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SR Performance Underdrive Pulleys (05-10 GT)

Market Price $186.99 You Save 12% ($22.04)
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$164.95

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  • Item 41131
  • MPN# 41131

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    Features, Video & Details

    • Free Up Horsepower
    • Complete Kit
    • Durable, Lightweight Aluminum
    • Brilliant Polished Finish
    • Premium Quality
    • Fits 2005-2010 GT and Bullitt Mustangs

    Review & Installation Video

    Review & Install Video

    Hey I’m Justin with AmericanMuscle.com, and I’m breaking down these underdrive pulleys from SR Performance, fitting the 4.6L V8 motor found in all 2005-2010 Mustang GTs. Engine accessories like the AC compressor, water pump and alternator can really rob your car of horsepower, a great example of how much power an accessory can eat up is whenever you turn your cars AC on and instantly it feels a little more sluggish. This is referred to as parasitic drag. The idea of an underdrive pulley is to turn the different accessory pulleys at a different speed, using these different sized pulleys thus requiring less power from the motor to drive each accessory. This reduction in drag on the crank shaft should allow the motor to operate more efficiently, and essentially equate to more power at the rear wheels. The SR Performance kit includes a new water pump pulley along with a brand new crank pulley, and the hardware needed for the install. Both pulleys are SF5 certified and are constructed using lightweight aluminum. As an added bonus, that bright polished finish is sure to look good under the hood as well. As far as the install is concerned, you just want to leave yourself a couple of hours to get both pulleys installed. Ideally, you should have a torque wrench on hand as well as some high temp RTV sealant and a breaker bar for that crank pulley bolt. This isn’t the hardest job in the world, but if you’ve never attempted it before, I really suggest watching the detailed instruction video located on this product page before getting started on the install. So be sure to check out the SR Performance underdrive pulleys right here at AmericanMuscle.com

    Untap Hidden Horsepower. Don't let your accessories and A/C drain power from your GT or Bullitt Mustang. By replacing your factory pulleys with this SR Performance Underdrive Pulley Kit, you'll free up to 15 horsepower that's currently being drained by your accessories and put it back where it belongs - under your right foot. Best of all, you won't affect your vehicle's charging or cooling capacity in the process.

    SFI Certified Design. If you're ready to take it to a track, you'll rest easy knowing these SR Performance Pulleys are SFI Certified.

    Premium Quality. Don't settle for inferior parts. These premium quality SR Performance Pulleys are made from lightweight aluminum for durability and performance. Made using precise, state-of-the-art CNC manufacturing, you can count on these pulleys to perform at the highest level.

    Easy Installation. This SR Performance Mustang Underdrive Pulley Kit installs quickly and easily in under 2 hours with no modifications required.

    Application. These SR Performance Underdrive Pulleys are specifically designed for use on the 2005 to 2010 GT and 2008 to 2009 Bullitt Mustangs.

    Fitment: 2005 2006 2007 2008 2009 2010 Details

    What's in the Box
    • (1) Crank Pulley
    • (1) Water Pump Pulley
    • (1) Crank Bolt
    • (1) Instruction Sheet
    Installation Info
    Tech Specs
    Underdrive Pulley Specifications
    Year/Model: 2005-2010 GT Manufacturer: SR Performance
    Material: Aluminum Finish: Polished
    Crank Pulley: One Piece Crank SFI Certified: Yes
    Will it fit my Mustang?

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    19 Questions / 6 Answers

    Ask a Question

    Low accessories power? How much power will this take away from the accessories? Is it a noticable difference or not?

    Josh08

    • I had the same worries, but after the install I checked the output voltage on the alternator and all around the vehicle before and after the installation and there was no power shortage at all, and for the performance the pony revs way more faster......and it looks cool.....

      Rafael

    Show 2 more answers Helpful (7)

    can i use this for the Mustang 2006 V6??

    Jose

    • These pulleys will not work for the 2006 V6 Mustangs.

      KevinD92

    Helpful (1)

    Work with on a V6? I've seen on a few forums people were saying to increase HP on a V6 to get an underdrive pulley, but the only ones on here are for GT's. Was just wondering if these would work on a V6.

    ZStang07

    • I would only get pulleys that are meant for your specific engine. Could cause problems otherwise and I doubt they'd fit.

      MarkL

    Helpful (1)

    is this considered a non piggyback ?

    ChrisB

    • The SR Performance Underdrive Pulleys will replace your OEM balancer and crank pulley, and will not piggy back off of the stock balancer.

      AMRobD

    Helpful (0)

    I've had mine in a box for about 2 yrs now. My concerns relative to mostly what I've read online. I'm 52 yrs young, so aftermarket isn't anything new to me. My situation is, our 09GT 5spd is a daily driver for my wife, thankfully she works 2 miles away from home. However, with the changes, both Pro and Con, these pulleys make I see/read the effects with the alternator, but whats the deal with the A/C? We live in FL. so anyone married knows what life is like without A/C in the wife's car.

