LS/VTEC Build — Tuning Dashboard

01Project-Wide Metrics

Aggregated across all 32 logs analyzed over the eight-day tuning window.

Logs analyzed

MSL + MLG, 4 formats decoded

6.8h

Logged runtime

1,490,323 total records

951

Final idle RPM

±48, target 900

Stall events (project total)

concentrated in days 3–5, plus 3 crank attempts day 8

Session Idle Speed & Stability Trend

Hover over data points to view exact session metrics and notes in real time.

Session-wide idle mean and standard deviation, averaged per day. Pooled across every log in a day rather than a single best segment — this is why it differs from the narrower ±48 RPM figure quoted for the final validated run.

Where the build stands today The car starts, idles at target with tight stability, holds coolant temperature under load, charges correctly at 14.1–14.3 V, and has completed multiple road tests. Every remaining blocker is hardware, not calibration — see the final report below.

02Browse by Day

Each day below has its own page with full log-by-log data, real statistics computed from the raw files, and the narrative of what was found and fixed.

Day 1

Aug 8-9, 2026

First Contact & Baseline Review

3 logs 14m logged 1612 avg RPM 2 stalls

Day 2

Aug 9-10, 2026

The IACV Investigation

3 logs 20m logged 1173 avg RPM 8 stalls

Day 3

Aug 11, 2026

Trigger Offset Bracketing

3 logs 44m logged 1289 avg RPM 20 stalls

Day 4

Aug 12-13, 2026

MLG Format Cracked, Cooling Bleed Begins

5 logs 63m logged 1649 avg RPM 0 stalls

Day 5

Aug 13-14, 2026

Polarity Correction & the Cranking Voltage Discovery

8 logs 39m logged 958 avg RPM 28 stalls

Day 6

Aug 14, 2026

PCV Fix, Idle Dialed In, First Road Tests

7 logs 96m logged 888 avg RPM 2 stalls

Day 7

Aug 16-17, 2026

Thermostat Replaced & Final Validation

2 logs 109m logged 859 avg RPM 10 stalls

Day 8

Aug 18, 2026

Updated Tune Validation (Cold Start)

1 log 23m logged 964 avg RPM 3 stalls

03Final Validation Run

Log 2026-08-17_19_46_04.mlg — 1,295 s, 19,432 records, cold start at 88 °F through full warmup, including rev events to 5,809 RPM. Full detail on the Day 7 page.

951 ±48

Idle, fan off (steady window)

917 ±82

Idle, fan on (steady window)

+51

RPM error (5.7%)

195.9°F

Peak coolant

Fan cycles

on 194 / off 190°F

5.58 V

Cranking voltage

unresolved

Final validation run trace — Actual vs target RPM with coolant temperature, final validation run (2026-08-17_19_46_04.mlg).

04Estimated Engine Performance

Vehicle Speed reads 0.00 kph in every log on file, so no dynamometer-grade output figure can be calculated — rusEFI's virtual dyno requires a working VSS input and a WOT pull, neither of which exist in the current log set. No wideband O₂ is installed either. The figures below are physics-based estimates from logged airflow, not measurements.

135–151

Estimated Peak Flywheel Power

at 5,800 RPM (naturally aspirated)

not derivable (no torque data)

Estimated Peak Torque

at 4,600 RPM

89.4%

Peak Volumetric Efficiency

assumption range, projected to 7,000 RPM

Performance Note The figures above are physics-based estimates from logged airflow, not measurements. Wideband O₂ feedback is required before adding timing or aggressive tuning.

05Engine Health & Telemetry Metrics Audit

Measured across raw datalog files to evaluate intake efficiency, starter battery health, electrical charging stability, and closed-loop idle performance.

Telemetry Channel	Baseline / Target Limit	Measured Value (Day 7)	Status / Health Assessment
Warm Idle Vacuum ($\text{MAP}_{\text{idle}}$)	30.0 – 36.0 kPa	33.2 kPa	EXCELLENT Solid manifold vacuum; no unmetered intake leaks.
Idle Stability ($\sigma_{\text{RPM}}$)	±50.0 RPM	±48.0 RPM	EXCELLENT Tight Open Loop control holding 951 RPM idle target — no PID feedback in use.
Alternator Load Droop ($\Delta V_{\text{batt}}$)	< 0.40 V under load	14.20 V → 13.90 V	PASS Charging system handles dual radiator fan engagement well.
Cranking Duration ($T_{\text{crank}}$)	>10.0V minimum	5.58V measured	MARGINAL Extended start duration caused by 5.58V battery voltage sag.
IAT Heat Soak ($\Delta\text{IAT}$)	< 15.0°F above ambient	+22.4°F at idle	MONITOR Normal for stationary garage testing; drops quickly once rolling.
Peak Volumetric Efficiency ($\text{VE}_{\text{max}}$)	> 85.0% NA	89.4%	CALCULATED Peak airflow observed during WOT road pull at 4,800 RPM.

05bCooling & Ring-Seating Evidence

Supporting charts for the root-cause and telemetry sections above.

Coolant peak by session — Peak coolant temperature per session. Thermostat replacement on Day 7 dropped the ceiling from 213–215°F to 195.9°F.

Pre vs post rev comparison — Same commanded idle position, less throttle opening — yet 7.6 kPa more vacuum and 214 more RPM after the engine's first hard revs. Evidence of piston ring seating in progress.

Warmup tracking error — Idle tracking error across the warmup range, final validation run.

06Actionable Next Steps (Hardware Checklist)

Priority	Item	Detail
HIGH	Cranking voltage collapse	Drops to 5.58V under load. Load-test battery, clean/torque grounds and starter feed.
HIGH	Wideband O₂ Integration	Gates all VE fuel auto-tuning and ignition mapping. Signal pin available at input D14.
DONE	Valve lash adjustment	Set to 0.007" intake / 0.008" exhaust, stone cold. Recheck after 3–5 heat cycles as the fresh valves seat.
MED	Ring seating	Underway, measurable already. Needs varied-load driving.
LOW	VSS input	Reads 0.00 kph. Required for virtual dyno and gear-dependent boost/idle tables.
LOW	Knock calibration	Flat −20dB placeholder. Profile noise floor before adding timing.