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Crankshaft Pulleys & Harmonic Balancers

Keep your drive belt system in check by replacing your BMW's crankshaft pulleys and harmonic balancers.
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ATI Performance Products - Corporate Logo
T#:639878
Part#: VAC-HPCDK-S54-ST
In Stock
$ 1,049.99 USD
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$ 1,049.99 USD
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If you are breaking crankshafts and oil pumps, the cause may be a mystery to you as it has been to many of our customers. We know that controlling the harmonic resonance of the BMW 6 is highly important as RPMs rise, but the ideal configuration of the inline-6 motor makes even experienced engine builders overlook some fundamental principals of engine harmonics that can be destructive. ATI Performance Products has partnered with VAC Motorsports to develop new dampers for BMW 2.5L, 2.8L, 3.0L and 3.2L straight-6 engines found in the E36 and E46 M3, E9X and E6X, as well as newer Z3s and Z4s. These dampers eliminate crankshaft harmonic vibration, which allows the engine to produce more horsepower and torque, while also reducing internal engine wear at the same time. Broken oil pumps and timing chains will be a thing of the past! When used with a VAC accessory pulley, these dampers are a direct replacement over the OEM balancer. They have a 7” outer diameter and include OEM style timing alignment tabs. BMW enthusiasts should know that all ATI Super Dampers exceed SFI 18.1 Safety Certification and are approved for competition. The advantages of the ATI SuperDamper include eliminating vibration issues with inline 6 engines equipped with lightweight clutch and flywheel assemblies, reduced bearing, engine accessories, oil pump wear, and compatibility with underdrive pulleys. Made in the USA.
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VAC Motorsports - Corporate Logo
T#:27905092
Part#: VAC-HPCD-M50
Ships in 7 Business Days
$ 799.99 USD
Free Shipping on orders $49 and up

If you're grappling with issues like crankshaft failures and oil pump breakdowns in your BMW 6-cylinder engines, you're not alone. Even seasoned mechanics can overlook the critical aspect of harmonic resonance control in these inline-6 motors, despite their optimal configuration.

Enter ATI Performance Products in collaboration with VAC Motorsports, presenting a solution in the form of new dampers tailored for BMW 2.5L, 2.8L, 3.0L, and 3.2L straight-6 engines found in various models like the E36 and E46 M3, E9X, and E6X, as well as newer Z3s and Z4s. These dampers effectively nullify crankshaft harmonic vibrations, paving the way for enhanced horsepower and torque output, alongside a reduction in internal engine wear. Say goodbye to issues like fractured oil pumps and timing chain mishaps! By pairing these dampers with a VAC accessory pulley, you seamlessly replace the OEM balancer. Featuring a 7” outer diameter and OEM-style timing alignment tabs, these ATI Super Dampers boast SFI 18.1 Safety Certification, ensuring they're competition-ready.

What sets the ATI SuperDamper apart? It's the remedy for vibration woes in inline 6 engines, especially those equipped with lightweight clutch and flywheel setups. Expect diminished wear on bearings, engine accessories, and oil pumps, all while being compatible with underdrive pulleys.

Included in the kit are the damper itself, a lightweight VAC Billet Crankshaft Pulley, along with all necessary mounting and installation hardware. Note that it's not compatible with S50B30 & S50B32 Euro Engines. For street/track vehicles with air conditioning, opting for the Additional A/C Pulley Option is imperative, given that the OE A/C pulley isn't compatible. Rest assured, all required mounting and installation hardware is included, and the entire package is proudly Made in the USA.

