{"product_id":"speedfactory-extreme-pro-duty-ca625-head-stud-kit-b-k-series","title":"SpeedFactory Extreme Pro Duty CA625+ Head Stud Kit for B\/K Series","description":"\u003cul\u003e\n\u003cli\u003eFits B and K Series Engines \u003c\/li\u003e\n\u003cli\u003e37-40% Stronger Than Other Head Stud Kits \u003c\/li\u003e\n\u003cli\u003e9\/16\" 12 Point Nuts for Superior Clamping \u003c\/li\u003e\n\u003cli\u003eNot Suitable for Complete B20 or B18A\/B or K24Z Engines \u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c!-- split --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli\u003e\u003ca class=\"active\" href=\"#Description\"\u003eDescription\u003c\/a\u003e\u003c\/li\u003e\n \u003cli\u003e\u003ca href=\"#VehicleFitment\"\u003eVehicle Fitment\u003c\/a\u003e\u003c\/li\u003e \u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\n\n\u003cli class=\"active\" id=\"Description\"\u003e\n\u003ch3\u003eSpeedFactory Extreme Pro Duty CA625+ Head Stud Kit - B \u0026amp; K Series VTEC\u003c\/h3\u003e\n\n\u003cp\u003eWhen you're boosting a B or K series past 30 psi, the head studs are what stand between combustion pressure and a lifted head. This is the strongest kit SpeedFactory offers, built from ARP's Custom Age 625+ material, 37 to 40% stronger than standard off-the-shelf studs. It's for hardcore drag builds where clamping force matters more than cost.\u003c\/p\u003e\n\n\u003ch4\u003eIt Needs A VTEC Head, Not A VTEC Engine\u003c\/h4\u003e\n\n\u003cp\u003eRead this carefully, because it's the fitment gate and it catches people out on hybrid builds.\u003c\/p\u003e\n\n\u003cp\u003eThis kit fits \u003cstrong\u003eVTEC heads\u003c\/strong\u003e. What matters is the head, not the block, and that distinction is everything on a swapped or hybrid engine.\u003c\/p\u003e\n\n\u003cp\u003eSo it fits a genuine VTEC engine like a B16A, B18C, K20, or K24. It also fits an \u003cstrong\u003eLS-VTEC or B20-VTEC build\u003c\/strong\u003e, where a VTEC head sits on a B18A, B18B, B20B, or B20Z block, because the head is the VTEC part.\u003c\/p\u003e\n\n\u003cp\u003eWhat it does \u003cstrong\u003enot\u003c\/strong\u003e fit is a complete non-VTEC B-series, meaning a B18A or B18B with its original non-VTEC head. No VTEC head, no fit.\u003c\/p\u003e\n\n\u003cp\u003eIf you're running a hybrid, go by your head. If you've put a VTEC head on a non-VTEC block, this is your kit. If your engine is non-VTEC top to bottom, it isn't.\u003c\/p\u003e\n\n\u003ch4\u003eWhy CA625+ Over Standard Studs\u003c\/h4\u003e\n\n\u003cp\u003eThe material is the entire product, so it's worth understanding what you're paying for.\u003c\/p\u003e\n\n\u003cp\u003eMost head studs, including ARP's own standard kits, use 8740 chromoly. That's good material and it's fine for most builds. CA625+ is a different tier entirely.\u003c\/p\u003e\n\n\u003cp\u003eIt's \u003cstrong\u003e37 to 40% stronger\u003c\/strong\u003e than standard studs, with 260,000 to 280,000 psi tensile strength. That translates directly into more clamping force, which is what keeps the head sealed against the block when cylinder pressure is trying to lift it.\u003c\/p\u003e\n\n\u003cp\u003eIt also has roughly \u003cstrong\u003e17% higher yield strength than ARP L19\u003c\/strong\u003e, which means it takes a higher initial torque and higher cyclical loading before it starts to stretch. On a drag engine seeing repeated extreme boost, that fatigue resistance is what keeps the clamp load consistent over time.\u003c\/p\u003e\n\n\u003ch4\u003eNo Special Handling\u003c\/h4\u003e\n\n\u003cp\u003eThis is a practical advantage over the other high-strength option.\u003c\/p\u003e\n\n\u003cp\u003eL19 is strong but fussy. It's susceptible to stress corrosion and hydrogen embrittlement, which means it needs careful handling, oiling, and storage or it can fail from corrosion rather than load.\u003c\/p\u003e\n\n\u003cp\u003eCA625+ is immune to both. It needs no special handling, doesn't require you to keep it oiled on the shelf, and won't quietly degrade from corrosion. You get L19-and-beyond strength without the babysitting.\u003c\/p\u003e\n\n\u003ch4\u003eBuilt For Easier Installation\u003c\/h4\u003e\n\n\u003cp\u003eTwo details that make the job less painful.