The turbos referenced in this guide will fit both the N63 and N63tu models. However, it’s important to note a few significant differences with the engines. We wrote an in-depth post about the differences between the N63 and N63tu here. The main difference we want to focus on lies within the internals. The N63tu engine receives a forged crank and rods. Additionally, the N63tu features oil spray nozzles to help cool the piston crowns.
These differences make the N63tu a stronger engine overall. With proper supporting mods and tuning, the N63 and N63tu are capable of making similar power numbers. Though, the N63tu is better suited to handle higher horsepower. However, both engines have their limits. That leads us to our next paragraph. However, one more quick difference before we move on.
The N63 recently received flash tuning capabilities. Flash tunes are highly recommended to fully utilize upgraded twin turbos. As far as we are aware, N63’s must actually send in their DME’s for flash tuning. The N63tu is a much easier engine to flash tune. Bootmod3 N63 tunes are a great starting point, but you’ll need a custom flash to fully utilize the turbos.
It’s tough to put upper limits on any engine. This is especially true with the N63 and N63tu where not many are pushed to 600-700+whp. Additionally, torque plays a bigger role in an engine’s upper limits when compared to horsepower. Keep in mind – the more power and torque you push, the more risk you are taking on a stock engine. In general, we believe the “safe” upper limits of the N63 and N63tu are as follows:
There is, of course, still risk at these levels. Ultimately, it’s important to ensure you’re running a proper tune, fueling, and supporting mods. If you’re targeting 600+whp we highly recommend running meth, race gas, E85 mixtures, or a combination of those. Additionally, you may consider turning to limit torque on the lower-end and mid-range unless you’re building your engine. You can still make big power by shifting the curve right. We won’t go any further into that in this post.
However, if you’re looking for more info check out our S55 upgraded twin-turbo guide. If you scroll down a little bit you’ll see a section titled “S55 Top-End Power” followed by two dyno charts. The same basic concept applies to the N63 and N63tu, as well.
Alright, it’s almost time to dive into the more exciting part. However, one more quick topic to discuss prior. We highly recommend opting for 1-step colder spark plugs (NGK 97506) for upgraded turbo N63’s. Additionally, you may consider replacing your ignition coils if that hasn’t been done in the past 50,000+ miles.
Depending on your power goals you may be able to get away with OEM N63 spark plugs. However, 1-step colder plugs assist in transferring more heat away from the spark plug tips. Many modded N54, N55, S55, N63, etc engines run the NGK 97506 plugs with great success. Anyways, let’s move on to the exciting stuff.
**Generally, we prefer to find multiple dynos and different cars running each set of turbos. However, information for N63’s and N63tu’s running upgraded turbos is limited. As such, some of the horsepower numbers we use below are estimates and/or are taken from the manufacturer’s recommendations. Additionally, the power numbers assume you have proper tuning, fueling, and supporting mods.
BMW N63/ N63tu Stage 2 Upgrade Turbos
Pure Turbo UK builds some awesome turbos not only for the N63 but also many other modern BMW engines. Many run these turbos with excellent results. They’re without a doubt one of the most popular turbo upgrade options for all modern, turbo BMW engines. It’s hard to argue with the quality, price, and results of these turbos. Overall, Pure Stage 1 turbos are an excellent option for the bmw n63/ n63tu stage 2 upgrade turbos. These turbos are certainly capable of pushing the upper limits of the N63 engine. With proven results and a good price point, it’s tough to go wrong.