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ATI Performance Products - Corporate Logo
T#:639880
Part#: VAC-HPCD-S55
In Stock
$ 989.99 USD
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$ 989.99 USD
Free Shipping
If you are breaking crankshafts and oil pumps, the cause may be a mystery to you as it has been to many of our customers. We know that controlling the harmonic resonance of the BMW 6 is highly important as RPMs rise, but the ideal configuration of the inline-6 motor makes even experienced engine builders overlook some fundamental principals of engine harmonics that can be destructive. ATI Performance Products has partnered with VAC Motorsports to develop new dampers for BMW 2.5L, 2.8L, 3.0L and 3.2L straight-6 engines found in the E36 and E46 M3, E9X and E6X, as well as newer Z3s and Z4s. These dampers eliminate crankshaft harmonic vibration, which allows the engine to produce more horsepower and torque, while also reducing internal engine wear at the same time. Broken oil pumps and timing chains will be a thing of the past! When used with a VAC accessory pulley, these dampers are a direct replacement over the OEM balancer. They have a 7” outer diameter and include OEM style timing alignment tabs. BMW enthusiasts should know that all ATI Super Dampers exceed SFI 18.1 Safety Certification and are approved for competition. The advantages of the ATI SuperDamper include eliminating vibration issues with inline 6 engines equipped with lightweight clutch and flywheel assemblies, reduced bearing, engine accessories, oil pump wear, and compatibility with underdrive pulleys. Includes lightweight VAC Billet Crankshaft Pulley. Made in the USA.
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VAC Motorsports - Corporate Logo
T#:12610319
Part#: VAC-HPCD-S14
Ships in 6 Business Days
$ 699.99 USD
Free Shipping on orders $49 and up
NOTE: Due to space limitations, the design of this damper will overdrive your components (water pump, power steering, and alternator) by approximately 10-13%; we highly recommend using underdrive pulleys in your setup Controlling the harmonic resonance of the BMW S14 engine is highly important as RPMs rise, but the ideal configuration of the 4-cylinder motor makes even the most experienced engine builders overlook some fundamental principles of engine harmonics that can be destructive. Harmonics destroy these motors by causing extensive oil pump and crankshaft damage, but the addition of VAC’s Harmonic Damper eliminates the unstable crankshaft harmonic vibrations that cause internal engine wear. By eliminating harmonic vibrations, your S14 engine will be able to produce more horsepower and torque with increased reliability. The VAC/ATI Harmonic Damper is made with an integral pulley, eliminating the need for the additional pulley other models require. Exceeds SFI 18.1 Safety Certification Eliminates problems with lightweight clutch and flywheel assemblies Controls destructive harmonic forces Reduces instances of bearing wear, accessory failure and oil pump failure Includes lightweight VAC Billet Crankshaft Pulley Made in USA ATI Performance Products, Inc. is located in Baltimore, MD, and specializes in producing and maintaining high performance products for street and track applications. Over the years ATI has earned a reputation for its cutting edge technology, attention to detail and rigorous testing under race conditions.
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ATI Performance Products - Corporate Logo
T#:639879
Part#: VAC-HPCD-N54
In Stock
$ 1,059.99 USD
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$ 1,059.99 USD
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If you are breaking crankshafts and oil pumps, the cause may be a mystery to you as it has been to many of our customers. We know that controlling the harmonic resonance of the BMW 6 is highly important as RPMs rise, but the ideal configuration of the inline-6 motor makes even experienced engine builders overlook some fundamental principals of engine harmonics that can be destructive. ATI Performance Products has partnered with VAC Motorsports to develop new dampers for BMW 2.5L, 2.8L, 3.0L and 3.2L straight-6 engines found in the E36 and E46 M3, E9X and E6X, as well as newer Z3s and Z4s. These dampers eliminate crankshaft harmonic vibration, which allows the engine to produce more horsepower and torque, while also reducing internal engine wear at the same time. Broken oil pumps and timing chains will be a thing of the past! When used with a VAC accessory pulley, these dampers are a direct replacement over the OEM balancer. They have a 7” outer diameter and include OEM style timing alignment tabs. BMW enthusiasts should know that all ATI Super Dampers exceed SFI 18.1 Safety Certification and are approved for competition. The advantages of the ATI SuperDamper include eliminating vibration issues with inline 6 engines equipped with lightweight clutch and flywheel assemblies, reduced bearing, engine accessories, oil pump wear, and compatibility with underdrive pulleys. Includes lightweight VAC Billet Crankshaft Pulley.
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ATI Performance Products - Corporate Logo
T#:22756711
Part#: 917992
In Stock
$ 370.99 USD
Free Shipping on orders $49 and up

The ATI Super Damper, meticulously designed for late-model 1.6L Mini Cooper engines, stands as the top choice and a rarity with its SFI 18.1 Certification, ensuring optimum performance for your MINI Cooper.

