Research an engine AI research with linked sources ↗
Start with your engine.
AI ENGINE RESEARCHApplying replaces the engine inputs and clears the routing measurements. Missing values stay blank. Estimates remain editable.
Header Lab.
Example loaded: VMAX 1700 with custom cam and design assumptions. This is a demonstration, not a stock cam specification.
AWAITING INPUTSFront pipes, rear pipes and the two secondaries each share their dimensions. Left/right is from the rider’s seat. Crossing lines are not junctions.
Routing notices
Engine setup & advanced calculations Measurements, assumptions and comparisons
Measured ports & detailed dimensions
Enter front and rear measurements separately. Port exit ID is the exhaust opening, not the engine cylinder bore.
Front cylinders
Rear cylinders
Secondaries & collector
The diamond marks Recommended. Click its label to follow the calculated target again. Recommendations are starting points from the sheet; check port fit and packaging. For unequal primaries, the secondary target is a shared-path compromise.
Engine & cam timing
Target RPM and EVO drive the tune length. Use the same checking height for all cam timing.
EVO = duration ÷ 2 + exhaust centerline − 180°.
Wave & flow assumptions
Gas temperature sets the volume estimate; mean wave speed is a separate effective assumption.
Sheet comparison settings
Editable design assumptions from the VMAX sheet. Area ratios reference the average area of one selected primary. Enter intake duration at the engine's checking height.
Design details & shorter-pipe options
FR / FL / RR / RL identify front right / front left / rear right / rear left, viewed from the rider’s seat. Each bank shares its entered dimensions. Line crossings are not junctions. Pairing is a routing choice; confirm it against measured firing events. Bend radii and clearances remain illustrative.
Need a shorter primary?
Compare return orders at your target RPMChoose a return to update the target lengths. Manually entered lengths stay fixed; use “Reset lengths” to follow the new target. Higher returns imply more wave travel and uncertain losses. A length fit does not predict power.
Live response
Chase the returning wave.
Enter valid four-cylinder geometry to explore its timing and flow.
Below zero: early. Above zero: late. Slide a length to move its TDC crossing along the RPM axis.
See the diameter effect Mean flow at your target RPM
Travel time uses your fixed wave speed. Diameter changes the mean-flow estimate, not that speed. Playback repeats a travel-time marker; it does not simulate pressure, wave sign, firing order or power. Cone regions are already included in entered paths.
02 / Choose the tube
Three ways to size a primary.
Independent screening rules from the sheet. The flow comparison adds approximate fuel mass to the existing volume model. These are not guaranteed torque or power peaks.
Compare available tube stock
| OD · mm | ID · mm | Torque index · rpm | Mean flow · m/s | Bell + 2% |
|---|
After the first merge
Added path lengths include the intervening merge region. Cone envelopes and stock sizes are approximate; do not add their lengths to the tuned path a second time. Unequal tube bundles need a measured collector layout.
03 / Follow the wave
Where does the return arrive?
Crank angle after each cylinder's firing TDC. R1, R2… mark calculated travel times. The model does not determine wave sign, amplitude or cross-talk; later returns are not guaranteed scavenging waves.
Original wave & mean-flow calculation
Common port allowance and original air-volume model. Routing above uses your individual port paths and the selected stock. Collector area continuity here differs from the sheet's adjustable area ratios.
Wave-speed sensitivity with the remaining common inputs held fixed; not a power curve.
What the sheet adds · assumptions & sources
The VMAX method adds Bell and 88,200 diameter comparisons, stock selection, port matching, secondary paths, collector envelopes and wave timing. This workbench adds separate front/rear measurements and packaging checks.
Compression-based wave-speed correction, dynamic compression and automatic firing-order pairing are not applied. Bank angle alone does not establish firing order, and returning waves are not always suction waves.
All outputs are simplified four-stroke estimates. Confirm cam timing, measured port sizes, routing, firing events and performance before fabrication.
The loaded example retains its custom 256° exhaust duration and 105° centerline. It is not the 933 card or a stock-cam preset.
Explore the intake & exhaust simulator →