Read the log like your tuner would.
Upload a dyno or street pull, and get knock, AFR, and heat-soak issues flagged in plain English — with charts, a PDF report, and AI-suggested fixes.
Upload a dyno or street pull, and get knock, AFR, and heat-soak issues flagged in plain English — with charts, a PDF report, and AI-suggested fixes.
Dyno Log Forge is a free browser-based tool for analyzing ECU data logs from popular tuning platforms including HP Tuners VCM Scanner, EcuTek, RomRaider, and Cobb Accessport. Upload your CSV log file and instantly get:
No installation required. All processing happens in your browser — your log files are never uploaded to any server.
A dyno log (or ECU data log) is a CSV file recorded by your tuning software during a dyno run or street pull. It captures engine parameters like RPM, boost pressure, AFR, knock counts, and timing at high frequency. Analyzing the log lets you and your tuner identify unsafe conditions — like lean AFR, excessive knock, or timing pull — before they cause engine damage.
Dyno Log Forge supports CSV exports from HP Tuners VCM Scanner (including dual-header format with kPa MAP and °F temperatures, which are auto-converted), EcuTek, RomRaider, and Cobb Accessport. Any generic CSV with standard column names for RPM, boost, AFR, knock, and timing will also work.
AFR stands for Air-Fuel Ratio — the ratio of air to fuel in the combustion mixture. A stoichiometric (chemically perfect) AFR for petrol is 14.7:1. On a boosted engine under full load, a safe AFR is typically between 11.0 and 12.5:1 (rich). Values leaner than 13.0:1 under boost are flagged as potentially dangerous. Dyno Log Forge highlights any lean events in your log so you know exactly when and at what RPM they occurred.
Knock (also called detonation or pinging) is uncontrolled combustion in the engine cylinder. The ECU detects it via a knock sensor and pulls ignition timing to protect the engine. Occasional low-level knock counts can be normal, but repeated or high knock events — especially at peak power — can cause serious engine damage. Dyno Log Forge flags runs with elevated knock counts and shows you exactly which RPM band they occur in.
Heat soak occurs when your intake air temperature (IAT) rises — typically after a hard run or in stop-and-go traffic — reducing air density and causing the ECU to pull timing for safety. Most ECUs start pulling timing above 40–45°C IAT. Dyno Log Forge monitors your IAT trace and flags runs where heat soak may have affected results, so you can make back-to-back run comparisons more reliably.
Yes — you can upload up to 3 CSV log files at once. Dyno Log Forge overlays all runs on the same charts so you can directly compare boost curves, AFR, timing, and knock between a before and after tune, different fuel blends, or different ambient conditions.
After your log is analyzed and any issues are flagged, you can request AI-powered fix suggestions. The AI reads your specific flags — lean events, knock counts, IAT levels, timing pull — and gives you plain-English advice on what to tell your tuner, what parts to investigate, and what free checks to do yourself. Free accounts include 3 AI suggestion uses.
Yes. Your CSV log files are processed entirely in your browser using JavaScript — they are never uploaded to our servers. Only the text summary of flagged issues (not your raw log data) is sent to the AI when you request fix suggestions.