Part #: 260 - 4704. If you're aiming for 500 - 675whp, these ARP head studs are perfect for your Subaru WRX and STI. ARP uses high - grade 8740 chrome moly, better than 'aircraft' quality. Each stud is vertically placed in special racks and precisely heat - treated to 270,000 psi. They feature a 12 - point style nut and are OE - 11mm sized, with a 4mm Allen head for threading into the block. ARP studs are made with exacting tolerances, allowing gaskets and cylinder heads to fit smoothly and align perfectly. Thread - rolled after heat - treat, they have ten times better fatigue strength than pre - heat - treat threaded studs. Each kit includes premium parallel ground washers. A must for performance engines with increased boost, they're the best on the market for your WRX or STI.
Using these ARP head studs is easy. First, make sure your engine is clean and ready for installation. Use the 4mm Allen tool to thread the studs into the block. Then, attach the 12 - point style nuts. The OE - 11mm size ensures a proper fit. When installing, ensure that gaskets and cylinder heads are properly aligned as the studs help them glide into position. For maintenance, check the studs regularly for any signs of wear or damage, especially if your engine runs at high boost levels. Keep them clean to prevent corrosion. If you notice any issues, it's best to replace the studs promptly to maintain engine performance.
