The Enduring Power of a Legendary Engine Even After 150,000 km

This time, I’m excited to bring you a review of a tuning car after a long break.

The car I test drove was a BMW M3 E46, and it turned out to be an astonishingly well-crafted custom machine. Previously, in August 2024, I reviewed the M3 CSL, a rare model with only about 150 units imported to Japan. The CSL is a special edition focused on weight reduction and enhanced driving performance, and I covered its excellence in that article.

This M3 is a standard model, but it’s been customized to the point where it feels like a self-built CSL.

From brakes and DME to the exhaust, suspension, and interior, every component has been meticulously upgraded. Judging by the photos, it looks aggressively tuned, making you brace yourself for a harsh ride. However, once behind the wheel, the experience completely defied my expectations.

A Ride Quality That Redefines Tuning Car Norms

The ride height is set very low, which honestly makes daily practicality challenging.

The risk of scraping the underbody is always present. Yet, in every other respect, this might be the most comfortable tuning car I’ve ever driven. Having driven many tuned cars before, this level of refinement stands apart. The suspension is quite stiff, but there’s no harsh jolts or vibrations at all.

The suspension setup is textbook perfect, delivering a sensation of gliding flat and firmly planted on the road. The combination of Aragosta coilovers and front and rear pillow ball upper mounts likely contributes to this. The front end responds sharply, slicing through corners with razor-like precision. However, this setup is clearly aimed at experienced drivers, and the current tires don’t quite match the car’s specs, making it a bit intimidating when pushed hard. Switching to higher-grip tires would make this an even more driver-friendly machine.

Engine Performance That Belies 150,000 km on the Clock

This car falls into the high-mileage category with 150,000 km, but as is often the case with BMWs and German cars in general, this mileage is no problem at all. The engine runs incredibly smoothly, spooling beautifully from the yellow zone all the way to the redline without hesitation. It feels like a car with only 10,000 to 20,000 km on it. The DME tune and upgrade from 32-bit to 64-bit systems surely play a big role.

The exhaust note is equally impressive. The combination of ASSIST equal-length front pipes, Supersprint center pipes, and titanium tailpipes produces a sound that’s far from the artificial tones of modern cars. It’s a genuine engine and exhaust roar that resonates deeply. Yes, it’s loud, but the quality of the sound is so pleasant it hardly bothers you. Driving this car is truly a joy for the senses.

M3’s True Character Unleashed in Sports Mode

The real essence of the M3 engine changes dramatically depending on whether you press the sports mode button or not.

In normal mode, it’s quite mild and manageable, suitable for city driving like a typical large-displacement 3 Series. But hit the sports mode, and everything changes. The engine’s revving, torque delivery, and especially the surge and responsiveness from low to mid-range RPMs transform dramatically.

If you don’t drive the M3 in sports mode, you’re missing the point of this car. The CAE Ultra Shifter installed has a long, racing-style throw. It feels great to engage, but shifting down from 3rd to 2nd gear requires some getting used to. It’s tricky to find the right pressure to slot into 2nd, and I couldn’t fully master it during the test drive. Still, the shifter’s positive, crisp engagement feels very authentic.

The True Value of a Well-Balanced Custom Build

The Brembo GT brake kit delivers outstanding pedal feel, and the chassis rigidity is more than sufficient.

Significant weight reduction has been achieved, making the car extremely agile and responsive to driver inputs. The OS Super Lock LSD 1.5-way combined with a 3.91 final drive ratio likely supports this nimbleness. The handling balance is excellent, and with slightly higher-grip tires, it would inspire confidence even at higher speeds.

For most drivers cruising comfortably on winding roads, the current setup is more than adequate. In fact, it offers such a refined handling and ride quality that you might feel like your driving skills have improved. I usually avoid featuring custom cars, but this one’s balance and craftsmanship compelled me to share it. Truly, an M3 tuning car of this caliber is a rare find.