During the formative years of the high performance industry, the "trick of the week" seemed to come and go on a regular basis. Lots of those tricks revolved around header bolts, and attempting to keep them tight under heat, vibration, and constant pedal mashing bursts of speed. Enter the SplitLock, which gives a whole new twist to the theory of mechanically locking fasteners.
Designed and manufactured by Breslin Performance Products, these innovative bolts (available in 8740 chrome-moly steel or black oxide finish) are comprised of a 3/8, 12-point head, combined with a 9/16 head flange, for additional clearance around your primary tubes. What makes this even more interesting, the center of the bolt is "rifle drilled," or precision machined and threaded, and the lower portion of the threads feature cross cuts. Then, there's a set pin (made of 18-8 stainless steel) that threads into the center of the bolt, which, when locked in position, forces those cross cuts to expand the shank within the bolt hole, ultimately locking the fastener in place.
Gone are the days when header bolts would loosen and immediately cause the gasket to blow out. Now you can put a positive lock on your header bolts. SplitLock fasteners are available for all popular applications.