What to know:
The ARP RB26 Head Studs come as a complete kit to upgrade the hardware on your engine.
This is one of the most common upgrades found on any upgraded RB26 build. They can be found used on builds running stock pistons and stock head gasket all the way to forged internals and metal gaskets. ARP is known for its quality and is superior to those lesser grade studs out there. These studs are also easy to handle as there is no immediate shelf life or special handling procedure from common contamination (ie: the L19 handling procedures).
Factory head studs (commonly very aged when found in an used engine) can allow for the cylinder head to lift under higher boost and pressure conditions. Ultimately, causing for a blown head gasket and/or other damage to the engine. The additional clamping load this ARP head stud kit achieve allow for higher boost and combustion chamber pressure to be ran on your RB26.
The technical info:
The ARP2000 material used on these studs is a heavily alloyed martensitic quench and temper steel, initially developed for use in steam power plants. As such it has excellent stability at high temperatures. But most important, ARP research discovered that in addition to temperature stability it has excellent notch toughness in the higher strength ranges and is alloyed to be tempered to Rc44/47. Premium grade 8740 alloy and 4340 can be tempered to the same hardness. But, the tempering temperature would yield material in the “temper brittle zone” (between 500° and 700°F), producing significant notch sensitivity. ARP2000 is an alloy steel that can be safely heat treated to a higher level, producing a greater strength material than 8740. While 8740 and ARP2000 share similar characteristics – ARP2000 is capable of achieving a clamp load at 220,000 psi (where others alloys are treated to 200,000 psi). ARP2000 is used widely in short track and drag racing as an upgrade from 8740 chrome moly in both steel and aluminum rods. Stress corrosion and hydrogen embrittlement are typically not a problem, providing care is taken during installation.
What is included:
- 14x Studs
- 14x Washers
- 14x Nuts
Socket Size Reference:
ARP provides the following instructions for proper installation of these studs for this kit:
- Always verify the part number for your application with the part number on the side of box and the part number on the instruction sheet. This will help ensure you have the correct installation procedure for your specific application before installing any components.
- Clean and inspect all hardware prior to installation. Look for obvious defects or shipping damages, plus proper fit, length and dimension.
- To ensure proper thread engagement and accurate torque readings, clean ALL threads in the block. Chase if necessary with ARP Thread Chaser, part number 912-0007 (M12 X 1.5).
- If the cylinder head studs protrude into a water jacket, lubricate the block threads of the studs with ARP THREAD SEALER.
- Screw studs into the block “HAND TIGHT ONLY”.
- NOTE: LOCTITE MAY BE USED IF A PERMANENT MOUNTING OF THE STUDS IS PREFERRED. THE
- FASTENERS, HOWEVER, MUST BE TORQUED PRIOR TO THE LOCTITE SETTING UP.
- Install the cylinder head(s) and check for binding or misalignment.
- Lubricate the stud threads, nuts and washers with ARP ULTRA-TORQUE FASTENER ASSEMBLY LUBRICANT.
- Then install the washers and the nuts onto the studs and tighten them hand tight. ARP recommends using the ARP ULTRA-TORQUE FASTENER ASSEMBLY LUBRICANT that is provided with each kit as opposed to motor oil. This is due to higher friction on the studs as well as inconsistencies in the clamping force of the fasteners when motor oil or other low quality lubricants are used.
- PRELOAD (TORQUE) RECOMMENDATIONS
- Following the manufacturers recommended torque sequence tighten the nuts in three equal steps to 105 ft lbs with ARP ULTRA-TORQUE FASTENER ASSEMBLY LUBRICANT.
Note: ARP Ultra-Torque Fastener Assembly Lubricant has been specifically designed to reduce tension preload scatter and eliminate the need to cycle high performance engine fasteners before final installation. ARP Ultra-Torque far surpasses all requirements offered by previous ARP lubricants in terms of fastener preload repeatability and performance lubricating properties.