Key Features:

  • Compatible with 2001-2006 Mini Cooper and Mini Cooper S models.
  • Effectively dampens torsional crankshaft vibrations across all RPM levels.
  • Provides protection against engine harmonics.
  • A direct replacement for the OEM unit, ensuring ease of installation.
  • Equipped with a 6-rib serpentine belt drive for reliable performance.
  • Laser-etched timing marks for precision.
  • SFI 18.1 Certified for competition use, meeting rigorous standards.
  • Note: A belt tensioner tool is required to remove or replace the factory belt, and the ATI puller is not compatible with this damper.

Specifications:

  • Shell Material: Aluminum, 6-rib
  • Hub Material: Steel 916102
  • Inertia Weight: 2.20 lbs, 3 ring
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Alta Performance - Corporate Logo
T#:26238480
Part#: AMPENG520
In Stock at Vendor
$ 129.99 USD
Free Shipping on orders $49 and up

Enhance the performance of your Mini with the ALTA Lightened Crank Pulley (LCP), engineered to increase horsepower and torque. Available in 0% Stock Sized and +2% Oversized options, this pulley is crafted from 6061T6 aluminum, weighing only 0.65 lbs. Significantly lighter than the stock crank pulley, the ALTA LCP ensures improved engine efficiency without adding vibration or noise. The +2% Oversized pulley provides additional boost for Supercharged Cooper S models, delivering safe and reliable performance. With increased belt contact, this pulley reduces wear and enhances durability, making it a must-have upgrade for Mini enthusiasts.

  • Increases horsepower and torque
  • Lightweight 6061T6 aluminum construction
  • Available in 0% Stock Sized and +2% Oversized options
  • Does not affect charging system
  • Improves engine efficiency and performance
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Alta Performance - Corporate Logo
T#:394899
Part#: AMPENG500
In Stock
$ 129.99 USD
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$ 129.99 USD
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ALTA Lightweight Crank Pulley (LCP) for Mini

Upgrade your Mini's performance with the ALTA Lightweight Crank Pulley (LCP), designed to increase horsepower and torque. Available in two sizes - 0% Stock Sized and +2% Oversized - this pulley is engineered for Supercharged Cooper S models. Crafted from 6061T6 aluminum, the ALTA pulley is lightweight, weighing just 0.65 lbs, providing a weight reduction of over 2.3 lbs compared to the stock crank pulley.

  • Increases horsepower and torque
  • Lightweight design reduces rotational mass
  • Does not wear out engine bearings or oil pump
  • Adds boost safely and reliably
  • Improves belt contact with pulleys, reducing wear
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Crank Pulley With Dampener
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:38587673
Part#: 11237829906
Ships in 3 Business Days
$ 89.99 USD
Free Shipping on orders $49 and up
ATI Performance Products - Corporate Logo
T#:22756691
Part#: 917993
In Stock
$ 370.99 USD
Free Shipping on orders $49 and up

ATI Super Damper for Enhanced MINI Cooper Performance

Upgrade your MINI Cooper with the ATI Super Damper, a top-rated and SFI 18.1 Certified replacement. Designed to fit 2001-2006 Mini Cooper and Mini Cooper S models, this damper is engineered to dampen torsional crankshaft vibrations across all RPM levels, ensuring smooth and reliable performance. It serves as a vital shield against engine harmonics and is a direct replacement for the OEM unit. The 6-rib serpentine belt drive and laser-etched timing marks offer precision and accuracy. Please note that a belt tensioner tool is necessary for removing or replacing the factory belt, and the ATI puller is not compatible with this damper.

