Pit Row Dyno: The Complete Package

🏁 Pit Row Dyno: The Open Source Solution for Small Engine Performance

Please note, there is a 2-4 week lead time on this product. Please feel free to reach out for current wait times.

So you got bit by the bug, or you've always been infected. Now you've taken what should be a cheap hobby and thrown piles of dollars at it. You've bought all the parts, crankshafts, connecting rods, the pile of cams and valve springs you've got is taking over the corner they're in. Pistons? You've got those. You tried all of the various ways they can be combined, and have nothing but your seat of the pants dyno to go by, and that thing is dollar biased. Here's the solution, period.

The Pit Row Dyno is the solution—a purpose-built, affordable, and fully digital dynamometer that gives you objective data to perfect your tune.

⚙️ Performance and Engine Fitment

The Pit Row Dyno is designed to meet the demands of the most popular small-engine builds.

• Universal Clone Fitment: Fits Honda GX200/160 and clones like the Predator 212. Any engine that follows the standard 6 3/8" (162mm) base bolt spacing, has a keyed 3/4" shaft (long or short), and has the same crankshaft height as the Honda GX200/160. You know the engines, they're all over the place, and everyone is putting their stickers on them. They ship here from China and are cheap enough to be reigniting a bit of a minibike/go kart revival.

• Dynamic Scaling: All engines are different, and make different power at different RPMs. Maybe you've built something close to stock internally but spins to the moon—the low power/high RPM setting is for you.

  • Maximum Capacity: Up to 40 HP and 10,000 RPM.

  • Precision View: Choose an RPM range (either 0-5000 or 0-10,000) and a HP range (20 HP maximum or 40 HP maximum). These settings affect both the graphs created and the gauges shown, allowing for you to best analyze your power band.

💻 Interface and Testing Modes

The UI is intuitive and easy to navigate, designed for immediate and consistent results.

• 7" 800x480 Capacitive Touchscreen: The large high-res display makes interacting with the Pit Row Dyno a breeze. Even in direct sunlight, the screen is still visible enough to use the machine. The touchscreen and the UI combine to make a simple, easy to understand and navigate, yet powerful design. The real-time analog gauges look great and are easy to read and understand. Who doesn't like watching those needles move?

• Dyno Run Mode: A 10-second guided session that displays step-by-step instructions and times out at the end, ensuring consistent, repeatable pulls for accurate comparisons.

• Freestyle Mode: Stay there as long as you like, make several pulls, and the data is automatically captured and will fill in the chart using the peaks at each RPM point to create a more accurate picture of the power curve. This mode also allows you to spend some time with the machine and get a feel for how to use it. Repeatability really comes down to user error after a while; the more you use it, the more consistent your pulls will become and thereby the data you get from them. (The ugly spot in the one graph shown is where I stalled the engine during the run—you can still see the consistent results.)

🎒 Portability and Open Source Advantage

• Compact Design: Engineered from the beginning with ease of transport and storage in mind. When no engine is mounted the unit occupies a 18"x16"x14" area, with a 16"x16" footprint. You can store it just about anywhere when not in use. You have room for a dyno this size, trust me.

• Ready for Track Day: With a weight of just over 40 pounds, it is heavy enough to take some abuse and sort of hold itself in place through the most brutal of runs (clamping it down is still highly recommended!). That same 40 pounds makes it not too much of a chore to throw in your trunk or the back of your truck when you go over to your buddy's place for track day.

• USB-C Power: To maximize portability, power is supplied via a USB-C port on the touchscreen. This allows the use of any portable battery bank with a USB port to power the unit. (How else could I give it a "batteries not included" notice like all of the favorite things from my youth? Seriously though, not included.)

• Completely Open Source: Everything, from the software running the interface, to the parts list and the complete CAD design of the product is open source. I use and benefit greatly from open-source software and designs, and couldn't sleep at night if you couldn't build your own Pit Row Dyno if you bought all of the parts. Anyone can modify the code, expanding functionality to suit their needs.

• Data Options: Data is sent over USB as well. While the unit logs and displays all you need, the open-source nature means you have the power to write your own desktop software for data logging, viewing, and analysis. I'm saying you've got options. 

• Don't pay me, build it yourself: You can go to https://github.com/notforhire/small_engine_dyno to see if that might be the approach that best suits you.

🛠️ The Origin Story

This whole thing started after an evening in the shop where a buddy and I were debating how much was too much to port out of a head before power dropped off. Ultimately, without any real way of actually knowing, not just going by what some guy on the internet said, I started thinking about a dyno. We have cool tools in the shop, some of them were group buys—how much could they cost? Well, there's a range. It starts high and goes up. This was supposed to be a quick weekend project where I hack something together for cheap. 14 months later, after countless hours in the shop and in front of the computer, and who really knows how many prototypes, and way more money wasted than I ever suspected, I figure I will save you the trouble, maybe recoup a little something out of my investment while we're at it.