Both SUVs also have slightly more power and torque.
There are plenty of aftermarket tuners willing to modify the BMW X3 M and X4 M. AC Schnitzer has cranked up the power of the X3 M to 600 horsepower, while Mission Performance is developing a RWD version of the high-performance SUV for when you want to burn some rubber.
But if you just want the BMW X3 M and X4 M to sound more savage, aftermarket tuner Dinan is selling a new axle back exhaust system. With this upgrade, the BMW X3 M and X4 M sound just as brash as its larger V8-powered X5 M and X6 M siblings.
To enhance the SUV's soundtracks, Dinan's stainless steel exhaust system incorporates larger 2.9-inch tubing compared to the stock model's 2.7-inch tubing. It's also five pounds lighter than the stock system used in the X3 M and X4 M. This improves the airflow through the entire system and the outer pipes when the valves are open.
When the valves are closed, all gasses are forced into the muffler for sound deadening and exit the two inner tips. Since the X3 and X4 M can now breathe easier with Dinan's exhaust system, there are also gains in power and torque, but nothing as significant as we've seen from other aftermarket tuners. Dinan claims the axle-back exhaust system increases the power by up to 8 hp at 6,600 rpm and torque by up to 6 lb-ft at 6,600 rpm.
This equates to 481 hp and 448 lb-ft of torque in the standard X3 and X4, and 511 hp and 448 lb-ft of torque in the X3 M Competition and X4 M Competition.
Available with a black ceramic coated or polished finish, the new quad exhaust tips are also noticeably larger with a 4.5 inch diameter, but don't look out of place. According to Dinan, the tips utilize a new design with an inverted clamp neck, allowing for larger tips to be installed. The clamp is also almost completely hidden.
As you can hear in the video provided by Dinan, the BMW X3 M and X4 M sounds superb. Dinan is currently selling the polished and black tips for $2,299.95 on their official website.