8 min 41 sec

Car Enthusiast Sells DIY Tune-Up Kits

A longtime side hustler creates a series of products for fellow car enthusiasts.
Cars Niche Ideas Product Reselling

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What It's About

A car enthusiast finds a way to shift into drive.

Business Model
Skills Required
Sourcing & Coordination
Profit Potential

Words of Wisdom

The automotive aftermarket is beyond saturated, so it can be hard to get a foot in the door, but if you know your customers well enough and actually care about them, it's not hard to get traction. Dustin says you should start out by solving your own problems because if you don't believe in your own product, no one else will. Treat customers with respect, don't lie to them and always offer tangible proof of any claims you make.

Fun Fact

We have a lot of car enthusiasts who listen to the show, but here is something you may not know—the Ford GT is so strong that during the "Roof Crush" test, it actually broke the crushing machine! Try though they might, Ford didn't have a roof-crushing machine strong enough to crumple even one measly little supercar.

Notes from Chris

Episode 739

Software engineer Dustin Davis has had a lot of side projects. He started at age 13 by selling bootleg software on CD-Roms before broadband internet was common. Then, he had a 10-year hustle doing printer maintenance and repair. For the last 5 years, he hired a guy to do the work. Dustin just created invoices and took a cut.

For his next project, the one we’re featuring here, he looked in a different direction. Specifically, he looked to the race track. As a lifelong car enthusiast, he had recently purchased a brand-new sports car and was out doing laps on the track. He had some trouble shifting gears at high speeds due to drive-train movement caused by weak components used by the manufacturer.

After parking the car in the garage, he spent the next week thinking about how to solve that problem cheaply and easily. There were some existing solutions, but they all came at great expense, difficulty, or resulted in a car that was unpleasant to drive.

  Using materials he got from Home Depot, Dustin was able to build a prototype that would fix the problem. He called it an "Engine Leash" since that's what it looks like, two brackets and a steel cable. One side attaches to the frame and the other to the engine. The Engine Leash solved the original problem with none of the drawbacks of the existing solutions. Best of all, he spent less than $100 on this endeavor and had materials left over to make more.

After testing it out, he posted about it in a car enthusiast forum—and to his surprise, he got a lot of positive feedback. He offered the tool for sale and had a few takers right away. It helped that it was a fraction of the price of any other solution and only took 10 minutes to install.

  Once he had sold enough, he was able to get the brackets laser cut instead of doing it manually himself. This saved a lot of time, increased the quality, and allowed him to produce more units to keep up with demand. Eventually, he didn't need to actively market them, they sold themselves by word of mouth from satisfied customers.

He’s now averaging $4,000-$6,000/month through 3point8 Performance. Before that, he was using Excel to manage everything and it got sloppy, so that figure doesn't include Feb or Mar which were huge months. They also had an $11,000 month in September and a $13,000 month in October.

Dustin’s goal is to end his 20+ year career in technology and move full-time into the automotive industry. He has several new product ideas ready to launch. Right now he’s just trying to find time to work on them.



Inspiration is good; inspiration combined with action is better. Now get back to work!

Yours in the revolution,


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Quote of the Day
"I make a lot more money in my day job, but it’s a thankless job. I don't get to use the stuff I create, and I don't care about it. With the side hustle, I get to enjoy what I do because not only do I do it for myself, I make other people happy, and they want to spend their money with me."
—Dustin Davis #SideHustleSchool

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To infinity and beyond,

Chris Guillebeau