Reinforced ARP main studs for VAG 2.0 TFSI EA113 EA888

The VAG engines concerned

This kit covers the 2.0 TFSI and TSI engines of the Volkswagen group: the EA113 family (2004 to 2010) and the EA888 family, from the first generation (2008) to generations 3 and 4 (since 2013). They power the Audi A3, S3, A4, TT and TTS, the Volkswagen Golf GTI and R, the Seat Leon Cupra and the Cupra Leon, among others.

Reinforced ARP studs for main bearings

On a crankshaft, the main caps are what hold the shaft against the loads passed on by the connecting rods. If their clamping force drops, the cap shifts slightly on its parting line at every cycle: the bearing surfaces are marked by brinelling, then the bearing bore goes out of round.

This kit replaces the original main cap bolts with 10 mm ARP2000 studs, with their nuts and washers as the ARP instruction sheet lists them. Each stud is screwed into the block by hand and the caps are fitted over them; threads, nuts and washers receive the ARP assembly lubricant supplied with the kit, then the nuts are torqued in three passes. Preload is higher and more consistent, and the block threads are preserved.

Material: ARP2000, an alloy steel developed by ARP, rated at 220,000 psi tensile strength, with threads rolled after heat treatment. Against classes 10.9 and 12.9 of standard fasteners, between 150,800 and 176,900 psi minimum, it offers 24 to 46% more strength. On this four-cylinder engine, the ARP2000 studs in M10 x 1.5 are rated for 1,100 hp at most (calculated estimate).

Technical specifications

Tightening torque

No torque is applied to the stud as it goes into the block: it is screwed in by hand. For a permanent installation, the instruction sheet leaves the option of a thread locker of the blue Loctite type on the block end, with the nuts fully tightened before it cures, never on the nuts and never mixed with ARP grease.

The nuts are tightened in the sequence the manufacturer specifies for the main caps; the instruction sheet supplied with the kit describes the full procedure.

Stronger fasteners change the clamping force: the size and roundness of the main bearing bores are checked after installation, and the bores are align honed if necessary, using the final fasteners and lubricant.

The torque figures above come from the ARP 204-5408 instruction sheet, revision applicable at publication. The official instruction sheet is authoritative in the event of any difference. Read the ARP 204-5408 instruction sheet

Technical guide

All the torque values on this page assume ARP assembly grease; with engine oil they are no longer correct.

The ARP brand

Coming from the aerospace industry, Gary Holzapfel founded ARP (Automotive Racing Products) in 1968 to put an end to engine failures caused by weak fasteners in motorsport. The company designs and manufactures thousands of part numbers in California, in several material grades depending on the application.

Advantages over the original bolts

Criterion	Original main bolts	ARP studs
Tightening	Bolt turned straight into the block	Nuts tightened in three passes, steady build-up
Block threads	Loaded by the turning bolt at every tightening	Stud screwed in by hand, no torque load
Refitting the caps	Cap held by hand while the bolts go in	Cap guided by the studs

When studs become necessary

• Power increase from a turbo, supercharger or higher boost
• Stroker crankshaft or higher rev limit
• Complete bottom end strip-down
• Bearing bores or block threads already fatigued
• Intensive motorsport use

Vehicle compatibility

Why is it the most cost-effective solution?

On a tuned 2.0 TFSI, with a larger turbo or an aggressive remap, ARP2000 studs clamp the main caps more firmly than the original bolts and limit the risk of bottom-end damage. Their cost stays low next to the cost of rebuilding a crankshaft and a block.