# Trans4motor R — Engine Transmission Simulator

> Interactive simulator for designing, animating, and understanding internal-combustion engines and transmissions. (iPhone/iPad app by Kitt Peak, Inc..)

- Source: https://appshunter.io/ios/app/trans4motor-r/id6739180076 (this page in markdown: same URL + `.md`)
- Developer: [Kitt Peak, Inc.](https://appshunter.io/developer/399507326)
- Category: Education
- Price: $7.99 (on sale, was $9.99)
- Rating: 4.40/5 from 7 App Store ratings · 22 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.0 · 174 MB
- Languages: American English, Japanese
- Released: 2025-12-10
- Data updated: 2026-09-07
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/trans4motor-r/id6739180076/reviews.md

## What is Trans4motor R?

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.

## Key features

- Seamless engine morphing (inline to V, cylinder count, firing intervals)
- Full transmission visualization (3-shaft, 2-shaft, dog gearbox)
- Deep engine specification editing
- Realistic vehicle physics simulation
- Community sharing platform for engine designs
- Interactive learning modes (TechTour)
- Enhanced, realistic engine sound simulation

## Recent user reviews (10 of 22)

All indexed reviews: https://appshunter.io/ios/app/trans4motor-r/id6739180076/reviews.md

### 3/5 — 単気筒OHVだとカムシャフトがシリンダーに埋まる

*2026-08-12*

タイトル通りです。これは私の設計が悪いのかバグなのか分かりませんが、とにかく設計が破綻してしまいます。よろしくお願いします。

### 4/5 — アップデートによる今後の進化に期待

*2026-08-10*

点火時期調整によるサウンドの変化や、精巧な3D表示には脱帽です。
一方で、もう一声…！と思う点もございます。
例えば、必要以上に車重を稼がないと100km/hまでの加速が不自然なほどもたつく(タイヤサイズに関係なくTRCが介入する感覚)現象や、設定した最高回転数までエンジンが回らない現象等があります。
また、ユーザーが編集できる性能曲線等を追加や、車両のCd値の調整機能、タイヤのグリップ力の調整機能などを追加いただければ、多種多様な出力特性のエンジンやクルマが作成可能になる と期待しております。

お忙しい中ですが、お目通しいただけますと喜びます。

### 5/5 — ターボやスーパーチャージャーも実装して欲しい

*2026-07-21*

めっちゃいいアプリだったので課金しましたー！

でもターボやスーパーチャージャーも実装して欲しいなと思いました。

### 1/5 — Needs work

*2026-05-25, version 1.0.5*

It has nothing to do with actual building

### 2/5 — インテグラのエンジンが…

*2026-02-06*

1998ccインテグラTYPE_Rのゲーム内では5速ミッションになっているのですが
実車は6速ミッションですし、エンジンは9000回転まで回ります。修正してください。

**Developer response:** ご指摘ありがとうございます。
エンジン共有サイトのデータをご利用の場合、公式データに加えて有志の皆様が善意で公開してくださるデータも多く、設定が実車スペックと異なる場合がございます。立ち上げたばかりの共有コミュニティですので、差し支えなければ、今後の成長を一緒に見守っていただければ幸いです。

実車同様の「6速／9000rpm」などの情報をお持ちの場合は、編集画面の「最高回転数」および「変速機／ギア数」より数値の調整も可能です。

設定方法にご不明な点がございましたら、公式ページの「取説・ヘルプ」をご参照されるか、「お問い合わせ」からご質問ください。引き続き「Trans4motor R」をよろしくお願いいたします。

### 5/5 — Yahhhhh

*2026-01-23, version 1.0.4*

This game is so much better than the first one I played it for hours without getting bored you guys are amazing developers, but I asked one thing make me able to like add turbos and superchargers to my engines that would make it top-tier

