Latest news with #RobDahm
Motor 1
05-05-2025
- Automotive
- Motor 1
Rob Dahm's 12-Rotor Engine Made 1,515 HP. Then It Caught on Fire
The saga of the mighty 12-rotor engine continues. Rob Dahm's latest video on the monster mill focuses on more dyno tuning, and there's some good news to share. The engine is indeed a beast, posting four-figure horsepower and torque numbers with ease. Unfortunately, the big rotary set itself on fire in the process. And that's not the only setback in the project. We've been following the progress of this project for a while now. Dahm first got the engine back in 2023; it was built several years ago but in his care, the massive 15.7-liter engine gained not one, not two, but three turbochargers . That's because the rotors are set up in three banks, giving the engine something of a V-shape to it. Before Dahm got his hands on it, the 12-rotor allegedly made 1,400 horsepower and over 800 pound-feet of torque, spinning to over 10,000 rpm in the process. We can confirm it makes at least 1,515 hp and a very stout 1,281.4 lb-ft of torque. We say at least because things are still very much in the testing and troubleshooting phase, as evidenced by the engine catching fire after its power pull. Apparently, it generated so much heat that plastic and fiberglass shielding combusted. It ultimately reached 7,500 rpm–far short of its rumored limit. Surprisingly, it seems the dyno team wasn't immediately prepared for such a situation. Someone is heard asking "do we have an extinguisher or something?" Moments later, a person runs into the room and starts blowing on the engine. Finally, someone jumps in with a fire extinguisher, roughly 15 seconds after the fire started. The damage was relegated to the aforementioned shielding, and after a bit of clean-up, the engine was ready for more testing. That's where things go from bad to worse. Apparently the engine was damaged to some degree during the high-rpm pull, but not due to the fire. A keyway was damaged, causing potential timing issues, and the engine itself became severely flooded from the power run. Back at the shop, a compression test found some rotors down considerably, likely due to damaged seals. Dahm doesn't believe there's any detrimental damage to the engine, but it will need a full teardown to inspect the internals and replace seals. The original goal for this video was 2,000 horses; with a leaner setup (and obviously no fire) it could get there. But we'll have to wait for a future video to see if that goal is ultimately realized. More On The 12-Rotor Engine Listen to Rob Dahm's Mind-Melting 12-Rotor Engine on the Dyno Go Inside The World's Only 12-Rotor Engine Get the best news, reviews, columns, and more delivered straight to your inbox, daily. back Sign up For more information, read our Privacy Policy and Terms of Use . Source: Rob Dahm / YouTube Share this Story Facebook X LinkedIn Flipboard Reddit WhatsApp E-Mail Got a tip for us? Email: tips@ Join the conversation ( )
Yahoo
17-03-2025
- Automotive
- Yahoo
A Turbo Single-Rotor Miata Looks Like The Most Fun An NA Can Get
The Mazda Miata is beloved for being tiny and light, a combination of qualities most modern automakers seem to avoid like the plague. It's never been the fastest car, but who really needs that? It's more of a slow-car-fast deal, and every method of upping the power always seems to add weight in equal measure. Unless, apparently, you're rotary wizard Rob Dahm: then you can slap a turbocharged single-rotor Wankel in there, and add power while actually cutting weight. Dahm's latest project is to swap an NA Miata's four-cylinder out for a compact rotary engine. But unlike other rotary swaps, that usually use a 13b dual-rotor out of an RX-7, Dahm is using just a single rotor for his Miata. This comes with its own challenges around simply putting the engine together, but it also ends up with an engine block that weighs just 64 pounds, or less than half the shortblock weight of the engine it's replacing. Yet Dahm claims, with a properly-sized turbocharger, this build could double the Miata's factory horsepower. Read more: Subaru Had It Right All Along This video is just the first in the build series, but it's already more progress than many ambitious swaps ever make. The Miata's transmission has been cut up and welded to a rotary bellhousing, and the single rotor mill is physically inside the car's body. Surely not for the final time, as it's missing little niceties like "engine mounts," but it's in there all the same. The rest is just wiring and pipes, and that's easy, right? If Dahm is correct about the eventual power and weight of this engine, he could have a truly incredible Miata on his hands by the end of the build. It would be more powerful than any Miata built by Mazda, but still light enough to sit with the stock cars, and not so overwhelmingly powerful to entirely change the beloved driving dynamics of the NA. We'll have to keep our eyes peeled on the build to see how it pans out. Want more like this? Join the Jalopnik newsletter to get the latest auto news sent straight to your inbox... Read the original article on Jalopnik.
