{"product_id":"arp-pro-series-main-bolt-kit-hex-for-02-14-subaru-wrx-04-20-sti-ej205-ej257","title":"ARP Pro Series Main Bolt Kit Hex For 02-14 Subaru WRX\/ 04-20 STi EJ205\/EJ257","description":"\u003cp\u003eTake your Subaru EJ-series engine build to the next level with ARP Pro Series Main\/Case Bolts. Engineered from premium 8740 chromoly steel and heat-treated for ultimate strength, these bolts are built to withstand the extreme forces of high-performance and forced induction setups. Featuring rolled threads after heat-treatment and generous under-head radii, ARP bolts deliver superior clamping force, fatigue resistance, and long-term reliability over stock hardware. Whether you're rebuilding a street motor or prepping for track duty, these main bolts offer peace of mind where it matters most.\u003c\/p\u003e\n\u003cp\u003eDesigned for Subaru Impreza WRX (2002–2014) and STi (2004–2020) models, these ARP Case Bolts are a direct upgrade for EJ20, EJ22, EJ25, and EJ257 engines. They're far more durable than OEM bolts that stretch over time, helping to prevent spun bearings and engine failure. Each kit includes parallel-ground hardened washers and hex head fasteners for precision and even torque distribution. For optimal results, professional engine builders recommend line honing the block when using ARP bolts to ensure perfect alignment and eliminate case distortion.\u003c\/p\u003e\n\u003cdiv id=\"gmail-description\"\u003e\n\u003cdiv id=\"gmail-descriptioncontent\"\u003e\n\u003cdiv\u003e\u003cstrong\u003eFeatures:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cul\u003e\n\u003cli\u003eRated at 200,000 psi tensile strength for reliability\u003c\/li\u003e\n\u003cli\u003e8740 chromoly steel construction resists stretching\u003c\/li\u003e\n\u003cli\u003eRolled threads after heat-treating increase fatigue life\u003c\/li\u003e\n\u003cli\u003eIdeal for Subaru EJ20, EJ25, and EJ257 engines\u003c\/li\u003e\n\u003cli\u003eIncludes hardened parallel-ground washers in kit\u003c\/li\u003e\n\u003cli\u003ePrevents main bearing shift and block distortion\u003c\/li\u003e\n\u003cli\u003eDesigned for high-performance and boosted setups\u003c\/li\u003e\n\u003cli\u003eDirect OEM replacement for WRX\/STi main bolts\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eSpecifications:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eMain Bolt Style: 2-bolt\u003c\/li\u003e\n\u003cli\u003eFastener Style: Bolt\u003c\/li\u003e\n\u003cli\u003eHead Style: Hex\u003c\/li\u003e\n\u003cli\u003eWorks with Windage Tray: No\u003c\/li\u003e\n\u003cli\u003eFastener Tensile Strength (psi): 200,000 psi\u003c\/li\u003e\n\u003cli\u003eNuts Included: No\u003c\/li\u003e\n\u003cli\u003eWashers Included: Yes\u003c\/li\u003e\n\u003cli\u003eQuantity: Sold as a kit\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eIncluded:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e(1) Head Stud Kit\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003cstrong\u003eFitment:\u003c\/strong\u003e\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e2002–2014 Subaru WRX 2.0L EJ205\u003c\/li\u003e\n\u003cli\u003e2004–2020 Subaru WRX STi 2.5L EJ257\u003c\/li\u003e\n\u003cli\u003e2006–2014 Subaru WRX 2.5L EJ255\u003c\/li\u003e\n\u003cli\u003e2005–2009 Subaru Legacy GT 2.5L EJ255\u003c\/li\u003e\n\u003cli\u003e2005–2009 Subaru Outback XT 2.5L EJ255\u003c\/li\u003e\n\u003cli\u003e2004–2006 Subaru Baja Turbo 2.5L EJ255\u003c\/li\u003e\n\u003cli\u003e2004–2013 Subaru Forester XT 2.5L EJ255\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv\u003e\n\u003cul\u003e\n\u003cli\u003eLifetime Warranty  \u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"ARP","offers":[{"title":"Default Title","offer_id":46682703954077,"sku":"260-5401","price":507.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0645\/2504\/1821\/files\/Screenshot2025-04-17093949.png?v=1744898385","url":"https:\/\/rudysdiesel.com\/products\/arp-pro-series-main-bolt-kit-hex-for-02-14-subaru-wrx-04-20-sti-ej205-ej257","provider":"Rudy's Performance Parts","version":"1.0","type":"link"}