### 4/5 — バグ対応は早い

*2026-01-21*

初期バージョンは本当に酷かったですが、不具合が少しずつ改善されている点は評価できます。

点火時期設定などをスライダー／ボタンだけではなく文字入力できる様にして欲しいのと、ミッションの段数変更（9速ATミッションなど）ができるともっと良いと思います

**Developer response:** ご意見を頂戴しました。ご不便をおかけし申し訳ございません。ご指摘の「点火間隔」「最高回転数（レブリミット相当）」については修正・機能追加を行い、v1.0.1 として現在App Storeで公開済みです。
また数値調整は、スライダー左右の「＋／－」ボタンで最小単位で変更でき、長押しで連続変更もできます。ぜひアップデートしてお試しください。

### 5/5 — Thank you guys so much!

*2026-01-16, version 1.0.4*

I absolutely love this game and its improvements from the original game. In the original, all of the engine sounded like vacuum cleaners lol. But now, changing engine dynamics actually change the way engines sound! Thank you guys.

Hello, this is an edit from the original review, and all I ask is one more feature. It’s more of an aesthetically active feature rather than an actual performance fix, but I wish the ability to change the intake and exhaust orientation on syncromesh mounted engines. The option still exists on the screen, but does not affect anything when toggled. Another note, I WOULD ADORE if you guys added diesel engines (at least for I3, I4, I6, and V8). And 2 strokes up to 4 cylinders. That aside, I see myself buying more games from you guys in the future with production quality of this manner.

### 5/5 — Thank you guys so much!

*2025-12-31*

I absolutely love this game and its improvements from the original game. In the original, all of the engine sounded like vacuum cleaners lol. But now, changing engine dynamics actually change the way engines sound! Thank you guys.

**Developer response:** Thank you so much for supporting Trans4motor since the original version—and for leaving the first review in the US for Trans4motor R!

We laughed at the “vacuum cleaner” comment—we know exactly what you mean. In Trans4motor R, we rebuilt the sound so it reacts to engine settings and dynamics, and we’re truly happy you can hear the difference.

Thanks again, and we’ll keep improving the app with future updates!

### 3/5 — 楽しいけどあと一歩

*2025-12-29*

自分の車をシュミレートしてみました。
結構楽しいんですが

バルブ径が25mm以下を設定出来ない
過給の有無や種類が設定出来ない
6速ミッションでうちの車はギヤ比設定拒否されました
仕方ないので5速まで入力してます
車重が設定出来ないので小排気量だと1速の繋ぎが重すぎる
バルブ数が設定出来ずDOHCだと4バルブだけみたい

などなどいくつか不満点が出てしまいました。

欲を言えば横置きFFの駆動系グラフィックも欲しいかな･･･

まだ1時間ほどいじっただけなのでもう少し頑張って
歴代乗り継いできた車を全てシュミレートしてみたくなりました。
SOHC4気筒12バルブとか出来るかな？

**Developer response:** レビューありがとうございます。
バルブ径の最小値は次回アップデートで、車重についても内部パラメータはあるため、ユーザー様が設定できるようにいたします。

「6速ミッションでギヤ比設定が拒否された」件は、ギア比→歯数の自動算出が条件によって成立しない場合があります。まず「シンクロメッシュ2軸」でもお試しください（横置きFF等では2軸構成のケースもあります）。それでも再現する場合は、公式サイト上部の「お問い合わせ」から、車種/年式、最終減速比、各段ギア比（6速分）をお送りください。いただいた情報を元に算出ロジックの改善に活かします。

他のご要望も今後の拡張テーマとして検討いたします。引き続きよろしくお願いいたします。

## Frequently asked questions about Trans4motor R

### What is Trans4motor R?

Trans4motor R is an interactive simulator that allows users to explore, design, and animate four-stroke engines and transmissions. It offers detailed customization for engine specifications and realistic vehicle physics.

### What kind of engines can I simulate in Trans4motor R?

You can simulate a wide range of engines, from single-cylinder engines to V8s and V4 superbikes. The app allows you to alter cylinder count, bank angles, firing intervals, and more to create diverse engine configurations.

