FIts: 7/2012+ BMW 228i/328i/428i/528i/X1/X3/X4 with N20 4-cylinder turbo engine. See below for fitment on earlier cars.+ OEM-developed turbo upgrade, with input from BimmerWorld Racing+ Complete turbo + manifold + wastegate = easy bolt on! + Cooler intake charge even with more boost+ Reduces strain on other systems+ Gain power without sacrificing turbo life+ software tuning available to complete the upgrade – 400ft-lbs torque!You asked for a larger turbo that could flow more intake air at higher RPM, where the stock turbo runs out of breath, and that is what you got.

The N20 MHI Big Turbo is really a perfect upgrade for N20 engines. Increasing the boost with the stock turbo will quickly reveal its deficiencies – over-speeding the turbo causes more heat for not much more power, all while decreasing the life of the turbo. Heat is spread throughout the rest of the engine and accessories overwhelming the oil and cooling systems. The bigger MHI (OEM BMW) turbo allows more boost with less effort and heat.The MHI N20 turbo is the same twin-scroll design as the original turbo so boost lag is basically the same as stock, low and mid-range torque also does not suffer. The internals have been upgraded to flow better, especially at higher RPM. MHI went with a machined billet wheel instead of the stock cast piece for extra strength, lighter weight, quicker spool and improved durability. The bigger turbo flows more air even at the stock PSI so it’s not overworked, has lower system temperatures, moves a greater volume of air, and does not strain internal components. We’ve found this turbo makes noticeable torque and horsepower gains even without adding more boost – 20% more power across the whole rev range! If you are tuned for more boost the effects of this turbo are even more dramatic.This is a 100% bolt-on replacement, complete with the manifold, integrated turbo, as well as a new electronic waste gate assembly. It comes as pictured, and is the most complete and ready-to-install N20 Big Turbo on the market – and from the OE manufacturer! This is not a rebuild or a Frankenstein creation using recycled parts, like what the competition sells. And you’re not getting “half” of a turbo (like another popular tuner sells). You’re not swapping the “guts” of your current stock turbo either. Because the MHI Big Turbo is manufactured new, there is no core charge.Oil requirements: 5W30 minimum Change the engine oil after a 1,000 mile turbo break-in period.Fitment on pre-2013 cars with pneumatic wastegate (PWG): your original PWG and actuator arm must be transferred to the new turbo housing. The wastegate pot is a simple bolt on. The hole for the mounting pin on the PWG arm must be drilled out to 10mm. These are very simple modifications that should only take a few minutes to complete.