Login for Access to Member Pricing

Holley

HOLLEY BBC Accessory Drive Sys. Mid Mount - Black

MPN: 20-242bk Catalog #: 001509261 Category: Pulley Kits Check Vehicle Fitment

Product Details

Pulley Kit - 6-Rib Serpentine - Aluminum - Black Anodized - Big Block Chevy - Kit

Mid-Mount Complete Accessory Drive System; Black; Cast Aluminum; 1.4 in. Inlet Size; Incl. Water Pump/Alternator/Power Steering Pump/Billet Alternator; For Chevy Big Block;

Holley's Mid-Mount accessory drives are now available for your big block Chevrolet engines! The revolutionary system does what no other accessory bracket system has done €¦ GETS RID OF THE BRACKETS! The Mid-Mount complete accessory system has all accessories pulled in tighter than other accessory drives. At the heart of the system is a bracketless design (Patent Pending), where the accessories bolt directly to the water pump for a clean, integrated form. The design offers superb engine visibility to show off your horsepower, not your accessories. The Holley designed alternator is just as innovative. This premium alternator utilizes 6-phase technology as found on the C7 Corvette. The water pump also shares its design efficiencies with that of the C7 Corvette. The compact and reliable SD7 A/C compressor and Type II P/S pump with baffled reservoir are also integrated. The water pump design incorporates optional side or top heater ports. The top thermostat bypass and heater ports are recessed into the manifold. So if you don't need them, you don't see them! When we say complete, we mean complete. The Mid-mount system comes with everything you need. All accessories are included; the water pump, A/C compressor, Alternator, and P/S pump with reservoir. All pulleys and the belt are supplied. Even A/C line adapter, heater hose adapters, power steering to -6 AN hardline, and the alternator plug/harness are included. Easy assembly was a priority during the entire development of this accessory solution. Color graphical instructions walk you through every step of the ultra-easy installation.

DETAILS:

Part Number 20-242BK SPECS:

Holley's Mid-Mount accessory drives are now available for your big block Chevrolet engines! The revolutionary system does what no other accessory bracket system has done… GETS RID OF THE BRACKETS! The Mid-Mount complete accessory system has all accessories pulled in tighter than other accessory drives. At the heart of the system is a bracketless design (Patent Pending), where the accessories bolt directly to the water pump for a clean, integrated form. The design offers superb engine visibility to show off your horsepower, not your accessories. The Holley designed alternator is just as innovative. This premium alternator utilizes 6-phase technology as found on the C7 Corvette. The water pump also shares its design efficiencies with that of the C7 Corvette. The compact and reliable SD7 A/C compressor and Type II P/S pump with baffled reservoir are also integrated. The water pump design incorporates optional side or top heater ports. The top thermostat bypass and heater ports are recessed into the manifold. So if you don't need them, you don't see them! When we say complete, we mean complete. The Mid-mount system comes with everything you need. All accessories are included; the water pump, A/C compressor, Alternator, and P/S pump with reservoir. All pulleys and the belt are supplied. Even A/C line adapter, heater hose adapters, power steering to -6 AN hardline, and the alternator plug/harness are included. Easy assembly was a priority during the entire development of this accessory solution. Color graphical instructions walk you through every step of the ultra-easy installation.

DETAILS:

  • Holley Performance Emission Code 5: This part is legal for sale or use on Emissions Controlled Vehicles; Uncontrolled (Non-Emissions Controlled) Vehicles; and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations
  • Accessory Drive Component Mount Set
  • Mid-Mount Complete Accessory Drive System
  • All Accessories Pulled In Tighter Than Other Accessory Drives
  • Available In Natural And Black Finishes
  • Billet Alternator; Tensioner; And Compressor Pulley Covers
  • Bracketless Accessory Mounting With Ultra-Easy Assembly
  • Compact SD7 A/C Compressor With Line Adapter Included
  • LT1 Style Premium Alternator
  • LT1 Style Water Pump Design
  • O-Ring Seal To Engine
  • OE Pulley Ratios For Optimal Accessory Performance
  • P/S Adapter Hardline To AN -6 Adapter Included
  • Type II Power Steering Pump With Baffled Reservoir
  • COMP-MID-MT ACC DRIVE SYSTEM; BBC-BLACK
  • AccessoryDriveCmpKit

Part Number 20-242BK SPECS:

  • WARNING CA Proposition 65: No

Vehicle Fitment

Universal or product-specific fitment. Please review the product details and contact us if you need help confirming fitment before ordering.

Engine Compatibility

GM - BBCMatched variant: BBC

Big Block Chevy; 396/427/454/572

Fitment note: Engine compatibility is provided as a guide. Please verify all fitment details before ordering.

Product Specs

Brand
Holley
Part Number
20-242bk
Catalog Number
001509261
Product Line
Pulley Kits
Category
Engines & Parts
Type
Pulley Kits
UPC / Barcode
090127072813
Length
24.50 in
Width
18.50 in
Height
17.00 in
Weight
60.21 lb
Freight / LTL
175.00
Ship Alone
Yes
Air Restricted
No
Hazmat
No
Chemical
No
Non-Returnable
No
Case Quantity
1
Kit
No

Shipping & Availability

Current status 9 Available - Ready to ship
Estimated timing Usually ships within 24hrs

This item is showing available inventory. Most in-stock performance parts ship quickly, but timing can vary by warehouse, vendor cut-off time, holidays, and carrier pickup.

Inventory shown: 9 available as of 6/3/2026.

Reviews & Questions

Real product feedback when available, plus quick ways to get fitment or product help.

Ask a Question
Need fitment help? Send us your year, make, model, engine, and the part number.
Already bought it? Reviews help other LMPerformance customers choose the right part.
Product question? We can help with specs, shipping, availability, and install details.

Other Popular Pulley Kits

$2,202.95
^