### Does Trans4motor R have ads?

No, Trans4motor R does not contain advertisements. It is a paid application, and all features are available without interruption from ads.

### What transmission types are supported in Trans4motor R?

Trans4motor R supports several transmission types, including 3-shaft synchromesh, 2-shaft synchromesh, and dog gearboxes (motorcycle-style). You can manually enter tooth counts or generate realistic gear meshes.

### Can I share my engine creations with others using Trans4motor R?

Yes, Trans4motor R features a community sharing platform where you can upload and download engine designs. You can also share creations to X (formerly Twitter) and engage with a community of fellow enthusiasts.

### How does Trans4motor R help with learning?

The app includes a 'TechTour' mode, which offers interactive tutorials on four-stroke fundamentals, firing orders, and synchromesh mechanisms. This hands-on approach makes understanding engine mechanics more engaging.

### What devices is Trans4motor R compatible with?

Trans4motor R is designed for Apple devices and is compatible with both iPhone and iPad. It requires iOS 4+ and is available for purchase on the App Store.

### How often is Trans4motor R updated?

The app was last updated on February 9, 2026, to version 1.0.5. This indicates a commitment to ongoing development and improvements.

## Version history (last 5 releases)

### 1.0.5 — 2026-02-09

SOHC 2-valve engines now support multi-cylinder (3+) simulation.
Added Port Layout setting: Reverse-flow / Cross-flow (e.g., DATSUN L28).
Added Double-row Timing Chain.

We’ve also published new SOHC examples on the Engine Sharing site:
• NISSAN / DATSUN: Fairlady Z(280Z/S30) / L28 (Reverse-flow)
• BMW: 2002 ti / M10 (Cross-flow)
Download them and start using them right away.

### 1.0.4 — 2026-01-12

Supports SOHC4 (single-cam, 4 valves per cylinder) engines (e.g., HONDA BEAT).
Added new settings: Curb Weight / Gear Count / Exhaust Side / Crank Direction.
Expanded the minimum valve diameter from 25 mm down to 12 mm.
Added Grip to Throttle Mode (Pedal / Grip) — motorcycle-style throttle (tilt toward you to open).

We’ve also published an SOHC4 example on the Engine Sharing site:
• HONDA: BEAT
Download it and start using it right away.

### 1.0.3 — 2025-12-31

Support for longitudinal 2-cylinder motorcycle engines (Moto Guzzi / BMW Boxer, etc.)
Added an engine orientation setting (FR/FF, etc.)
Improved fine adjustment with sliders

Sample longitudinal 2-cylinder bike engines are now available on the engine-sharing site:
• OHV: Moto Guzzi / 850 Le Mans
• DOHC: BMW / R nineT
Download and use them right away.

Slider controls: while dragging, move your finger up/down to enter fine-tune mode—the farther you move away, the finer the adjustments.

### 1.0.2 — 2025-12-19

Urgent crash fix. We have resolved a crash issue caused by the automatic gear-tooth calculation feature (converting gear ratios into tooth counts). Under certain conditions where the calculation was not possible, the app still allowed the data to be saved, which could lead to crashes.
We sincerely apologize for the inconvenience.

### 1.0.1 — 2025-12-16

・Added a “Max. RPM” setting (up to 18,000 rpm!)
・Fixed an issue where some settings were not saved

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## More apps by Kitt Peak, Inc.

- [Trans4motor - Engine Simulator](https://appshunter.io/ios/app/trans4motor-engine-simulator/id899277186)
- [Trans4motor S](https://appshunter.io/ios/app/trans4motor-s/id1561448237)
- [Endless PiP](https://appshunter.io/ios/app/endless-pip/id1617492426)
- [Prism4music](https://appshunter.io/ios/app/prism4music/id6504075908)

All apps by Kitt Peak, Inc.: https://appshunter.io/developer/399507326

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-07.*