9LR (NA/NB) Quick Release Sturdy Boi and Splitter Install

cinnabeard — Fri, 17 Apr 2026 10:26:16 GMT

Just wanted to walk you through how I installed the 9 Lives Racing quick release version of the splitter and Sturdy Bois on my NA.

A lot of the hardware on their splitter is installed with tee nuts, so make sure that the tee nut is aligned inside the the pre-drilled holes before tightening things down.

After joining the forward and aft pieces of the splitter itself, I began putting on the mounts that will end up being the clipping point of the quick release system. Make sure that these notched cutaways point towards the AFT of the splitter.

On the outsides of the splitter, these little support brackets get installed in this orientation

When you install the bolts that the quick release latches onto, I recommend slapping some Loctite on them thangs so they don't somehow shake themselves loose and you end up running over your splitter.

Those bolts will help you determine how to spread the rails out. You want them AS SPREAD OUT AS POSSIBLE.

Now, because I have an NA, we're going to make use of these dudes to begin installing the Sturdy Bois to the frame.

Now, the part that might make some of you squeemish, but the Sturdy Bois will hit your bumper. At least, they did for me. So, some cutting might be necessary. This is what I did.

Underneath the car, looking up at the frame on either side of the radiator, there will be a couple bolts on each side that will need removed. this is where we're going to bolt our Bois to. In the picture below is my driver side frame just left of my radiator. I put a couple long bolts in there to illustrate the ones you need to remove. These long bolts don't go there, the short ones in the kit do, it's just provide a visual reference. Then there's the spacer (for NAs. NBs can ignore the spacer) kinda sitting in that spot. Then finally, the upper half of the Sturdy Boi bolted in.

The long bolts from earlier are for installing the aft bracket on top of the back side of the splitter, which then slips onto the frame under your steering rack. I forgot to take a picture of that after it was installed (reminder to edit that in later) but this is what the bracket looks like. The bracket has non-symmetric holes, so it shouldn't be too hard to figure out how to install it.

The lower half of the sturdy boy installs with the bolt holes towards the back. You'll want to set your ground clearance height to no more than around 4 inches per 9LR's recommendation. I street drive my car so I put mine close to that. Of course, also keep in mind that your ride height and splitter height will play a huge factor in where their air dam fastens to your bumper, so be sure you understand how that will all fit together and it's where you want the splitter and your ride height to be set to before you go drilling holes in your bumper or something. (Also, side note: I'm sure you've noticed by now if you're installing this yourself, but the bolts that are used to mount the brackets to the splitter stick out a decent amount out the bottom of the splitter. Depending on your situation, you may want to grind them down or install skid pucks or something.)

Now, for the corner stabilizers, this is the solution I came up with. If you have a different solution or idea, I encourage you to try it out. You don't have to do it the way I did. Having said that, the intent of 9LR with this kit is to mount the corner support to one of the holes underneath your headlight housings. Here's a picture of the underneath on the passenger's side without the support in the way, and then a picture of where I bolted mine in.

Since I elected to leave most of my bumper in tact, there was an issue with the bumper being in the way of the support, so... I took a holesaw and eliminated that problem. There's a sort of stiffener in that corner of the bumper (forgot to take a picture of that too, dangit) that has a slot in it. I aligned the holesaw to expose that slot. After connecting everything together, I set blocks under the corners to lift them to the ground clearance I wanted and locked down the sliding pieces of the support. Here's the result:

And that's pretty much the whole install. Hopefully that helps someone! I'm not covering the install of the air dam in this post, but here's my WIP on that

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9LR (NA/NB) Quick Release Sturdy Boi and Splitter Install