MPx Lightweight Underdrive Pulley Kit, 2012+ Fiat 500 Abarth / 2013-16 Dart 1.4L/Renegade 1.4L

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Model Number: 226126-KIT

Would you like to pick up another 6-8 HP and additional torque at the wheels in your 2012+ Fiat 500 Turbo / 2013+ Dart 1.4L and Renegade 1.4 Turbo.

Would you like to have an improved throttle response, and a LOT more fun driving your 1.4L turbo engine Fiat / Dart / Renegade?

If so, this is a great bolt on item for you!

We were the very first company to make a lightweight pulley for the 1.4 turbo engine. We've also tested nearly 7 different size/weight prototypes to make sure we have the absolute perfect pulley kit for you!

Here are the facts:

  • The stock pulley weighs in at 3.35 lbs, and the MPx lightweight underdrive pulley weighs in at 1.8 lbs. Saving nearly 1.6 lbs of sprung mass off of the crankshaft allows for a quicker revving engine, and less power loss spinning dead weight!
  • We were able to underdrive the accesories by 20% without affecting the AC and alternator.
    This means less power is robbed from the crankshaft for the ac and alternator, but both still function fine. We are still getting good cold ac, and a good charge from the alternator, and again, no check engine lights.
  • We gained solid horsepower and torque across the entire rpm range, not just power up top, or on bottom! This will make a difference you can feel.
  • This pulley kit is consists of an outer billet pulley, tone wheel, longer crank pulley bolts, and a Gates belt. When changing the pulleys out, the 1.4L has an allignment guide pin with offset mounting holes that will make it impossible to install incorrectly. Installation is not difficult and any good mechanic, or home mechanic should be able to install this in under an hour with basic hand tools all from within the passenger side wheel well.
  • This kit is all American made. We have an outer aluminum pulley thats hard anodized for long life and great looks, and a trigger wheel thats made out of steel and is zinc coated. We also provide a brand new Gates belt and three bolts in this kit for you.
  • We have been machining crankshaft pulleys since 2000, and have tons of experience with them. This means that we know what is necessary for correct hard coatings for long term use, and whats necessary for no check engine lights, etc.

An illustrated install guide is included with each kit.

If you already have this pulley kit and need a new belt, here is the belt part number: (Fiat 500 1.4 Turbo and Dart) 5050480, (500L): Dayco 5050459. Your local auto parts store can cross reference this to whatever belt they offer locally.

MPx Lightweight Underdrive Pulley Kit, 2012+ Fiat 500 Abarth / 2013-16 Dart 1.4L/Renegade 1.4L, Engine: Store Name

Ask a Product Question

  • Henry
    How much horsepower does this bolt on add to the car?
    1 Answer
    • customer service rep

      1.4 Turbo Fiats and Dodge Darts will gain anywhere from 5 hp to 7 hp peak at the wheels depending on other mods. Plus, you'll gain throttle response which will make your car a lot more fun to drive!
  • tom 500 spot
    Is there any reason this would not work on a non-turbo fiat 1.4L?
    1 Answer
    • customer service rep

      This pulley does not work with the non turbo 1.4 as the non turbo 1.4 uses a different crank pulley than the turbo models. We do offer a non turbo 1.4 pulley though, use the search bar and use this part number: 226126-NA
  • Dave
    Are there installation instructions available for review?
    How long does it take to install?
    1 Answer
    • customer service rep

      Installation by a good mechanic would take about 20-30 minutes. We can send you a copy of the installation instructions, please email us and we can email you instructions back. Our email address is
  • jason
    Is this pulley balanced with dampers like the factory one?
    1 Answer
    • customer service rep

      This pulley kit is made from billet aluminum on a precision CNC machine. It is balanced and will not cause any issues with the motor. As of 6/18/2015 our prototype pulley kit has been on our test car for nearly 20,000 miles and is working great. We've also shipped many, many of these kits and not had any issues whatsoever.
  • John
    Does this change the belt size? will a OEM belt fit with this pulley kit?
    1 Answer
    • customer service rep

      The belt size is different due to the underdrive, and therefore, thats why we include a new belt with the pulley.
  • Brandon
    Wasn't this for all 3 engines? Why id it only for the 1.4 darts now?
    1 Answer
    • customer service rep

      This pulley only works on the 1.4 turbo. We have a pulley kit for the Dart with 2.0 and 2.4 engines (part number 223126). We also have a Fiat 1.4 non turbo lightweight underdrive pulley as well (part number 226126-NA) .
  • Daryl
    Since the OEM belt will no longer work with this pulley, do you offer replacement belts for this kit? Just thinking long term maintenance.
    1 Answer
    • customer service rep

      The belt number is 5050480. This is a Dayco belt, but your local auto parts store can easily cross reference this belt to whatever brand they have in stock.
  • nakai stevens
    On other lightweight pulleys ive noticed the hole for the alignment pin. i havent seen any kind of sign that your version has the same hole, just a little curious as to why before i make a purchase especially since yours is the lightest on the market.
    1 Answer
    • Customer Service Rep

      The pin goes through the trigger/timing wheel, but not the pulley. Its not necessary to have the pin go through the pulley as it doesn't need to be aligned perfectly like the trigger wheel. But also, the three bolts that secure the pulley/trigger wheel together and to the crank prevent any movement whatsoever.
  • Alex May
    Will it fit my 2013 Abarth 595 Turismo T-jet (european model) ?
    1 Answer
    • Customer Service Rep

      Most of the engine mods we have (throttle body, pulley, etc) are not compatible with the European model of 500.
  • Hiram
    can I apply this part without having to change out my clutch?
    1 Answer
    • Customer Service Rep

      This part has nothing to do with the clutch. The clutch is inside the transmission on the driver side of the car, and this pulley goes on the end of the crankshaft on the passenger side of the car.
  • Chris
    What are the bolt specs? Size and length?
    1 Answer
    • Customer Service Rep

      There are three bolts, and they are M8x30mm.