t want to quit, despite still being on stock turbos. But with reduced slop in the drivetrain, all that power somehow felt easier to control.
Suspension / Wheels / Brakes
With the hidden potential of the engine now unleashed it was time to shift focus to keeping that power in the driver’s hands. When it comes to suspension, there was an obvious choice- ST Suspensions XA coilover kit. The XA kit offers not only ride height adjustment but dampening adjustment as well, to let drivers dial in the feel. The only thing left to be desired from the XA coilovers is adjustable camber plates, like on the XTA+3 kit installed on our 128i build. This is where having access to a CNC mill really comes in handy. The team at BFI were able to fabricate and install fixed camber plates and use the 135i as a test bed. The prototype camber plates were designed in three increments with 1.5*, 2.0*, and 2.5* negative camber offerings. This car went for the middle and uses the 2.0* plates. The entire underside was also renewed thanks to Whiteline’s Entire Vehicle Refresh Kit, which came with almost 40 new polyurethane bushings to replace the worn OE rubber.
After all this the build was almost overdue for a problem, which finally came in the form of wheel sizes. BMW spec’d an 8.5” wide rear wheel with an ET52 offset on 1’ers, greatly limiting aftermarket wheel options. Fortunately, it was discovered a while back that the narrower hubs from a 3-Series can fit a 1 -Series and reduce track width by about 10mm per side, opening a ton of possibilities including Rotiform’s TUF-R wheels. The car ultimately ended up running a set of 18”x8.5” ET45 wheels in the front with 18”x9.5” ET38 in the rear, stuffing an extra inch of width in over the staggered factory sizes. After wrapping the new Rotiforms in Kumho Ecsta PS91 225/40 front and 255/35 rear tires, a set of 10mm BFI wheel spacers was all that was needed to hone the fitment in the front. The rear setup rolled off the lift dialed in, and the car sat perfectly. .
The final hurdle was braking. The 135i already came with some impressive brakes, sporting 6-piston Brembo calipers over 338mm rotors in the front and 324mm rotors under a single piston caliper in the rear. The issue was that the hub swap left the team in need of a rotor with a 10mm shorter hat- a size not available in North America. The perfect sized rear rotors ended up being an option on the 130i in Europe, so a set was purchased and shipped across the pond. While there are 130i performance slotted options available, they are all non-symmetric or side-specific options. Seeing another opportunity to showcase their CNC capabilities, a set of blank European rear rotors and US spec front rotors was ordered in the same Geomet finish and slotted and dimpled in house with a directional orientation. The scratched calipers were repainted blue before being reassembled using ECS stainless lines and EBC red stuff brake pads. The result was a set of large brakes that stopped even harder than they looked.
Interior / Cosmetics
The last ingredient in the recipe for any good build is the seasoning, usually in the form of cosmetic changes. This car was currently a bit of a sleeper, with most of the mods being internal details. While everyone can appreciate a good sleeper, OEM+ has long been the standard at Black Forest Industries and this build would be no different. The interior was in excellent condition for a 14-year-old car, so BFI stuck with the basics. A Black Forest Industries shift knob is always a great place to start, and the team went with a GS2 heavyweight knob in black with gray Alcantara. Weighing in at over 400g, the knob really complemented the prototype dual-shear gear select rod, a combination that gives confident shifts and all but eliminated any factory play in the shifter. The knob was matched with gray Alcantara shift and e-brake boots, stitched in BFI’s in-house upholstery room, to breathe new life into the cabin.
An LED interior light kit was added to illuminate the minty interior better at night and the work inside was finished. The exterior of the car had a few more check marks on its list. Moving front to back, a pair of gloss black kidney grills replaced the stained chrome ones from the factory. The Xenon headlights were blacked out in favor of the OEM+ look, and a pair of smoked LED side marker lights replaced the ancient, frosted ones already on the car. A pair of faux carbon M-style mirror caps were purchased and installed, where it immediately became apparent that they should be wrapped in the same gloss black vinyl that covered the roof. The auto-dimming side mirrors themselves had been fried long ago and were traded for a set of blue tinted blind-spot mirrors. Moving back, the same set of black-line Euro tails from the 128i build brought this car into the current decade and a gloss-black duck bill spoiler tied everything up perfectly. Since the original photoshoot, the car has gotten tinted windows and LED bulbs for the angel eyes. You can stick a fork in it, because with that the exterior is done.
So, what was the result of all this work? To state the obvious, the car is an absolute blast to drive. And while this car probably won’t ever set any track or lap records, you don’t really care when you fly through the rpm range and feel it hit boost. While admittedly in the "driver" category at any show, it still turns heads anywhere it goes. It’s not the newest or flashiest car by a long shot, but it would still fit just right in a valet line. What this pocket-sized Swiss Army Knife of a car excels in specifically is making the driver crack a huge grin every time it starts, through every curve it carves up, and any time it pins you to the back of the seat, and that fun, that level of enjoyment is all that really matters.