Motorsports LS Head Bolt Kit for LS1, LS6, LQ4, LQ9, LM7 4.8L, 5.3L, 5.7L, 6.0L (Bolts for 2 Heads)

The stock-replacement cylinder head bolts that are torque-to-yield and are built to the same specs as GM # 12498545 are presented here. These bolts are of the Gen-3 design, utilizing three different bolt lengths, and were used by GM from 1997 through mid-year 2004.

It is important to note the specific head bolts required, as GM used two different styles of LS head bolts during this period. From 1997 to 2003, the heads used 8 bolts that were 155mm in length, 2 bolts that were 100mm in length, and 5 bolts that were 45mm in length. In contrast, the heads used from 2004 to 2014 utilized 10 bolts that were 100mm in length and 5 bolts that were 45mm in length.

These cylinder head bolts are torque-to-yield, meaning they cannot be reused after being torqued down, as they will stretch when subjected to the required torque. Therefore, two sets of these bolts are needed per engine to ensure proper installation and operation.

When ordering, customers should select the appropriate option to acquire the necessary fasteners for one or both cylinder heads, depending on the specific requirements of their engine. By carefully choosing the correct head bolts, users can ensure a proper and secure installation, maintaining the integrity and performance of their GM engines.

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