\u003c\/p\u003e\n\n\u003cp\u003eThe studs have a \u003cstrong\u003e3\/16\" hex broach on top\u003c\/strong\u003e, which lets you thread them in with an Allen key and, importantly, install them with the cylinder head on the car if you need to. That's a real convenience on an engine that's already in the bay.\u003c\/p\u003e\n\n\u003cp\u003eThe kit uses \u003cstrong\u003eoversized forged 9\/16\" 12-point nuts and hardened parallel-ground washers\u003c\/strong\u003e rather than the smaller 1\/2\" hardware most kits ship. The larger contact area distributes clamp load better across the head, which is part of getting even sealing at high pressure.\u003c\/p\u003e\n\n\u003ch4\u003eDirect Replacement, No Machining\u003c\/h4\u003e\n\n\u003cp\u003eThese drop in where the factory head bolts came out. No modification to the head or block, no machining, nothing to adapt.\u003c\/p\u003e\n\n\u003cp\u003eEach kit includes 10 CA625+ studs, the nuts and washers, ARP Ultra-Torque assembly lubricant, and instructions. Use the supplied lubricant, since torque specs are calculated around it and substituting something else changes the clamp load you actually get.\u003c\/p\u003e\n\n\u003ch4\u003eFitment\u003c\/h4\u003e\n\n\u003cp\u003e1994-2001 Acura Integra GS, LS, RS, and GS-R\u003cbr\u003e1997-2001 Acura Integra Type R\u003cbr\u003e2002-2006 Acura RSX\u003cbr\u003e2004-2008 Acura TSX\u003cbr\u003e1999-2000 Honda Civic Si\u003cbr\u003e2002-2005 Honda Civic Si\u003cbr\u003e2006-2011 Honda Civic Si\u003cbr\u003e2002-2006 Honda CR-V\u003cbr\u003e1994-2001 Honda Del Sol VTEC\u003cbr\u003e2003-2011 Honda Element\u003c\/p\u003e\n\n\u003cp\u003eCovers B16A, B18C1, B18C5, B20-VTEC, LS-VTEC, K20A, K20Z, and K24A. \u003cstrong\u003eRequires a VTEC head.\u003c\/strong\u003e Does not fit complete non-VTEC B18A\/B18B engines or the K24Z7.\u003c\/p\u003e\n\n\u003ch4\u003eWho Should Run These\u003c\/h4\u003e\n\n\u003cp\u003eThis is for the drag or high-boost builder who's decided the head studs aren't the place to compromise. Past 30 psi, the strongest material available, no special handling, and clamping force that holds the head down when everything else is trying to lift it. Confirm you're running a VTEC head, use the supplied lubricant, and torque them properly.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eFits:\u003c\/strong\u003e Honda and Acura B and K series with a VTEC head, see the application list above. \u003cstrong\u003eMaterial:\u003c\/strong\u003e ARP Custom Age 625+, 260,000-280,000 psi tensile. \u003cstrong\u003eStrength:\u003c\/strong\u003e 37-40% over standard studs, ~17% higher yield than L19. \u003cstrong\u003eHardware:\u003c\/strong\u003e oversized 9\/16\" 12-point nuts and parallel-ground washers, 3\/16\" hex broach. \u003cstrong\u003eIncludes:\u003c\/strong\u003e 10 studs, nuts, washers, ARP Ultra-Torque lubricant, instructions. \u003cstrong\u003eRecommended for:\u003c\/strong\u003e boost above 30 psi. \u003cstrong\u003eRequires:\u003c\/strong\u003e VTEC head. \u003cstrong\u003eDoes not fit:\u003c\/strong\u003e complete non-VTEC B18A\/B18B, or K24Z7.\u003c\/p\u003e\n\u003c\/li\u003e\n\n \n\u003cli id=\"VehicleFitment\"\u003e\n \u003cp\u003e1994-2001 Acura Integra GS\/LS\/RS\u003cbr\u003e1994-2001 Acura Integra GS-R\u003cbr\u003e1997-2001 Acura Integra Type R\u003cbr\u003e2002-2006 Acura RSX\u003cbr\u003e2004-2008 Acura TSX\u003cbr\u003e1999-2000 Honda Civic Si\u003cbr\u003e2002-2005 Honda Civic Si\u003cbr\u003e2006-2011 Honda Civic Si\u003cbr\u003e2002-2006 Honda CR-V\u003cbr\u003e1994-2001 Honda Del Sol VTEC\u003cbr\u003e2003-2011 Honda Element\u003c\/p\u003e \n\u003c\/li\u003e\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\u003c\/ul\u003e\n","brand":"SpeedFactory","offers":[{"title":"Default Title","offer_id":47653962055714,"sku":"SFR-02-005","price":649.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/2218\/5701\/files\/SFR-02-005_jyga.jpg?v=1789744747","url":"https:\/\/www.hybrid-racing.com\/products\/speedfactory-extreme-pro-duty-ca625-head-stud-kit-b-k-series","provider":"Hybrid Racing","version":"1.0","type":"link"}