Speed 21 V-SPEC M3x16 Flange Hex Socket Head Screws Pack of 10 - OS79871162 O.S. Engine  [OS79871162]

Engine head flange socket screws, M3x16 size

This kit supplies ten M3x16 flange hexagon socket head screws intended for cylinder head retention on engines referenced as Speed 21 V-SPEC in the item title. The set is aimed at replacing or servicing the fasteners used on matching cylinder heads and is described specifically for RC engine assembly and head servicing rather than broader hardware uses.

Fitting guidance: confirm that the cylinder head tapped holes match M3 threads and ensure mating surfaces are free of debris. Hand-thread each screw initially to avoid cross-threading and tighten in stages so the flange seats evenly across the head face. Keep spare screws available when performing head removal, shim checks, or gasket replacement to avoid delays.

Why it matters for tuning: these screws do not modify engine performance, but maintaining correct torque and even clamp force helps keep the head sealed, preventing leaks that can upset tuning and on-track consistency.