For JB4-tuned turbo cars

Stop reading JB4 logs by hand.

Upload a JB4 datalog and get instant boost, knock, and fuel-trim analysis — with engine-health trends and alerts the moment something flags trouble.

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Sample analysis · 2 WOT pulls

demo_g70_pulls.csv
Peak boost

21.0 psi

Knock events

1

Avg fuel trims

10.9%

Flags

1 crit · 4 warn

critical · knock

Run 1: 1 sudden timing drop (worst 6°) — likely knock with the ECU protecting the engine. Check fuel octane, plugs, and intake temps.

warning · boost

Run 1: boost held 3 psi under target while the wastegate was commanding ~max duty (90%) — the signature of a boost leak (charge pipe, coupler, or intercooler) rather than wastegate calibration. Check for leaks first.

warning · fuel

Run 1: AFR ran leaner than 13.5:1 above 10 psi for 3 consecutive samples (max 13.8:1) — typically enrichment lag during spool; keep an eye on it.

warning · boost

Run 2: boost held 3.6 psi under target while the wastegate was commanding ~max duty (90%) — the signature of a boost leak (charge pipe, coupler, or intercooler) rather than wastegate calibration. Check for leaks first.

warning · fuel

Fuel trims averaged 10.9% at WOT — adding fuel (possible intake leak, weak fuel delivery, or injectors). Beyond ±10% deserves attention.

info · temps

Run 1: intake temps climbed 32° during the pull (peak 132°) — intercooler heat soak. Expect some timing pulled when hot.

Boost vs target (psi)

Ignition timing (°)

AFR & fuel trims

Temperatures (°F)

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datazap shows you the numbers. Auto Tracker tells you what they mean — and keeps the whole build in one place.

Automatic JB4 datalog analysis

Upload a CSV (or pull it from Google Drive) and we detect every WOT pull, then compute peak boost, knock events, fuel trims, and boost-vs-target — and flag the issues automatically. No more squinting at rows on a forum.

Engine-health trends over time

Every log feeds trend charts for boost, timing, fuel pressure, and more — so creeping problems show up as a line heading the wrong way, long before they leave you stranded.

Maintenance with overdue alerts

Schedule services by time or mileage, estimate your current odometer between updates, and get told what's due — and what's overdue — at a glance.

Parts, issues & spend

Track your parts inventory, log open issues, and keep a running tally of what the build has cost you.

Your whole garage

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Catch trouble early

Critical and warning flags surface knock, lean conditions, boost leaks, and heat soak the moment a log shows them — so you can back off before something breaks.

Built for JB4-equipped turbo platforms

Tuned for the cars and the people who run them — technical, data-driven, and serious about their engines.

BMW N54 / N55 / B58Toyota Supra A90Genesis G70 & G80 3.3TInfiniti Q50 / Q60 VR30Alfa Romeo Giulia

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  • Automatic JB4 datalog analysis — runs, peak boost, knock & fuel-trim flags
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Know your engine's health before your next pull.

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