ET Engine Beta Guide

Start Here

What this is: a weather-smart ET predictor that learns your car. You give it today's air and your passes; it gives you a predicted ET, a suggested dial, and — over time — proof of how accurate it's been.

Open the ET Engine →

1First 5 Minutes — See It Working

1. Open the app and scroll to Race Report & Analytics.
2. Tap 🏁 Load Example Race Day. A full 8-pass day at Western Colorado Dragway loads — charts, predictions, the works.
3. Poke around: the report, the confidence bar, the DA ladder, the Live Data Map. This is what the app looks like after one real race day.
4. When done: Run Log → Clear All to wipe the example.

The example is safe — it refuses to load if you have real runs logged or sync connected.

2One-Time Setup (per car, ~1 minute)

1. Combo Setup → Induction: pick what feeds the engine (NA gas, NA methanol, nitrous, boosted…). This sets how much bad air actually hurts your combo.
2. Combo Setup → Distance: 1/8 or 1/4 mile.
3. Weather Station → Elevation: your track's elevation (Western Colorado Dragway ≈ 4,660 ft) — only needed if typing weather by hand; the fetch fills it automatically.
4. Optional but worth it: Combo → Advanced → Track Heading — the compass direction the car travels. With it set, fetched wind automatically splits into headwind/tailwind. No more guessing at the flags.

Baseline? Don't worry about it — your first logged pass becomes the baseline automatically.

3The Race-Day Loop

The whole app is this cycle — it's printed across the top of the screen:

1. Get today's air. Type the track name and tap Fetch Weather, or tap 📍 My Location at the track. Temp, humidity, barometer, elevation and wind fill in — and the app jumps straight to your predicted ET.
2. Read the prediction. Predicted ET, suggested dial, confidence. That's your number for the round.
3. Run the pass, then log it. Type the ET (or scan the slip — see §5) and tap Log Run @ Current Air. The app instantly tells you how close its call was.
4. Repeat every round. Re-fetch weather before each pass — air changes, and re-fetching is one tap. Every logged pass makes the next prediction sharper.

4Reading the Prediction Card

• The big number — predicted ET in today's air, blended from two models: physics (your baseline corrected for the air) and your car's own trend line (once you've logged 3+ passes across different air). Tap "How these two models work" on the card for the plain-English version.
• Suggested dial — the prediction rounded up to the next hundredth, so the car doesn't break out.
• ± band — honest uncertainty. Inside that window is a coin flip; don't bet the stripe on thousandths the band can't support.
• The "why" line — always explains the number: "Air is 1,600 ft better than your baseline — worth about −0.20."
• Confidence bar — 0–100% with the exact reasons (+ live weather, − gusty wind…). Swing factors underneath list what could move the number either way, with real magnitudes.
• Better / Same / Worse tiles — today's air vs your baseline pass at a glance.

5Logging Passes

Type it (5 seconds)

ET is the only required field. MPH and 60-ft are optional but valuable — MPH separates power problems from traction problems, and 60-ft tells you if the launch is costing you. Notes field for lane, tune, tires.

📷 Scan the time slip

Tap 📷 Scan Time Slip, photograph the printed slip (flat, good light, fill the frame). ET, MPH and 60-ft pre-fill automatically — always check them against the slip, then Log Run. First scan downloads the reader (~15s, needs signal). Reaction time and incremental times are ignored automatically.

Re-logging at new air

Tap Log Run with an empty ET and the app offers to reuse your last ET at today's air — handy when you're testing how the air alone moves the number.

6Multiple Cars & Drivers

Top of the app: the Car / Driver selector. Each car keeps its own runs, baseline, combo and notes — weather is shared, because the air is the same for the whole pit.

1. + New Car → name it ("Jr Dragster — Emma"). It starts clean.
2. Set that car's combo (§2), log its passes.
3. Switch cars anytime — one tap, instant, nothing is lost. The prediction card shows whose number you're looking at.

7Loading Past Runs in Bulk (CSV)

Got a logbook? Enter a whole season at once:

1. Run Log → CSV Template — downloads the format.
2. In Excel/Sheets: one row per pass — date, ET, MPH, 60-ft, and that day's temp/humidity/barometer (each row carries its own weather — that's what keeps the math honest).
3. Import CSV. The app computes each pass's density altitude, skips bad rows with reasons, and ignores duplicates.

Three or more passes across different air and your car's trend line lights up immediately.

8Planning & Reports

What-If Planner

Test tomorrow before it happens: tap a preset (🌙 Evening cool-down, +10°F, 💨 +10 mph headwind) or type any scenario — see the ET, dial and delta without touching your live inputs. "In that air the car picks up 0.116 — plan the dial DOWN or it breaks out."

DA Ladder & Sensitivity (Quick Reference)

Two live cheat-sheets: your dial at −1,000 → +1,000 ft of density altitude (air improves through the evening → your dial walks down the table), and what ±10°F, humidity, baro and wind each cost your combo.

Race Report & Analytics

Tap Generate Race Report any time: session summary, predicted-vs-actual charts, findings ("your car slows 0.090s per 1,000 ft of DA"), coaching on what to work on, a race-ready checklist, and your crew notes. Copy Report as Text to text it to anyone.

Live Data Map

Every variable in the engine, live, in the order it flows — inputs → air math → models → output. Hold any tile for what it means. Watch a temperature change ripple through to the dial.

9Sync Across Phones + Data Safety

Cloud Sync (team code)

1. On ONE phone: Admin Journal → Cloud Sync → Create Team Code.
2. Copy the code, paste it on each other phone → Connect.
3. Done. All cars, runs, notes and feedback stay in step — changes push automatically a few seconds after you make them.

Backups

⬇ Backup Everything saves the whole app (all cars) to one file. Do it after every race day — takes two seconds, and ⬆ Restore brings it all back on any device.

Updates

If you keep a tab open for days, a blue ⟳ New version ready pill appears when the app has been improved — one tap updates you. (We ship improvements constantly during beta.)

10Beta Testing — What We Need From You

1. Use it for real — every pass, every round, starting with the July 25 race at Western Colorado Dragway. The accuracy column is the whole test: is the engine's call inside the ± band?
2. Scan real time slips — the scanner has only seen practice slips. If it misreads yours, note what it got wrong (and keep the slip).
3. Try to break it — weird inputs, fast switching between cars, dead-signal areas, old tabs. Whatever you find, we want it.
4. Tell us everything — the Beta Feedback box at the top of the app (tap to open): your name, what worked, what didn't, what's confusing, what's missing. Every entry is saved and reviewed.

Known beta limitations (honesty section)

• Fetched weather is a forecast-model reading (~15 min updates) — great for trends; a trackside weather meter still wins for money runs. Every fetched value stays editable.
• The slip scanner needs internet for its first use and hasn't met your track's print format yet.
• Predictions need 3+ passes across different air before the trend line kicks in — the app tells you exactly where it is on that ("2/3 runs", "waiting on air variety").
• Track temp affects the tune more than the air — the engine logs it but only models it once you set a coefficient (Combo → Advanced).

Open the ET Engine and start →