Camshaft Analyzer 1.0 rc

Camshaft Analyzer 1.0 rc is a professional-grade camshaft timing and valve event comparison tool designed for engine builders, tuners, and cam designers. It calculates and visualizes complete valve timing events for two camshafts (Cam A and Cam B) side by side — allowing you to compare duration, overlap, and lift with full crankshaft rotation reference.

The system is based on a Comp Cams-style model using a dual cosp mathematical curve to draw realistic cam lobe ramps. Each intake and exhaust lobe is plotted using true cosine motion instead of linear approximations, resulting in accurate ramp behavior and valve acceleration profiles.

Input Parameters

• Intake / Exhaust Duration @ 0.050″ – main duration used for timing points
• Advertised Duration @ 0.006″ – used to determine the ramp profile (optional)
• Duration @ 0.200″ – defines mid-lift aggressiveness (optional)
• LSA (Lobe Separation Angle) – separation between intake and exhaust centerlines
• Advance (°) – cam advance relative to crank (positive = advanced intake center)
• Lobe Lift – peak lobe lift in inches
• Rocker Ratio – multiplies lobe lift to calculate valve lift

Results and Visualization

The analyzer calculates all valve events in crankshaft degrees using BTDC/ABDC/BBDC/ATDC notation: Intake Opens (BTDC), Intake Closes (ABDC), Exhaust Opens (BBDC), and Exhaust Closes (ATDC). It also determines:

• ICL / ECL – intake and exhaust centerlines
• Overlap @ 0.050″ and Advertised Overlap @ 0.006″
• Valve Lift (Intake / Exhaust)
• @0.200″ Durations for mid-lift comparison

The graph displays all four curves — Cam A Intake / Exhaust and Cam B Intake / Exhaust — over a full 720° crank rotation. The center of the chart (0°) corresponds to TDC overlap. You can zoom into the TDC region or pan freely to inspect the full intake and exhaust cycles. Colored toggle buttons allow you to enable or disable each curve independently for easier visual comparison.

Incomplete or Alternate Data

If your cam card does not specify Advertised Duration @ 0.006″ or Duration @ 0.200″, the analyzer automatically estimates a realistic ramp exponent to preserve physical cam behavior. For Bullet Cams or other manufacturers that list "advertised" duration at 0.020″ lift, you can estimate the equivalent 0.006″ duration by adding approximately 18–22 degrees to the published value. Missing values are not required — they simply refine ramp accuracy.

Practical Use

This analyzer is ideal for comparing two camshafts side by side to evaluate changes in overlap, lift, and lobe center positions. You can clearly see how adjusting advance or LSA shifts intake and exhaust timing relative to TDC, and how it affects valve overlap and potential powerband characteristics. The visual feedback makes this tool valuable for performance tuning, dyno preparation, and cam design verification.

Tip: After changing any input, press CALCULATE to refresh all results and the timing graph. Use the checkboxes below the chart to toggle each curve. This tool is completely local — all calculations run in your browser.