Dyno Forge

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a browser-based 3D engine-building and dyno simulator titled “Dyno Forge.” The game should open in a dark, stylized Three.js garage/test area: a charcoal-blue floor with a visible measurement grid, deep navy background and fog, a large pit-garage building on the left/back and a small test car on the right/back. In the center, show a compact, orbitable engine assembly made from simple shaded metallic primitives: a gray metal engine block, silver cylinder head, blue intake manifold or orange turbo hardware, green fuel rail/spark-coil details, gray exhaust/header tubes, and pulleys. Use directional shadows, cool industrial lighting, semi-realistic low-poly materials, and a dark neon-accented interface. The engine should visibly rebuild when parts are changed; naturally aspirated induction shows blue intake trumpets, while boosted induction adds one or two orange compressor/turbo forms and pipes. Aggressive race/drag cam choices can use red danger-colored details. Allow mouse or touch dragging to orbit around the engine with damping; include a Fit View button that resets to a whole-engine garage view, Full Screen, and Hide UI/Show UI.

Implement the core loop: the player selects engine parts from categorized cards, the central model updates, calculated performance changes, and the player tunes and runs a dyno. Provide categories/tabs for Block, Internals, Head, Cam, Induction, Fuel, Exhaust, ECU, and Cooling. Each category has selectable part cards showing the part name, a short tradeoff note, and stats; the equipped card is highlighted green and marked INSTALLED, while other cards say INSTALL. Include a broad catalog with the actual kinds of options represented by the game: multiple inline, V, boxer, rotary, diesel, V8/V10/V12, and hybrid-style blocks; cast, hypereutectic, forged, billet, lightweight, stroker, endurance, and drag internals; economy/street/race/titanium or torque/endurance/VVT heads; mild, sport, race, drag, tow, endurance, turbo, and programmable VVT cams; naturally aspirated individual throttle bodies, carburetor, superchargers, turbochargers, and compound turbo induction; pump, regular, E85, race, methanol/ethanol, nitro, and diesel fuels; quiet/header/race/open and turbo-oriented exhausts; safe, sport, track, kill, economy, drift, endurance, and boost-by-gear ECUs; and stock, street, track, ice-tank, air-to-water, and oil-cooler cooling. Parts must be meaningful tradeoffs: displacement/base torque and weight, flow and rpm, low-rpm torque, response, boost/power, lag, heat, fuel/cooling, friction, strength, reliability, and ECU risk.

Include a special “Custom Engine Blueprint” block option. When selected, show controls for layout (Inline, V, Boxer, Rotary), cylinder count from 2–12, bore 60–115 mm, stroke 55–120 mm, material (Aluminum, Iron, Billet), and compression from 7–14. Calculate and display its displacement, base torque, safe rpm range, weight, and a note containing bore, stroke, compression, and material. Changing these controls immediately recalculates the engine and stats.

Show a fixed HUD over the 3D scene. At the top-left display the title and subtitle “Build an engine, run the dyno, chase power without blowing it up.” At the top display four prominent metrics: Peak HP, Torque, Redline, and Reliability percentage. A lower-left parts panel contains the category tabs and scrollable part cards. On the right, show a dark “Dynograph” canvas and a Custom Tune panel. The dynograph has a navy/black graph background, fine grid lines, RPM labels along the bottom, POWER / LB-FT vertically, a red HP curve, a mint-green TORQUE curve, and a yellow vertical RPM marker with its current RPM during a run. Include the bottom readout “Stress [number] / Strength [number] · Knock margin [number].” Above/around the graph identify HP and TORQUE in matching red and green colors and label the RPM scale.

The dyno graph should plot calculated points from idle RPM to the selected rev limit in 200-RPM increments. Calculate a mechanical redline from the chosen block, internals, head, cam, and exhaust, then clamp the tunable redline between 3400 and 11000 RPM. Performance should derive from displacement/base torque, part response/friction, head and exhaust flow, cam duration, induction boost/power/lag, fuel factor, ECU timing/air-fuel factor, cooling drag, heat load, knock margin, over-rev, and stress versus strength. Report peak horsepower and peak torque plus the RPM at which each occurs. Higher boost, timing, rev limit, flow, and aggressive parts can improve output but raise heat/stress and reduce reliability; better fuel and cooling can improve knock/heat margin. Display a readout naming the selected block, induction, and ECU, with HP@RPM, TQ@RPM, boost, and either a warning such as “Risky tune: lower boost/timing/rev limit or add cooling/fuel” when reliability is low or a balanced-tune message.

The Custom Tune panel must contain live range sliders for Timing (-8 to +12 degrees, 0.5 steps), Boost (-6 to +10 psi), Fuel (-12 to +18 percent), Rev Limit (3500–10500 RPM in 100-RPM steps), Cam Gear (-8 to +8 degrees), and Idle (700–1500 RPM in 50-RPM steps). Show each current value beside its label and immediately update the engine stats and graph whenever a slider changes. Include a prominent orange/red RUN DYNO button and a blue/mint RANDOM BUILD button. Run Dyno should animate a left-to-right graph reveal over time, display a moving yellow RPM marker, and subtly vibrate/bob the 3D engine during the pull; once complete, leave the full graph visible. Random Build should randomly install one part from every category, reset the custom tune offsets to zero (and idle to 900), set the rev limit to the mechanical redline, and refresh the model, HUD, and graph.

Make the layout responsive. On desktop, show parts at lower left and graph/tuning/actions at lower right. On narrow screens provide rounded PARTS, DYNO, and TUNE view buttons so the large parts list and graph/tuning panels do not obscure one another: Parts shows the category/card list, Dyno shows the graph and actions, and Tune shows the sliders and actions. Keep the dark translucent panels, blue/green/orange/red accents, rounded cards, condensed display typography, and readable compact metrics. Expose game state functions window.getGameState() and window.setGameState(patch), including selected parts, custom engine settings, tune values, calculated summary stats, dyno running/reveal/run count, and camera position, so an external controller can inspect or patch the build.