Acura Integra Head Stud Installation Guide (CP129)
CP129 · B18C1 / B18C5 / LS-VTEC / B20-VTEC
This guide walks through installation of the XOTIC PERFORMANCE CP129 head stud kit, from cleaning the block threads to the final tightening pass. Use it with the CP129 installation manual and the engine service information for your application.
Final torque: 80 ft-lb
Tighten the nuts in three passes: 30 → 50 → 80 ft-lb. Use the supplied fastener assembly lubricant as described below. Install the studs into the block by hand only.
Before you begin
Confirm that CP129 is the correct kit for your engine configuration. The manual identifies B18C1, B18C5, LS-VTEC and B20-VTEC applications. The steps below cover stud installation and tightening; use the engine service information for cylinder-head removal and reassembly.
Have the supplied socket, Allen wrench and assembly lubricant ready, along with a torque wrench, a straightedge and ruler, clean dry cloths, and a fast-evaporating solvent such as non-chlorinated brake cleaner. For cleaning the block threads, the matching tool is the CS320 M11 × 1.50 thread chaser, sold separately.
Installation: steps 1–8
Clean the block threads. Clean the threaded holes before fitting the head studs to support proper thread engagement and accurate torque readings. Use the CS320 thread chaser if needed, and remove the loosened debris before installing the studs.
Install the studs by hand. Thread each stud into the block until snug. Do not apply torque to the studs. The hex broach is for assisting with installation and removal; never use it to torque the stud into the block.
Check stud protrusion. Measure from the block deck to the top of each installed stud using a straightedge and ruler. Studs in the same length group should sit level with each other, within 1 mm / 0.040 in. If a stud sits higher or lower, remove it, re-clean the hole and reinstall it by hand. Do not force a stud deeper with tools.
Install the head gasket and cylinder head. Position both correctly and check alignment as the head is lowered over the studs.
Clean the washer seating areas. Remove oil, grease and contaminants from the washer seating areas on the cylinder head with a fast-evaporating solvent, such as non-chlorinated brake cleaner.
Fit clean, dry washers. Wipe oil from both sides of every washer with a clean, dry cloth, then place the washers over the studs. Keep the washer-to-cylinder-head mating surfaces free of oil and grease.
Lubricate the threads and nuts. Apply a thin coat of the supplied assembly lubricant to the stud threads and the underside of each nut. Thread the nuts onto the studs by hand until they contact the washers.
Tighten in the numbered sequence. Follow the diagram below and complete the full 1–10 sequence at each torque stage before starting the next pass.
Torque settings and tightening sequence
| Pass | Torque |
|---|---|
| Step 1 | 30 ft-lb |
| Step 2 | 50 ft-lb |
| Step 3 — final | 80 ft-lb |
Use the same numbered order for all three passes. Do not exceed the final torque value.
Installation tools and related parts
CS320 — M11 × 1.50 thread chaser: the matching size and pitch for cleaning CP129's block-side threads. The chaser is sold separately; the socket, Allen wrench and assembly lubricant are included with the CP129 kit.
Keep the manual with your build
Download the CP129 installation manual for the printable instructions and tightening diagram.
For help with kit identification or installation planning, contact support@xotic-performance.com. Include your kit number and engine configuration.
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