ASO keywords
Most repeated terms in the listing. Highlighted ones also appear in the title.
engine10engines9firing5cylinder4gear4shift4diameter4four stroke3firing intervals3shaft synchromesh3synchromesh transmission3gear ratios3shift forks3cylinder count3firing order3diameter calculated3engine sound3preset engines3stroke3tire3valve3transmission3synchromesh3realistic3
What's new in 1.1.0
Introducing the new “MotionStep” feature, plus a new “VTEC” chapter in TechTour.
We’ve also redesigned the “Engines” sharing site and refined many details throughout Trans4motor R.
■ MotionStep
Tap at any moment to freeze the engine, then step the crank angle forward or backward to take a closer look at the internal mechanics.
While paused, you can still rotate, pan, and zoom the view freely.
■ TechTour
A new “VTEC” chapter has been added, showing how the VTEC mechanism works.
■ Engines
The “Engines” sharing site has been redesigned.
Official engines and user-created engines are now clearly distinguished, and it’s easier to discover official and newly uploaded engines.
New upload rules also let you share more of your engine creations.
■ Editing
Slider controls in the engine editor have been further improved.
While dragging on the slider, values now snap to larger grid increments for quick, coarse adjustment.
Move your finger up or down away from the slider to switch to progressively finer grid increments, making it easy to fine-tune the value you want.
■ Graphs
A crank-angle indicator has been added to the ignition timing and piston position graph, making it easier to follow how they relate to the current crank angle.
■ Other Improvements
• Refined the motion of internal components such as cams and rocker arms
• Improved automatic clutch engagement when launching from a standstill
• Added selectable Normal/Reverse crank rotation for motorcycle engines
• Made the valve angle adjustable across all engine configurations
Released Dec 10, 2025. Current version shipped Oct 14, 2026.
Store description
The definitive successor to the original Trans4motor is finally here — a new installment that lets you freely explore and animate four-stroke engines on your iPad or iPhone.
Created for those who love internal-combustion engines and never tire of their rhythm, mechanics, and beauty.
【Seamless Engine Morphing】
Switch from inline to V configurations, alter bank angles, change cylinder counts, and adjust firing intervals.
Every change transforms the engine while it continues running.
Camshafts split and merge, crank phasing shifts, valve angles move dynamically — a completely new way to experience engines.
【All-New Transmission Simulation】
For the first time in the series, the gearbox itself is fully visualized.
・3-shaft synchromesh transmission
・2-shaft synchromesh transmission
・Dog gearbox (motorcycle-style)
Enter tooth counts manually, or let the app generate realistic gear meshes from gear ratios.
Follow shift forks, constant-mesh gears, clutch engagement, and truly see how power flows.
【Deep Engine Specification Editing】
Greatly expanded from the original, allowing a far richer expression of each engine’s character.
・Cylinder count, bore, stroke
・Bank angle, mounting angle
・Firing order, firing interval
・Cam drive (belt / chain / gear)
・Valve train (SOHC / DOHC / OHV / VTEC / Desmodromic)
・Valve diameter and included angle (reflected in the CG model)
・Tire width, aspect ratio, wheel diameter (outer diameter calculated automatically)
Recreate everything from spirited singles to distinctive 5-cylinder pulses, modern V4 superbikes, and the bold heartbeat of American V8s.
【Realistic Vehicle Physics】
Not just an animation.
Torque curves, vehicle mass, gear ratios, and tire diameter are calculated frame by frame to determine vehicle speed.
Shift through the gears and feel how the engine and drivetrain connect as acceleration builds.
【Connect with the “Engines” Sharing Platform】
Share your creations with the world.
・Upload / download
・Share to X (formerly Twitter)
・Community “likes” and voting
・Planned competitions
Build a community-driven engine library with fellow enthusiasts.
【GearVision Mode】
Gears, shift forks, clutches — see exactly which components are transmitting power at any moment.
A visualized power-flow mode revealing the inner workings of each shift.
【TechTour】
A hands-on learning mode evolved from the series’ interactive tutorials.
・Four-stroke fundamentals
・Firing order
・Synchromesh mechanisms
Engines become even more fascinating when you understand how they work.
【Enhanced Engine Sound】
With support from Sound Design Lab LLC, this latest audio method combines single-shot, harmonic, and random-noise components to create a natural and realistic engine presence.
Differences in cylinder count and firing intervals come through with greater character and detail.
Engine sound is included as a standard feature, not an in-app purchase.
【Preset Engines】
Trans4motor R includes 12 preset engines ranging from classic icons to modern super-sport engines and powerful V8s.
※ For learning and presentation purposes, the engine CG animations run at one-tenth of real-world rotational speed.
※ This app reproduces engines based on publicly available specifications for educational use and is not intended to be an exact replica of actual machinery, dimensions, or designs.
※ Company names and product names mentioned in this app are trademarks or registered trademarks of their respective owners.
See this store page in another country
Prices, ranks and reviews are per country. Revenue above is already worldwide.