Key Features:

  • SFI 18.1 Certified for competition use
  • Provides effective torsional crankshaft vibration damping
  • Direct replacement for the OEM unit
  • 6-rib serpentine belt drive
  • Laser-etched timing marks for precision

Specifications:

  • Shell Material: Aluminum, 6-rib
  • Hub Material: Steel 916102
  • Inertia Weight: 2.20 lbs, 3 ring
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ATI Performance Products - Corporate Logo
T#:7355606
Part#: HPCDK-S50B32-S
Ships in 3 Business Days
$ 1,099.99 USD
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$ 1,099.99 USD
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ATI Performance Products - Corporate Logo
T#:27605443
Part#: ATI-HPCD-B58
Ships on Sep 1, 2026
$ 389.99 USD
Free Shipping on orders $49 and up

Understanding the criticality of harmonic resonance in BMW inline-6 engines, ATI Performance Products has collaborated with VAC Motorsports to craft revolutionary dampers. Designed for BMW 2.5L, 2.8L, 3.0L, and 3.2L straight-6 engines in E36 and E46 M3, E9X, E6X, Z3s, and Z4s, these dampers tackle harmonic vibrations, unlocking heightened horsepower, torque, and longevity. Forget about broken oil pumps and timing chains!

Pairing seamlessly with VAC accessory pulleys, these 7" diameter dampers boast OEM-style timing alignment tabs, ensuring a direct fit over OEM balancers. Notably, all ATI Super Dampers exceed SFI 18.1 Safety Certification for competitive use, making them a must-have for BMW enthusiasts. Benefits extend to eliminating vibration issues with lightweight clutch and flywheel assemblies, reducing wear on bearings, engine accessories, and oil pumps, and harmonizing with underdrive pulleys.

Plus, each package includes the lightweight VAC Billet Crankshaft Pulley, proudly made in the USA for uncompromised quality assurance.

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ATI Performance Products - Corporate Logo
T#:639877
Part#: VAC-HPCD-M50-TR
Ships on Sep 1, 2026
$ 1,139.99 USD
Free Shipping
$ 1,139.99 USD
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If you are breaking crankshafts and oil pumps, the cause may be a mystery to you as it has been to many of our customers. We know that controlling the harmonic resonance of the BMW 6 is highly important as RPMs rise, but the ideal configuration of the inline-6 motor makes even experienced engine builders overlook some fundamental principals of engine harmonics that can be destructive. ATI Performance Products has partnered with VAC Motorsports to develop new dampers for BMW 2.5L, 2.8L, 3.0L and 3.2L straight-6 engines found in the E36 and E46 M3 as well as newer Z3s and Z4s. These dampers eliminate crankshaft harmonic vibration, which allows the engine to produce more horsepower and torque, while also reducing internal engine wear at the same time. Broken oil pumps and timing chains will be a thing of the past! When used with a VAC accessory pulley, these dampers are a direct replacement over the OEM balancer. They have a 7” outer diameter and include OEM style timing alignment tabs. BMW enthusiasts should know that all ATI Super Dampers exceed SFI 18.1 Safety Certification and are approved for competition. The advantages of the ATI SuperDamper include eliminating vibration issues with inline 6 engines equipped with lightweight clutch and flywheel assemblies, reduced bearing, engine accessories, oil pump wear, and compatibility with underdrive pulleys. Kit includes: Damper Lightweight VAC Billet Crankshaft Pulley Mounting and Installation Hardware Trigger Ring for OBD1 systems Note: Will NOT work with S50B30 & S50B32 Euro Engines, For Street/Track cars with Air Conditioning, the Additional A/C Pulley Option is REQUIRED as the OE A/C pulley is not compatible. The additional mounting and installation hardware is also included. Made in the USA
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M7 Speed - Corporate Logo
T#:584439
Part#: 53-3M7101-4
In Stock
$ 159.99 USD
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$ 159.99 USD
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M7 Speed 4% Oversize Crankshaft Pulley for MINI Cooper

Unlocking Performance

The M7 Speed 4% oversize crankshaft pulley is your ticket to unlocking the hidden potential of your MINI Cooper. This performance-enhancing pulley is designed to add power, acceleration, and overall performance to your beloved MINI. Here's how it does the trick:

Performance Boost:

  • Safely speeds up your supercharger, delivering a significant "low end" boost and torque.
  • The result? Your MINI Cooper takes off with newfound energy and responsiveness.

