Project “My Fiancée’s” Miata: Part 11 – How to add a Professional Awesome Splitter, an APR Performance Wing, and Improve Your Lap Times

To mount the splitter to the car, we found these slick, quick removable boat deck hinges on Amazon. Using 6 locations, we mounted these hinges to the splitter with 2 on the main frame, 2 on the spurs, and 2 on the leading edge. The hinges were mounted to the car with 2 on the main frame rails, 2 on the front frame rail horns, and then 2 on the tie down locations, within the bumper’s front opening. We used  5/16” aluminum tubing, with ¼” rod ends to allow for some adjustment of the angle and height of the splitter. Lastly, we added another angle aluminum piece to the back edge of the splitter, with two pieces of aluminum extending rearward to lock in the splitter in place after it was adjusted.

With the splitter in place, you can see a hell of a lot of the front tire still. This is bad for drag and lift. Simple tire spats/deflectors go a long way in improving efficiency. Additionally, notice the little splitter fence on the edge of the blade. Not just for looks, these simple fences increase efficiency as well… when done right. A lot of oversized designs you see actually do the exact opposite, hurting overall downforce and increasing drag!


These side spats are actually riveted to a removable bracket that requires just two bolts to be removed.
This simple cable running from the tire spat to the front edge of the splitter end plate helped control flex in our system extremely well. That being said, cables are notoriously draggy for their size. Better solutions exist, but on this build, simplicity won out.

With the splitter mounted, it was easy to see how much the tires extended out of the front bumper and into the freestream of airflow. This is terrible for drag and can create lift where the tire meets the road. We used some simple ABS plastic sheets we had lying around to create tire spats that bolted to the inner bumper and also bolted to the splitter via aluminum angle strips. This had a double benefit of strengthening the outside edge of the splitter, while also keeping the spat out of the way of the tire during cornering. We finally added a cable from the upper edge of the tire spat to the front, far-forward edge of the splitter, one last piece of the puzzle to reduce the chance of rubbing the splitter on the ground under braking or in the corners.


  1. Massive congrats on upgrading your fiancee and your car! It’s nice watching the car progress from girlfriend’s Miata to wife’s Miata.

  2. Congratulations to you and yours, good sir! Looking forward to seeing what you two decided on, I’m sure it will make for excellent reading material!

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