V8 Spark Plug Holder

My dad needed a spark plug holder for the race engine so he could inspect them when rebuilding. This is designed to hold 8 NGK plugs, it also has an optional magnet insert where you can pause the print of the base and insert 8x 10x3mm magnets.

I used heat set threaded inserts for the pillars and M4 bolts, but you could always design your own pillars to suit without the threaded inserts and just thread straight into the plastic.

I printed in PLA with the only supports being on the base bolt holes. There is also an arrow so you can arrange the spark plugs based on where they are in relation to the front of the engine.