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Michigan Motorsports LS Head Bolt Kit | Fits 1997-2003 LS1 LS6 LQ4 LQ9 LM7 LR4 4.8L 5.3L 5.7L 6.0L | Replaces GM #12498545 | Premium Cylinder Head Bolt Set

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$41.99 cheaper than the new price!!

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Product details

Management number 213968849 Release Date 2026/04/12 List Price $28.00 Model Number 213968849
Category

The Michigan Motorsports LS Head Bolt Kit is a direct replacement for GM part number 12498545 and is designed specifically for 1997–2003 LS engines. Built to meet or exceed OEM specifications, these torque-to-yield bolts provide the clamping force necessary to keep your cylinder heads sealed under stock and performance conditions. Perfect for rebuilds, head gasket replacements, or top-end upgrades, this kit offers complete coverage for LS1, LS6, LQ4, LQ9, LM7, and LR4 platforms. Whether refreshing a high-mileage daily driver or assembling a street/strip build, Michigan Motorsports delivers the OEM-quality hardware you can trust.

  • OEM Replacement for GM 12498545 – Direct-fit head bolt kit for 1997–2003 LS engines, ensuring factory-level reliability and performance.
  • Complete Cylinder Head Bolt Set – Includes all the torque-to-yield bolts required to fasten both cylinder heads, eliminating the need to piece together hardware separately.
  • Built for Stock & Performance Applications – Provides the clamping force necessary to secure cylinder heads under daily driving or high-performance conditions.
  • High-Strength Construction – Manufactured to meet or exceed OEM tensile strength and torque specifications, ensuring consistent performance and long-term durability.
  • Wide LS Engine Compatibility – Fits 4.8L, 5.3L, 5.7L, and 6.0L LS engines including LS1, LS6, LQ4, LQ9, LM7, and LR4, making it versatile for many GM builds.
UPC 810144060934
Brand Michigan Motorsports
Model K6100
Set Name LS Head Bolt Kit
Head Type Hex
Size Name Bolts for 2 Heads
Unit Count 1 Count
Part Number AJ251
Thread Size M15x1.5, M10x1.5, M5x1.5
Thread Type Unc (Unified Coarse)
Finish Types Zinc Plated
Manufacturer Michigan Motorsports
Thread Class 3B
Thread Style Right Hand
Fastener Size 155mm, 100mm, 45mm
Fastener Type Hexagon Bolt
Item Hardness Grade 3
Material Type Alloy Steel
Thread Coverage Fully Threaded
Screw Head Style Hex
Manufacturer Grade Grade 3
Compatible Groove Diameter 0.31 Inches
Global Trade Identification Number 00810144060934

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