Update 10/18/19: This super supercharged 540iT sold for $11,100. Deal!
BMW’s continual refusal to bring the most powerful form of its its Touring/Sports Wagon historical lineup has been, as a 5-door enthusiast, pretty frustrating. That’s left Audi in the 2000s and Mercedes-Benz more recently to thoroughly dominate fast 5-doors, with the brief Cadillac interloper. But just because you couldn’t get an M5 Touring over here didn’t mean you couldn’t at least get M performance.
For that, though, you had to turn to fabled California tuner Dinan. No stranger on these pages, Dinan’s well-thought mods and clean execution earned his company a place in the revered showrooms of new BMWs. Cheap? Certainly not. Just the supercharger alone on this particular 540i was $16,000. But you get what you pay for, and the result when Dinan blew on the M62 was a claimed 400 horsepower. So this 540iT has the chops to back up its M5 looks:
It seems that with every progressive generation of BMW 5-series, the gap between the outgoing M5 and the top of the line non-M 5 series narrows considerably. While there wasn’t much of a contest between the E28 M5 and E34 535i, by the end of the E34 run the 540i M Sport was – for all intents and purposes – a M5 without the S38. BMW upped the ante to 400 horsepower in the new E39 M5, once again widening the gap to the 540i model. But the successor E60 545i offered 330 horsepower with matching torque in 2003 alongside the outgoing E39 and once again the gap in performance became much smaller. That gap was made almost imperceptible in 2005, when BMW revised the E60 with the increased displacement in the N62 motor.
Now sporting 4.8 liters from the N62B48, the new “550i” now had 360 horsepower and 361 lb.ft of torque – a near match for the S62. What was perhaps more amazing was that the new N62 also nearly matched the torque of the new E60 M5’s S85 V10. But while that screaming V10 produced far more horsepower, the peak torque was reached only at 6,100 revolutions – hardly practical in your daily commute. In comparison, peak twist on the N62 came at a much more realistic 3,400 r.p.m.s, and on the fly these 550is were – and still are – seriously quick sedans. They also introduced the next generation of design language and computer technology into the 5-series. Some love the look while others lambaste the design. While it’s certainly not my favorite 5, at least it’s distinctive and different in a world full of cookie-cutter designs and dare I say I think it may look better today than it did new – perhaps a testament to its avant-garde lines. While the lust-worthy V10 captures the imagination of enthusiasts, day-to-day the 550i is likely as fast 95% of the time and much cheaper to get into and run. Couple that with a host of Dinan upgrades and you’ll easily surprise M owners for half the price of the V10: