Perhaps you’ve heard about Rob Dahm’s remarkable 12-rotor engine featuring three turbos? This is somewhat the opposite. It’s his single-rotor Miata, which he has been constructing and showcasing on his YouTube channel for approximately the past year. Dahm recently tested it on the dyno, and the outcome was surprisingly impressive. In fact, it’s wild enough to damage the rear differential if pushed hard enough.
This project has been one of the most exciting to follow on YouTube lately. You could invest hours watching all the one-rotor videos, but the key takeaway is that the engine is crafted almost entirely from billet aluminum, tipping the scales at around 70 pounds. A Garrett GBC-22 turbo with an internal wastegate boosts its performance, and it features a 3D-printed intake manifold since you can’t just find those available anywhere.
Dahm has been piloting the single-rotor Miata through the last five episodes. Tuning it has been a laborious endeavor, requiring significant effort to refine the engine’s performance and behavior. It continues to inject a substantial amount of fuel into the combustion chamber, but progress is being made.
Upon entering Westech Performance, the team secured the Miata for a round of test runs. It achieved a peak result of 155 horsepower and 136 lb-ft of torque, which is impressive considering this is a fully custom-built project with minimal displacement. The one-rotor engine could potentially produce even more power once Dahm resolves the ongoing fuel problem.
Turbo 1 Rotor Miata on the Dyno!
In the end, this build isn’t fully refined, but it’s certain to be soon enough. Dahm has a solid understanding of the issues, with internal wastegate boost creep resulting in sudden surges up to 22 psi that seem to be pushing fuel into the oil catch can. Once he fine-tunes the clearances and gaps within the engine and resolves the turbo challenges, it should emerge as a robust performer.
I admire it in any case. I could never assemble something like this, and honestly, who cares about the power output? A working turbo one-rotor is remarkable. The fact that it can drive a Miata dashing down the road is just an added bonus.
Have a tip or inquiry for the author? Reach out to them directly: [email protected]
### Acoustic Profile of a One-Rotor Turbo Miata Generating 155 HP
The Mazda Miata, celebrated for its lightweight construction and nimble handling, has historically been a favorite among automotive enthusiasts. When upgraded with a one-rotor turbo engine delivering 155 horsepower, the acoustic profile of this vehicle evolves into a distinct sound journey that embodies the essence of rotary engines while preserving the Miata’s lively spirit.
#### Engine Features
A one-rotor engine, typically derived from the Mazda Wankel rotary framework, functions differently than conventional piston engines. It consists of a triangular rotor moving within an epitrochoidal casing, forming three unique chambers that facilitate intake, compression, combustion, and exhaust operations. This architecture enables a seamless power delivery and a unique auditory signature.
#### Acoustic Profile
1. **Idle and Low RPMs**: When idling, the one-rotor turbo Miata produces a deep, throaty growl typical of rotary engines. The sound is less fierce than a multi-rotor setup, providing a more muted yet captivating auditory sensation. As the engine revs to around 2,000 RPM, the noise becomes more pronounced, featuring a distinctive whirring quality that tends to be described as a blend of a small displacement engine and a turbocharged roar.
2. **Mid-Range RPMs**: Reaching mid-range RPMs (about 3,000 to 5,000 RPM), the acoustic profile intensifies. The turbocharger begins to spool, introducing a notable whoosh as it pushes air into the combustion chamber. This is paired with a higher-pitched, raspy exhaust note that is both thrilling and unmistakably rotary. The sound is often compared to that of a high-revving motorcycle, with a clarity that invigorates the senses.
3. **High RPMs**: At elevated RPMs, generally above 6,000 RPM, the one-rotor turbo Miata delivers a stimulating climax. The exhaust note escalates, generating a symphony of mechanical sounds that integrates the high-pitched whine of the turbocharger with the iconic rotary engine’s “buzz.” This peak performance sound showcases the engine’s capabilities, demonstrating its ability to rev freely and deliver power effectively.
#### Exhaust System Impact
The acoustic profile of the one-rotor turbo Miata is largely shaped by the exhaust system. Aftermarket exhaust solutions, such as cat-back systems and resonators, can enhance or alter the sound. A well-crafted exhaust system can boost the turbo’s whoosh while imparting a richer, more aggressive tone during acceleration. Factors like materials, pipe dimensions, and muffler designs all play significant roles in defining the overall sound experience.
#### Performance and Acoustic Interaction
The sound of the one-rotor turbo Miata is more than just an auditory delight; it adds to the overall driving experience. The engine’s sound offers feedback to the driver, indicating power delivery and performance traits. The engrossing sound can enhance the enjoyment of driving, making each acceleration feel more dynamic and connected.
#### Conclusion
The acoustic profile of a one-rotor turbo Miata generating 155 HP is an enthralling mixture of distinctive rotary traits and turbocharged exhilaration. From the low rumble at idle to the electrifying high RPM peak, the auditory journey is a crucial aspect of what makes this modified Miata an exciting vehicle. Enthusiasts value not only the performance but also the unique sound that differentiates it from traditional piston-engine sports cars.
admin