Lightweight Advantage:

  • Weighing just 13 ounces, this pulley is a remarkable 88.5% lighter than the factory version.
  • Reduced crankshaft rotational mass equals more horsepower, torque, and improved throttle response.

Advanced Design

The M7 Speed 4% Crank Pulley isn't just about performance; it's also a work of art. Crafted with advanced computer modeling and precision CNC machining, it's a blend of form and function:

Materials:

  • Made in the USA from billet 6061-T6 aerospace-grade aluminum alloy.
  • Features a deep black anodized coating and laser etching for a sleek look.

Precision Machining:

  • Micro V-Belt grooves meet SAE J1459 specifications to minimize belt slippage, especially at maximum boost.

Optimal Fit:

Use it in conjunction with the M7 Speed 16% Supercharger Technology Pulley for peak performance in MINI tuning.

Reliable Performance

From the factory, MINI lacks a positive drive key on the crankshaft snout to drive the lower pulley. Most aftermarket pulleys are slip-fit and rely on the bolt to prevent slippage. The M7 Speed crank pulley is engineered differently:

Interference Fit:

The pulley is interference-fit onto the crankshaft, ensuring zero slippage even at high RPMs.

Features at a Glance:

  • Super Lightweight: Only 13 ounces (0.3 kg)
  • Sheds 6.2 lbs (2.8 kg) compared to stock
  • Achieves perfect balance through a symmetric design and precision machining
  • Includes a high-quality ARP Racing bolt and precision ground flat washer
  • Installation is a breeze

Unleash Your MINI's Potential

Proudly made in the USA, the M7 Speed 4% Oversize Crankshaft Pulley is the upgrade your MINI Cooper deserves. Unleash its hidden power and enjoy a new level of performance, reliability, and overall driving pleasure. Get ready to experience the difference.

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Vibration Damper
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:38161721
Part#: 11237513862
Ships in 3 Business Days
$ 92.99 USD
Free Shipping on orders $49 and up
Adjustment Pulley W11 1.6L Engine
We Price Match - Give Us A Call or Chat!
Ina - Corporate Logo
T#:591703
Part#: 11288625983
In Stock
$ 31.99

This product was last offered at the strikethrough price on
08-12-2026

$ 28.99 USD
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$ 28.99 USD
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Ensure your Mini's engine runs smoothly with the idler pulley, a crucial component in routing the serpentine belt. Discover the benefits below:

  • Smooth Belt Routing: Helps to effectively route the serpentine belt for optimal engine performance.
  • Prevents Rattles: Eliminates high-pitched rattles caused by worn-out bearings, ensuring a quieter driving experience.
  • Easy Installation: Simple bolt-on design requires no special tools, making installation hassle-free.
  • Enhanced Engine Performance: Maintains proper belt tension, preventing slippage and ensuring efficient power delivery.
  • Durable Construction: Crafted from high-quality materials for long-lasting durability and reliability.

Upgrade your Mini's engine with the idler pulley to maintain smooth belt operation and prevent unwanted noises.

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Bavarian Autosport - Corporate Logo
T#:19792190
Part#: 11211439395
In Stock
Sale - Save 20% $ 18.99

This product was last offered at the strikethrough price on
05-03-2026

$ 15.19 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 18.99

This product was last offered at the strikethrough price on
05-03-2026

$ 15.19 USD
Free Shipping on orders $49 and up
Replacement center bolt for the engine crank pulley.
Bavarian Autosport - Corporate Logo
T#:16940487
Part#: 11217616164
In Stock
Sale - Save 23% $ 12.99

This product was last offered at the strikethrough price on
05-03-2026

$ 9.99 USD
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Sale - Save 23%
$ 12.99

This product was last offered at the strikethrough price on
05-03-2026

$ 9.99 USD
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Used to attach the crank pulley / vibration dampener