    HotRod

    Will this work with a 150 shot of nitrous set up?

    JosrC

    People Who Bought This Item Also Bought

    Customer Reviews (94) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:0-$100

    • Performance Gain 4.356322 4.4
    • Fit 4.852273 4.9



    • 5/5

      May 19, 2018

      Worth the price

      Nothing too noticeable, but the difference is still there. You can tell it does something.

      LeviM

      Year: 2005 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Afternoon

      April 29, 2018

      SR UDP

      Product has a great finish.....the pulleys also work great .....in my opinion the only reason not to install udp is a s/c

      Moe

      Year: 2005 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      April 09, 2018

      Worth it

      Minus not being supplied an alternator bolt and having to grind down the stock alternator bolt, this is a pretty good kit, installation instructions are straight forward and with the right tools, install is a breeze. Noticeable gains in the mid power and range.

      Easy

      Year: 2006 Submodel: GT

      Helpful (2)

    • 4/5

      March 08, 2018

      great quality

      Have not installed yet, to cold out, lol but the quality of the pulleys looks great, instuctions are included and arfe very easy to follow

      jasons

      Year: 2006 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      March 05, 2018

      Great Buy

      Fast shipping from AM! Install took me and a buddy about 3-4 hours with every tool needed from instructions. Looks clean in the engine bay and noticed a slight increase in the lower rpms as well as a deeper exhaust note (quite surprised). Most importantly I do not feel that drain the AC takes anymore and car runs a lot smoother.

      EBoss

      Year: 2010 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      March 03, 2018

      Pullllls

      Worth every penny req retune if your mustang been tune gain 35hp 13 trq

      JacoryC

      Year: 2010 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      February 16, 2018

      Big difference

      Looks great. Definitely can tell a difference. Love it! Lil modding had to be done. Looks good with an add on mod. Moroso coolant tank!

      Jd

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      January 03, 2018

      Underdrive pulley

      Easy to install and could tell a difference in power

      GarretR

      Year: 2008 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      December 10, 2017

      Add a little more

      Great fit, easy install. I have read bad reviews about not charging the battery proper or a/c now working properly. I have had NO issues with this.

      JeffC

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      October 31, 2017

      Definitely a must have or at least

      After my local shop finished installing these pulleys. It definitely looks better than the stock pulleyes and I notice a difference in when I put it in drive. Because when I had the stock ones I had to put my foot on the gas a little bit to make go but now it just wants to go!

      AdamR

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      October 21, 2017

      Cool beans!!

      Not a bad purchase. Could tell the difference from before.

      JuanC

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      October 11, 2017

      SR Pulleys

      Great Price, Great Quality, and I felt some power gains!

      RubenC

      Year: 2010 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      September 07, 2017

      Amazing

      Install was about an hour and the difference is noticeable especially at the track don't let the brand fool you they work as good as any other.

      PhatboiStang562

      Year: 2006 Submodel: GT

      Helpful (1)

    • 4/5

      Installation Time: Afternoon

      September 01, 2017

      Bang for your buck!!

      Install was easy.Can feel a difference in power band just as good as higher priced ones. Could have coated the the crank pulley.

      JFuller

      Year: 2008 Submodel: GT

      Helpful (1)

    • 3/5

      Installation Time: Less than 1 Hour

      August 16, 2017

      Budget pulley

      Quick and easy install. Looks great.just make sure to completly seal the key way to prevent oil seepage.

      MiltonM

      Year: 2005 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      July 31, 2017

      Great parts

      Pulleys were excellent quality. Super easy install loved them.

      LeviA

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      July 22, 2017

      Inexpensive easy bump for HP and MPH

      Took a morning to install pulleys but did buy the recommended replacement bolt (rather than cut off) before starting and had it changed over in a few hours. Instantly noticed a little extra go and next tank picked up 1.5 MPG. I was amazed! I drive mainly on the freeway so AC and charging, no problem. Do notice a little drop in AC performance if stuck in traffic or city driving but I'd expect that. Overall, well worth the $$$$

      JimB

      Year: 2009 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      July 21, 2017

      SR underdrive pulleys

      Look great easy install. Slight performance gain overall pleased with them.

      Gene

      Year: 2007 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      July 19, 2017

      Very nice

      My 2008 mustang runs great with the new pulleys, you can feel the difference big time. Good price, easy install.

      JasonB

      Year: 2008 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      July 19, 2017

      Great Quality

      This product was easy to install and quality material. I can't say if it had performance gain because I did so much work to the motor at once.

      KyleK

      Year: 2007 Submodel: GT

      Helpful (1)

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