BMW Tuning Specialist G-Power’s M440i Performance Package Outpowers The M4

Chances are, if you own something at least mildly sporty, there’s at least a few aftermarket options available for you to find more power, better handling, and a personalized appearance. For most of BMWs modern line-up, there are quite a few different parts and software upgrades to pick and choose and G-Power, a BMW Performancing tuning outfit that also works with Lamborghini, varous Porsche, as well as AMG models, has revealed a significant leap in power for the M440i.

The Gran Coupe, or four-door version of BMW’s 4 Series, packs a healthy punch from its turbocharged 3.0-liter, but power remains well below that of the more performance-focused M4, at least, until G-Power gets their hands on it. The group has come up with a performance formula that overpowers rear-wheel drive M4s and even flirts with the more potent M4 xDrive’s horsepower output.

Taking On The M4

Sift through G-Power’s website, and you’ll find a number of upgrades available for the M440i, including turbo replacements, software updates, exhaust components and more. Putting together some of these aftermarket parts has a dramatic effect on the B58 engine that BMW shares with Toyota’s modern Supra. The single turbo, 3.0-liter, inline-six is good for 369 horsepower with matching torque, but with G-Power’s magic applied, that number increases to 513 horsepower with 516 lb-ft. of torque.

Compare that to the rear-wheel drive M4’s twin-turbo inline-six, which offers 473 horsepower, and the G-Power version is well ahead. Bring the more powerful xDrive (AWD) version of the M4 to the fight, and the tuned M440i is just 10 horsepower shy, yet overshadows the true M4’s 479 lb-ft. of torque. A remarkable amount of power to be had for a street car that maintains its street manners and, from the outside, is indistinguishable from any other standard model beyond its enlarged exhaust exits.

The Power Struggle Made Easy

Instead of just bolting on parts and hoping for the best, G-Power has already done the heavy lifting by way of research and development, and has the package recipe sorted for you. The most powerful GP-520 package starts with a turbo upgrade using G-power’s GP-550 unit. Based on a stock turbo, it’s optimized for more boost using a bigger compressor and turbine wheel inside a larger CNC milled housing. The increased airflow and construction will support 450-550 horsepower.

Evacuating the increased airflow means a larger, more free-flowing exhaust and G-Power can supply both a downpipe, which connects to the turbo itself, and a complete exhaust system. Relieving the engine of back pressure, the stainless-steel downpipe includes a flex pipe for engine-to-chassis movement and a 300 cell sports catalytic convertor. That connects to their GP-DEEPTONE exhaust, also produced in stainless-steel, that relies on an exhaust flap to control sound and a pair of forged carbon fiber 90mm finishers to poke out from the rear bumper.

Throwing parts at an engine like the BMW’s B58 doesn’t automatically mean it will make more power or even run well enough to enjoy. To that end, ECU tuning is crucial and G-Power has handled that as well with their GP-500 performance software. You can bring the car to the company or ship the ECU to them, but only a G-Power authorized dealer can perform ECU tuning. With the added power comes added heat, and an aluminum 4 Series F3X charge-air-watercooler is the solution to keep temperatures manageable.

But Wait, There’s More!

If funds will allow, there are plenty of other parts to add to your M440i. Maybe you want to go in piecemeal and pick up something as innocent as a drop-in air filter, or something more advanced like aluminum charge piping, or high pressure fuel pump, all of which are also readily available to meet a variety of different tuning level needs.

Tuning goes beyond the engine bay, and there’s a carbon fiber steering wheel with LED race display built in, matching carbon shift paddles, high quality velour mats, and even a complete leather and alcantara cabin makeover that G-Power will customize to your preference. Then, there are wheel options, and, well, it never ends. Performance packages and individual parts are available now for the M440i and a host of others through G-Power’s website.