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Holley 20-135 Drivers Side P/S & Alternator LS Acc Drive Bracket Kit
Holley 20-135 Drivers Side P/S & Alternator LS Acc Drive Bracket Kit

Holley 20-135 Drivers Side P/S & Alternator LS Acc Drive Bracket Kit

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Holley 20-135 Drivers Side P/S & Alternator LS Acc Drive Bracket Kit
Holley 20-135 Drivers Side P/S & Alternator LS Acc Drive Bracket Kit
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Part # 42520135
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  • Get FREE shipping when your order includes this item and exceeds $99! Ground shipping only in the contiguous US.


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These accessory drive brackets from Holley are great when swapping a GM LS engine into a muscle car, truck, hot rod or other vehicle. These brackets were designed to deliver a factory style appearance, correct belt alignment, and factory stability. Holleys kits supply the required brackets and hardware needed for installation.

To determine correct application, these three easy steps will help get you going:

  • Step one is to determine your belt alignment based on your crank Pulley position on the engine you have.
  • Step two is to choose the Holley accessory drive brackets that you need (A/C, Alt & P/S or both).
  • Step three is to see which Holley installation kit your set–up requires to line up your accessories with your crank Pulley position. An application specific installation kit (part # 425-211, 425-212, or 425-213) is REQUIRED for most applications.

Note: When referring to guide links below, keep in mind that part numbers shown are MFG numbers without "425" prefix.

Fitment and Required Components Guide for 20-135 Bracket Kit (PDF)

Assembly Instructions for Holley 20-135 Accessory Drive Kit (PDF)


Item Details

NOTE: This bracket MAY REQUIRE an installation kit for assembly
(Part 425-212 OR 425-213, see Fitment Guide for details).


Holley's kits supply the required brackets and hardware needed for installation, but allow you to choose the source for supplemental accessories and components that are often already on the donor engine or host vehicle. Whether sourcing from the salvage yard, the local auto parts store, your GM parts dealer, or Holley, you pick the accessories that match your needs and budget!

Key Features:

  • The most cost effective LS bracket solution on the market!
  • Universal brackets fit virtually all common LS engines regardless of water pump and harmonic balancer offsets reducing cost and complexity compared to competitive products
  • Simple, dedicated installation kits allow easy fitment to Corvette, F–Body or Truck drive offsets
  • Utilizes commonly available and affordable GM alternators and power steering pumps
  • OEM quality natural finish die castings for clean looks and durability. Can be polished, coated, painted or plated.
  • OEM spec flanged head hardware included to match your factory LS engine hardware
  • Complete accessory drive kits include all components and accessories
  • Ideal for crate engines, take out motors and engine builders!
Some parts are not legal for use in California or other states with similar laws/regulations

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