MPx Underdrive Pulley, 03-05 Neon SRT-4 / 01-10 PT Cruiser

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Model Number: 221118-SRT4KIT

Introducing the new Version 3 MPx Underdrive Pulley for the 03-05 Neon SRT-4 & 01-10 PT Cruiser. This pulley is yet another redesign of the famous MPx pulley that has been out for the since 2003.

This underdrive pulley creates more power over the stock pulley by reducing overall weight, and size of the crank pulley. This allows your car to rev faster, and overall be much more peppy.

We provide installation instructions, as well as new belts for your power steering/ac, and alternator, so its a complete installation package! You need nothing else to install this other than your tools! (PS/AC belt 5040525, Alt 5040315)

Dustin H that owns a 2005 PT Cruiser 2.4 non turbo told us that he is using this pulley with AC delete kit and he is using belt number K040490 for the ps/AC belt.

Option

$119.99

MPx Underdrive Pulley, 03-05 Neon SRT-4 / 01-10 PT Cruiser, Accessory Drive: Store Name

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  This is not to answer questions about your orders, or problems you are having with a part you ordered. If you have questions about a part you have already ordered, please contact us by email at info@modernperformance.com or call us 713-270-8520 for faster service.
cisco

Does the timing have to be done when u replace this?

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  No, this has nothing to do with timing, or the timing components. This is the pulley, and drive belts that drive the alternator, power steering and AC.
Deonte

This good for stock motor, or has to be a built motor?

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- customer service rep
  
  Perfect for stock motor, or for anyone looking to improve their throttle response and power.
- customer service rep
  
  This pulley kit works fine on SRT4 motors, it does not need to be a built motor.
Anonymous

Im running the power steering and the ac delete kit. what belt size do i need. 5040525 is to big

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- customer service rep
  
  We do not have measurements of what belt size you would need. Please use a measuring tape, run around the crank pulley, and your power steering pulley to get a measurement, and get the corresponding belt from your local auto parts store.
Brandon

Are these pulleys balanced?

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- customer service rep
  
  These pulleys are precision made with billet virgin aluminum on a cnc machine, and they are perfectly balanced. This is not a rough cast part that needs balancing afterwards.
Julio

How much HP do you think this frees up to the wheels?

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- customer service rep
  
  This will give a 7-8+ hp gain, and faster revving/acceleration.
Rob Baumgartner

I have a pt cruiser gt. Will I have any over heating issues after installing.

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  This pulley drives the alternator and the power steering/air conditioning. It has nothing to do with coolant, or the water pump as that is driven by the timing belt. So, in summary, there is zero affect on cooling after installing this.
Eddie

Would this use the same belt as oem? Also, Would I have any issues with this part since I have a built motor with the balance shaft removed?

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  This pulley kit uses belts smaller than the factory belts because the pulley is undersized. This pulley can be used on motors with and without balance shafts, no problem.
Andrew Moen

Can some one tell me the belt length I need it I have this under drive pulleY the AC delete pulley i bought this from you guys and the AC delete kit both with Belts and none of the supplied belts fit

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  Sorry, as of 6/27/18 we do not have the MPx underdrive pulley and AC delete combination belt size. You'd need to measure the circumference of the belt needed around the crank pulley, power steering pump and ac delete pulley with a piece of string, and then go into your local auto parts store to reference the built you need.
Alfredo Vera

Will this work with the A.c. Delete kit ?

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  Yes, you can use a underdrive pulley with a AC delete kit, however, we do not currently have the belt size that you'll need. So, you'd need to install the crank pulley and then measure around the crank pulley, around the tensioner and power steering pulley with a measuring tape, and then go to a local auto parts store to buy the belt. We recommend buying three belts, one larger, one smaller, and the one size you need. Then return the ones you dont use.
johannes grondelle

In regard to mpx new under drive pulley , using a flexible tape will give you the belt length in mm , most belt part numbers have this as the last digits: number of ribs on pulley at start , eg . 4x , 6x . I hope this helps out some of you guys. Cheers from Australia.

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  Correct, you can measure the diameter around the pulleys to get the length of belt you need and go to the local auto parts store to get a belt to match what you need.
Darryl

What pulley puller would I use to remove mpx under drive pulley thanks

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  Its best to use a pulley puller with three bolts that can be threaded into the pulley for removal.
andres

is this crank pulley safe to use on a built motor with big cams and solid mounts? (more engine vibrations)

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  We only recommend using this pulley on SRT-4's and Turbo PT Cruisers with less than 300 horsepower. This is because highly modified SRT-4's can have detonation, and we recommend keeping the stock pulley over 300hp to absorb and counter the detonation. 2.4 Turbo engines over 500HP need even further dampening, and that is why we recommend using the ATI damper with high horsepower builds.