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SR Performance Underdrive Pulleys; Polished (86-93 5.0L Mustang)

Item 525568
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      Video Review & Installation

      Hey guys, Adam here with Today I'm bringing you a detailed overview and installation of the SR Performance Polished Underdrive Pulleys, fitting all '86 to '93 5 liter Mustangs. In this video I'll be going over exactly how underdrive pulleys work and what they are in regards to the benefits to your engine. I'll talk about the materials and construction, and I'll top the video off with the installation, which I'll let you know upfront here, underdrive pulleys are a very simple bolt-on mod, something that will get a one outta three wrenches on our difficulty meter. The SR Performance Underdrive Pulleys in the polished finish we have here today will be for any '86 to '93 5 liter Mustang owner who might be looking to free up some of the energy that the engine is using to power the factory pulleys in order to free up horsepower that can be used in other performance mods. Now on top of that, the installation is extremely simple, it's a very simple bolt-on mod here that we'll talk about a little later in the video, but upfront this is something that just allows you to pick up some horsepower in other areas instead of using that power for the factory pulleys. So the first thing I wanna touch on exactly is what are underdrive pulleys, what do they do, and what benefits do thy have for your engine. Now in a nutshell, underdrive pulleys basically cut down on parasitic drive train lost by reducing the amount of power it takes to run your accessories like the alternator, the AC compressor, and the water pump. So to explain that a little bit further, the engine basically uses it's own power to run all the pulleys together starting at the crankshaft pulley or the drive pulley. Now this particular pulley can actually be reduced in size to use less power which can eventually use less power on the engine and free up around 10 to 15 horsepower. So right here I wanna mention that freeing up 10 to 15 horsepower does not mean that you're gonna gain 10 to 15 horsepower from adding underdrive pulleys. What that basically means is now instead of using that extra power on the factory pulleys, you have underdrive pulleys in their place and that power can be redirected to other performance mods, such as the bolt-ons like a cold air intake, intake manifold, cylinder heads, cam, exhaust, things of that nature. Now you have the ability to add 10 to 15 horsepower with other mods such as those.Now another valid question you might be asking is, if you're reducing the size of the crankshaft pulley, wouldn't that mean that you're alternator isn't running at full capacity, which of course affects a lot of different things in the engine and the car alone? Now that's a valid question for sure, but of course when you're reducing the crankshaft pulley size, you're also gonna compensate by adding other pulley sizes as well. The changing in these sizes of the pulleys can actually reduce the amount of stress going on the engine and it'll run absolutely at maximum potential, of course. Now if you're running a smaller pulley for the alternator which we have here with the underdrive pulleys and you're running, like, a massive amplifier in your trunk, you might see a little less power, but of course it's nothing to really ruin any driveability, you just wanna make sure you're checking with your amperage and things of that nature with your alternator as well as your amp.So everything you can expect as far as pulleys are concerned, you can see right here on the table with me today. Everything you see here, you would get a crank pulley, an alternator pulley, and of course a water pump pulley. Now all these come in with SR Performance being one of the most budget-friendly options on the market. Now reducing the parasitic drive train loss is very simple with just shy of a hundred bucks. Now my personal opinion, it's not too bad of a price for this considering you'll be freeing up 10 to 15 horsepower. Now redirecting that power could definitely mean the w

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation

      Features & Specs

      • Free Up Horsepower
      • Complete 3 Piece Kit
      • Durable, Lightweight Aluminum
      • Polished Finish
      • Premium Quality Construction
      • Fits 1986-1993 5.0L V8 Mustangs


      Free Up Horsepower. A set of SR Performance Underdrive Pulleys reduce parasitic drivetrain loss by cutting down the amount of power your accessories take up, these underdrive pulleys will free up 10+ horsepower, without sacrificing cooling and charging functionality of your Pony.

      Premium Quality Construction. CNC-machined from lightweight aircraft grade quality aluminum alloy for strength and durability, these SR Performance pulleys feature a bright polished finish that will give your engine bay an eye-catching high performance appearance.

      Easy Installation. These SR Performance Mustang Underdrive Pulleys installs quickly and easily in under 2 hours with no modifications required.

      Application. This SR Performance 3-Piece Aluminum Underdrive Pulley Kit is designed for use on 1986 to 1993 Ford Mustangs equipped with the iconic push rod 5.0L V8 engine, including the LX 5.0, GT and SVT Cobra models. Reuses stock belt.

      SR Performance



      SR Performance 525568

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) water pump pulley
      • (1) alternator pulley
      • (1) crank pulley
      • (4) bolts


      Customer Reviews (491)

        Questions & Answers

        10 More Questions

        Will It Fit My Mustang

        • Cobra - 93
        • Cobra R - 93
        • GT - 87, 88, 89, 90, 91, 92, 93
        • LX - 87, 88, 89, 90, 91, 92, 93
        • Other - 86

        Fits 5.0L V8's Only

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