Upgrade the bottom end of your Gen 3 HEMI with the ARP 244-5400 Main Stud Kit, designed for OE Mopar iron HEMI blocks with cross-bolted main caps. Whether you're assembling a naturally aspirated performance engine, boosted street build, or dedicated race combination, maintaining consistent main-cap clamping is critical as cylinder pressure and engine output increase.
Compared with factory main bolts, ARP main studs provide more consistent and repeatable clamping force while helping reduce main cap movement and fretting. Because the stud remains stationary in the block while the nut is tightened, the fastener is not being twisted into the block at the same time clamping load is applied. This also reduces stress on the block threads and helps maintain accurate main-cap alignment during engine assembly.
ARP manufactures these studs from heat-treated 8740 chromoly steel with threads rolled after heat treatment for increased strength and fatigue resistance. The kit includes the necessary high-strength nuts and hardened, parallel-ground washers.
Features
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ARP Part Number: 244-5400
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Designed for cross-bolted Gen 3 HEMI blocks
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Heat-treated 8740 chromoly steel construction
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Threads rolled after heat treatment for increased fatigue strength
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Provides more consistent main-cap clamping than factory bolts
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Helps reduce main cap walk and fretting
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Reduces stress on the engine block's threaded holes
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Includes high-strength nuts
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Includes hardened parallel-ground washers
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Compatible with factory main caps
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Compatible with HHP Racing Billet Main Caps
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Sold as a complete kit
Engine Applications
Designed for OE Mopar iron Gen 3 HEMI engine blocks, including:
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5.7L HEMI
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6.1L HEMI
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6.2L Supercharged HEMI
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6.4L / 392 HEMI
IMPORTANT: LINE HONE REQUIRED
Installation of aftermarket main studs changes the clamping load applied to the main bearing caps. The engine block must be line honed with the ARP main studs installed and torqued to specification before final engine assembly.
Do not simply replace the factory main bolts with studs in an assembled or previously machined block without checking and correcting the main bearing housing alignment.
IMPORTANT: OIL PAN & WINDAGE TRAY CLEARANCE
The ARP main stud and nut assembly extends farther below the main caps than the factory main bolts. Because of this additional height, clearance must be checked between the main studs, factory windage tray, and OEM oil pan during engine assembly.
When using the factory windage tray and oil pan, clearancing or notching may be required around the main stud locations so the oil pan can sit completely flat against the engine block and rear main seal surface.
Before installing the oil pan gasket or applying sealant, test-fit the oil pan and verify that it rests flat on the block without contacting any of the ARP studs or nuts. The rear of the oil pan should sit flush with the rear main seal housing.
Do not use the oil pan bolts to pull an oil pan into position if interference is present.
Failure to provide adequate clearance can prevent the oil pan from seating correctly and may result in:
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Engine oil leaks
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Improper oil pan alignment
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Difficulty aligning the lower transmission mounting bolts
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Damaged or cross-threaded transmission fasteners
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Transmission-to-engine alignment issues
Any required clearance should be completed during engine assembly, followed by another test fit of the oil pan before the gasket and final sealant are installed.
HHP Installation Recommendation
For performance Gen 3 HEMI engine builds, HHP recommends performing all main-cap machining with the exact fasteners and main caps that will be used during final assembly. If upgrading to ARP main studs or HHP Racing Billet Main Caps, have the block professionally measured and line honed as required before final assembly.
