SpeedFactory Titanium Manifold Stud M8x1.25x45mm (Single)

Snapped an exhaust manifold stud on your B18 pulling the header off, or stripped one swapping intake manifolds on a D16? You don't need to buy a whole kit to fix one bad fastener. This is a single SpeedFactory titanium manifold stud in M8x1.25x45mm, complete with a titanium 12-point nut and washer, sold one at a time so you can replace exactly what broke.

What It Is and Why It Works

SpeedFactory machines these studs from Ti 6Al-4V, the same Grade 5 titanium used in aerospace fasteners. It's stronger than the factory steel hardware and it will not rust, which matters because rust is exactly why factory Honda exhaust studs snap when you try to remove them after 25 years of heat cycles. Each stud has a 3mm hex key tip machined into the end, so it threads into the head with an Allen key instead of the double-nut trick. The complete stud, nut, and washer assembly weighs about 12 g, per manufacturer.

The M8x1.25 thread pitch covers the intake and exhaust manifold studs on Honda and Acura B series (B16, B18, B20), D15 and D16, F20B, the S2000's F20C and F22C, and the Prelude's H22 and H23. It also matches the intake manifold side of a K series head. It does not fit the K series exhaust side, which uses M10x1.25, so K swap guys chasing header hardware need the M10 version instead.

The 45mm length is the right call for exhaust manifolds, headers, and stock intake manifolds. If you're running an aftermarket intake manifold or a thermal gasket stack, the extra flange thickness usually calls for the 55mm or 65mm version, which SpeedFactory also offers as singles. Measure your stack before ordering and you won't be doing this job twice.

Specs

Available Options

Fitment

Thread pitch is what decides fitment here, not the chassis. Any Honda or Acura manifold location using an M8x1.25 stud takes this part, including B16 Civics, B18A and B18B Integras, and swapped EG, EK, and DC2 builds running B, D, F, or H series power. Confirm your original hardware is M8x1.25 before ordering.

What to Know Before You Buy

Thread the stud in by hand first to make sure the bore is clean, then snug it with the 3mm Allen key. Don't crank on the hex tip, it's an install feature, not a torque point. The clamping force comes from torquing the nut to your factory manifold spec, same number you'd use with steel hardware. Titanium in an aluminum head can gall, so run a nickel-based anti-seize on the threads, especially on exhaust and turbo manifold duty, and plan to retorque after a few heat cycles.

If you're replacing one broken stud on an otherwise tired manifold, take a hard look at the rest of them while you're in there. Studs that survived the same 25 years of heat cycles are usually next in line, and doing the full set once beats chasing exhaust leaks one stud at a time. For that job, grab the SpeedFactory 10-piece titanium manifold stud kit we carry instead, it covers a full B, D, F, or H series manifold with spares left over.