BMW Engine Parts for BMW X Series E53 (2000-2006)

All vehicles will lose some degree of performance due to heat soak under the right operating conditions.  Engine management systems constantly monitor operating conditions and modifying parameters based on sensor inputs. BMW integrated the intake air temp sensor in the MAF housing on models such as the E39 M5, and, being sandwiched behind a hot radiator and in some applications next to an even hotter valve cover, this is less than ideal for performance applications. Absorbing excess heat from its surroundings, the MAF can’t shed it fast enough, and the ECU reads an inaccurately high intake air temperature. Compensating for this false hot air measurement, the ECU pulls timing and runs a richer fuel mixture, resulting in a significant loss of torque.

What can you do?  Locate an intake air temp sensor in a location where it can properly measure incoming air temps and where it's less prone to heat soak. Mounting the sensor further away from the heat source and isolating it from the MAF housing, it can both resist the effects of heat soak longer and respond to temperature changes more quickly.  The result is you’ll experience reduced torque loss and more consistent power output when you’re pushing your engine hard. 

The Turner engineering team was initially skeptical of the claimed performance benefits of this modification. They first set out validate the functionality and performance benefit of a temp sensor relocation. Replicating stop-and-go traffic heat soak in a 2001 540i was a simple task in a controlled environment - their dynometer. First the car was heat soaked to simulate being stuck in traffic or moving at low speeds by running the car four times on the dyno with the dyno's cooling fans disabled. The fans were then turned on for three more runs to observe the recovery rate once air flow was reintroduced. The test: following this procedure once with a stock IAT, and once with their relocation kit in place. 

The result? Turner recovered 11lb-ft torque at 2500rpm through use of their relocation kit, with even greater recovery to be found for M5 owners. Here are the heat soak-related torque losses Turner experienced:

Stock IAT location:
18rwtq at 2500rpm
10rwtq at 3000rpm
9rwtq at 3700rpm

Turner IAT Relocation:
7rwtq at 2500rpm
5rwtq at 3000rpm
5rwtq at 3700rpm

**Click here for installation instructions**

The Turner engineering team designed a complete plug and play kit (unlike all other options on the market) that makes for quick, easy, and reversible installation. Weather-sealed connectors keep out the elements, while sheathed wiring offers a clean appearance underhood. With a harness nearly 3 feet long - the Turner IAT relocation kit offers flexibility in positioning, but not too long that you're left with unsightly excess wiring. Turner recommends positioning the sensor in a location away from engine heat, but still within the intake ducting to achieve accurate intake temp readings - such as the far side of the base of the airbox. Vehicles with cold air intakes with cone-style filters can even position the sensor in the end of the filter. Simply drill a hole in your (cool) location of choice and plug in the harness. More information including installation instructions and some good examples of sensor mounting locations can be found in our DIY PDF. 

We include everything you need to relocate your IAT, just select your desired sensor brand below - Genuine BMW or original equipment Beru.

Also the perfect plug-n-play option for anyone looking to upgrade their intake to utilize an Alpha-N tune!

Note for vehicles with M62 engine: applicable to 1999 and up

Upgrade your engine build with Turner's WPC-treated Race Series Bearings, engineered for serious performance enthusiasts. Starting with ACL’s high-performance bearing shells, these Race Series bearings are built to withstand extreme RPMs and stress. Utilizing a "Duraglide" tri-metal construction and a high-strength overlay plate, these bearings offer superior oiling and heat resistance for high-RPM operation.

Our WPC-treated bearings take ACL’s already impressive design and enhance it even further. The WPC treatment process strengthens and smooths the bearing surface by firing high-speed, ultra-fine particles at the bearing shells, reducing friction and improving durability. This advanced surface treatment ensures smoother operation and improved heat dissipation, which are critical for any high-performance engine.

Key Features:

Duraglide Tri-Metal Construction: ACL's Race Series bearings feature a high-strength overlay for enhanced performance. Optimized Oiling: Designed to promote better oil flow during high-RPM conditions. Precise Fitment: Manufactured with OEM-level precision using micron tolerance machining. WPC-Treated for Strength: Surface treatment adds strength and reduces friction for improved engine performance. No Flash Plating: Allows for better heat transfer and bearing retention. Thermal Discharge Process: Smoother, stronger components through WPC’s unique thermal discharge technology. Enhanced Heat and Friction Resistance: Built to combat the biggest enemies of high-performance engines. Don’t settle for standard bearings—choose Turner Motorsport WPC-treated Race Series Bearings for the ultimate engine performance upgrade. Perfect for your next engine rebuild or rod bearing service!

Underdrive Power Pulleys work to 'free up' horsepower. Any accessory that spins from the main drive belt is using up power. That's power that could otherwise be used to move the car. By giving some of that power back to the engine, you can make the car faster! It's like FREE HORSEPOWER!

Underdrive pulleys for your BMW will slow down engine-mounted accessories - the water pump, power steering pump, and alternator*. These systems contribute to 'parasitic losses' - power lost from what the engine could produce if it did not have these systems. Since less energy is used to move them, that power is transferred back to the engine and used to propel the car. Our pulleys give a 10-20% reduction in rotation, releasing up to 11hp on most BMW six-cylinder engines. There's also a small but noticeable improvement in throttle response too! We have done extensive testing and development work, both on and off the track, to ensure that the accessory systems function as they should. On our Racing pulley kits we actually underdrive certain components more so we feel our Street pulleys are an ideal compromise between power/torque gains, reliability, and system performance. Our pulley kits have been on the market for over ten years, and used in all of our own cars, with zero component failures related to their use.

Our pulleys are made from T-6061 aluminum and finished in a durable black hard anodize that is very resistant to wear, chemical exposure, and heat. We designed our pulleys to look similar to the factory parts but also to be stronger and, in most cases, slightly lighter too. For example, a Turner alternator pulley is less than half the weight of the stock steel pulley! With our hardcoat aluminum you will never have to worry about a serious failure of a stock plastic pulley. A 'stealth' approach to aesthetics was our goal and we let the results speak for the pulley design. Installation is straight forward and easy with simple hand tools. Removal of the fan is required for access to the front of the engine. Total install time for a 3-piece pulley set should be around 1.5 hours. A new longer belt is included and we also recommend replacing the separate A/C belt, belt tensioners, and the guide and deflection pulleys at the same time.

* Alternator Pulley Options

Bosch or Valeo? BMW built your car with either a Bosch or Valeo brand alternator. Unfortunately, the pulley is not the same for both brands. The brand is usually printed on the black plastic cover of the alternator but may be facing the frame rail or the ground. If you know which brand you have, select your option below and we'll send you the correct alternator pulley for your BMW. Don't know which you have? NO PROBLEM! We can send you both. The 2nd pulley costs $40 but you will receive a refund once we get the un-used pulley back (return shipping not included).

Stereo Systems. We offer our kits in two different ways: a full power kit with all 3 pulleys or a 2 pulley kit for people who do not wish to underdrive their alternator (for large stereo systems or other battery-draining modifications). Our kits have been tested to be compatible with the factory premium stereo systems (Harmon Kardon, etc). But any major alterations or upgrades from the factory system may work best with our 2 pulley kit and no underdrive of the alternator. Otherwise, the 3 pulley kit is recommended because it not only underdrives the alternator but the Turner pulley is much lighter than the stock one.


Additional Info

Clickhere for example dyno graph

To learn more about Turner Power Pulleys, click here.

This Power Pulley Kit Fits the Following BMWs:
2000-2006 E53 BMW X5 3.0i