Vibration Damper
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:38195378
Part#: 11231438995
Ships in 3 Business Days
$ 112.99 USD
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Crank Pulley With Dampener
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:599037
Part#: 11237638551
Back Ordered
$ 87.99 USD
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$ 87.99 USD
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Bremmen Parts - Corporate Logo
T#:48780737
Part#: 11288625983
Ships in 8 Business Days
Sale - Save 7% $ 25.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.22 USD
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Sale - Save 7%
$ 25.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.22 USD
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Genuine BMW Motorsport - Corporate Logo
T#:396369
Part#: 12311311449KT
Ships on Sep 17, 2026
$ 1,696.99 USD
Free Shipping on orders $49 and up

Group A racecars were the top of their class in both touring car and rally racing. Heavily modified and extremely fast these cars set out to demonstrate the best of what a manufacturer could do on the racetrack. It was the predecessor to the current DTM class racing and set a standard for many other divisions of motorsport to follow.  

One of the weaker points of the S14 engine, when speaking from a racing standpoint is the belt drive system. While fine for a street going car, a V-belt is not suitable for high RPM applications. On the track, most of your time will be spent in the higher rev range which puts extreme amounts of stress on the factory setup. BMW realised this and came up with a solution that involved doing away with the V belt system and using a 6 rib serpentine style instead.

Extremely resistant to slippage and failure this design holds up much better the abuse of track duty and won't leave you stranded and waiting for tow back to the pit. Additionally, this kit does not accommodate and a/c compressor and the alternator and waterpump are underdriven by way of slightly larger pulleys. Combined, this puts less of a load on the crankshaft which leads to more efficient power delivery to the ground. If you track you E30 M3, this is an essential upgrade and until now was extremely difficult to source. Do not skip this pivotal step in your engine build or overhaul and get a leg up on the competition the Group A way.
Please note this kit is special order and in non-returnable

Features:

  • Kit replaces all engine pulleys and crank damper
  • Includes 6 rib serpentine belt
  • Underdriven waterpump and alternator pulleys
  • Recommended for off road and racing use only 

This kit fits the following BMWs:
1986-1992 BMW M3 All 
 

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Bremmen Parts - Corporate Logo
T#:28138093
Part#: 11237638551
Special Order: No Guaranteed ETA
Sale - Save 11% $ 72.99

This product was last offered at the strikethrough price on
05-03-2026

$ 65.17 USD
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Sale - Save 11%
$ 72.99

This product was last offered at the strikethrough price on
05-03-2026

$ 65.17 USD
Free Shipping on orders $49 and up

MINI Crank Pulley With Dampener - R5X R6X

Improve engine performance and reduce vibrations with the MINI Crank Pulley With Dampener - R5X R6X. This pulley-driven unit is designed to smooth out rotational vibrations from the crankshaft, ensuring smoother engine operation. When the pulley wears out or dries out, you may notice unusual noises near the passenger's side oil pan, indicating the need for replacement.

Benefits:

  • Reduces rotational vibrations for smoother engine operation
  • Minimizes noise from the passenger's side oil pan
  • Enhances overall engine performance

For optimal results, it's recommended to replace the hex bolts along with the crank pulley.

Upgrade your MINI's engine performance and reduce vibrations with the MINI Crank Pulley With Dampener - R5X R6X.

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ATI - Corporate Logo
T#:43142744
Part#: 918351
Back Ordered
$ 418.99 USD
Free Shipping on orders $49 and up
This ATI Super Damper is a direct replacement for the OEM Harmonic Balancer, designed to further reduce harmful engine harmonics that could lead to damage to sensitive engine components. The 21% underdrive function of this super damper is designed to greatly increase usable horsepower for racing applications by driving engine accessories slower, reducing overall parasitic power loss.
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ATI - Corporate Logo
T#:43142743
Part#: 918352
Back Ordered
$ 451.99 USD
Free Shipping on orders $49 and up
This ATI Super Damper is a direct replacement for the OEM Harmonic Balancer, designed to further reduce harmful engine harmonics that could lead to damage to sensitive engine components. The 10% underdrive function of this super damper is designed to increase usable horsepower by reducing parasitic power loss without greatly affecting engine accessories.
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