NC/ND oil funnel adapter

 Have a favorite funnel, but you're always scared it's going to fall out? Don't like a moving target? Maybe you use Redline oil, so you only kinda need a funnel. This is the tool for you. This mini-funnel threads into the valve cover, so there's no concern of it falling out. You can use it to hold your favorite funnel in place, or you can slip a Redline bottle into it - the inside of the funnel is the perfect fit for a Redline bottle. Either way, you'll have built-in air passages, so there's no chance of the oil burping back out of your funnel. Last but not least, this is 3D-printed in-house out of Onyx - a carbon fiber-infused nylon that's unaffected by engine oils (among other things).

The NC and ND Miatas use a "bayonet" style of threading that we've mostly* duplicated here. *Since we're not using an O-ring (we don't need to tightly seal the funnel), we use notches at the top of the thread. There might be a tiny bit of wobble, but not much, and it's not possible for it fall out. In order to remove it, you'll need to pull up slightly then unthread. 

This is another part from our You Design program, which gives the DIY community an outlet for their designs and an opportunity to make some money from their hard work and ingenuity. This particular design is from Ollie Staples.