An external oil feed line is used to supply additional oil to the rocker assembly when the internal channel does not supply sufficient oil. An external feed line may or may not be needed on your engine. Evaluate your oil flow to determine if it is needed. Oil should be flowing out of each rocker, even at idle. Pay special attention to the front rockers as they are the last to receive oil. An unrestricted external feed line may supply too much oil, dropping overall oil pressure. This kit includes a restrictor pin to limit oil flow through the feed line if necessary.
This feed line connects to the main oil gallery at one of the plugs that is pointed down at an angle. Your choice of the one in front of or behind the distributor. The fitting that threads into the block is the correct 1/8″ BSPT which is 28 threads per inch rather than 1/8″ NPT which is 27 threads per inch. Triumph blocks are threaded 1/8-28. Do not use regular 1/8 NPT fittings. The top end of the feed line connects to a banjo fitting bolted to the left rear corner of the head where the factory used a 5/16-24 bolt with copper washer to plug a hole drilled for the internal oil channel to the rocker assembly. The banjo bolt included in the kit is the correct 5/16-24 thread to fit the head.