throtl Built Their Employee’s Dream BMW M340i — Here’s the Full Build Sheet
Video by throtl — “Surprising Our EMPLOYEE with His DREAM CAR BUILD! BMW M340i.” We’re covering the build; all footage and credit belong to throtl. This is informational commentary, not the seller of any part shown.
Most project cars start with an owner and a wish list. This one started with a surprise. The crew at throtl decided to build one of their own employee’s daily-driven G20 BMW M340i into the car he’d always wanted — a full transformation handled as a team effort with a stack of well-known partner brands. The result is a textbook example of how to modify a modern turbocharged BMW the right way: wheels and rubber first, then handling, then brakes, then breathing and cooling, with the cosmetics tying it all together. Here’s the full build sheet, part by part, and what each piece actually does.
The Platform: G20 M340i and the B58
The M340i is the sweet spot of the current 3 Series range. Under the hood is BMW’s B58 — a turbocharged 3.0-liter inline-six that’s become one of the most respected modern performance engines, prized for how strong and tunable it is straight from the factory. That’s exactly why it makes such a good build base: the powertrain is already quick and reliable, so a smart build doesn’t need to chase big engine internals. Instead it can spend its budget where a fast street car actually benefits most — the way it grips, turns, stops, sounds and stays cool. throtl’s build leans into that philosophy rather than fighting it, which is why the parts list reads the way it does. Our performance mods hub walks through the same order-of-operations for any platform.
Wheels and Tires: Apex on Falken
Nothing modernizes a BMW faster than the right wheel and tire package, and it’s where this build starts. throtl fitted a set of Apex wheels — a brand that’s become a go-to in the BMW world for lightweight, track-minded designs with correct fitment for the chassis. Wheels were wrapped in Falken tires to put grippy, well-regarded rubber under the car. On a chassis like the G20, wheel and tire choice is never just cosmetic: unsprung weight and tire grip shape how the whole car turns in, rides and puts its power down. To keep the new setup secure, the build also used Motorsport Hardware extended wheel studs — a stud-conversion approach that makes lining up and torquing wheels easier and more repeatable than fighting factory lug bolts. If you’re planning your own fitment, our wheels & tires hub and tire buying guide cover the trade-offs between size, weight and grip.
Handling: BC Racing BR Coilovers
With the wheels sorted, the suspension is where the car’s character really changes. The build runs BC Racing BR coilovers — an adjustable coilover system that lets you set ride height and damping to dial in both the stance and the handling together. Coilovers are the single biggest lever on how a modified street car feels: they replace the soft factory springs and dampers with a stiffer, adjustable setup that controls body roll and sharpens response, while still letting you choose a ride height that clears real-world roads. Pairing lighter wheels and stickier tires with a proper coilover setup is the classic recipe for making a fast BMW feel genuinely planted rather than just lowered. Our performance mods hub explains how springs, dampers and ride height interact.
Brakes: EBC
More grip and more corner speed demand more stopping power, so the build upgrades the brakes with EBC Brakes components. Better pads and rotors are the sensible way to back up a handling package: they give more consistent bite, better resistance to fade when you’re driving hard, and a firmer, more confident pedal. It’s the kind of upgrade that doesn’t show up in photos but completely changes how comfortable you are leaning on a quick car. Matching your pad compound to how you actually drive matters more than most people think — see our brake refresh hub for how pad compounds change the pedal and the dust.
Breathing: AWE Tuning Exhaust
The most audible change on the whole build comes from AWE Tuning, which supplied the exhaust. On a turbocharged inline-six like the B58, an aftermarket exhaust is chosen mostly for sound and flow — it wakes up the engine’s voice, gives it a deeper, more purposeful note, and lets it breathe a little more freely on the way out. AWE is one of the best-known names in the BMW exhaust space precisely because it manages to add character without turning a refined daily into something that drones on the highway. It’s a defining mod for a car like this: the M340i already has the performance, and the exhaust is what makes it finally sound the part.
Cooling: CSF
Turbocharged engines make heat, and heat is the enemy of consistent performance — which is where CSF comes in. CSF specializes in upgraded cooling hardware, and adding uprated cooling to a B58 helps the engine hold steady temperatures when it’s worked hard, whether that’s spirited canyon runs, hot-weather driving or the occasional track day. It’s an easy component to overlook because it does its job invisibly, but on a modern turbo car, cooling is what lets everything else keep performing when the temperatures climb. Keeping fresh oil in the engine is the other half of that equation — our oil change hub covers why clean oil is the cheapest reliability insurance a turbo six can get.
Protection and Finish: Pure PPF, Kies and Downstar
The finishing touches are what make a build look intentional rather than just modified. The paint is protected with Pure PPF paint protection film — a clear layer that shields the finish from rock chips and swirls, which is exactly what you want on a daily-driven car that’s now getting driven with more enthusiasm. Additional BMW-specific parts came from Kies Motorsports, a specialist supplier for the platform, while Downstar supplied dress-up hardware to clean up the details with tidy, color-matched fasteners. The build was brought together with help from install and detailing partners including Diamond Auto Salon, alongside components from HCP — the kind of shop-and-supplier collaboration that separates a cohesive project car from a pile of boxes in a garage.
The Takeaway: Build the Whole Car, Not Just the Engine
What makes throtl’s M340i work is restraint. It doesn’t lean on the B58’s tuning headroom to chase a big dyno number; it spends the build on everything around the engine so the whole car improves together. The wheels and tires set the tone; the coilovers deliver the handling; the brakes back up the cornering; the exhaust gives it a voice; the cooling keeps it consistent; and the PPF and dress-up keep it clean and protected. That’s the real lesson for anyone eyeing a modern turbocharged BMW: the factory powertrain is already excellent, so the smartest money goes into grip, control and finish — the things that turn a fast car into a genuinely satisfying one to drive. It’s a great blueprint, and a pretty incredible surprise for one lucky employee.
Planning something similar? Start with our performance mods, wheels & tires and brake hubs — and keep the maintenance dialed with the oil change guide and tire buying guide.
