Setup Lab · Mercedes-AMG W13

Silverstone (Arena Grand Prix)

Combo started
2026-06-30
PB
88.457 (2026-07-05, session 44105a55d7678620 L41)
Theoretical
88.214 (all-time valid splits; the whole gap is S2: PB +0.184 there, ≤0.013 everywhere else)

Current keeper

measured, on record

Proved by session 44105a55d7678620 (2026-07-05 03:27), best 88.457. Conditions: track 18.3 °C, Softs, Attack deploy, 8 kg fuel.

Aero
DF trim High · front flap 0.00° · RW Gurney 0 mm · (calc: aero bal 48.06%, L/D 4.555, RH@speed 17.0/29.0)
Front
heave 850 N/mm · roll 370 N/mm · RH 25.9 mm (on the ~25 mm minimum)
Rear
heave 240 N/mm · roll 220 N/mm · RH 60.2 mm (on the ~60 mm minimum)
Alignment
camber −3.15° F / −1.68° R · toe −0.03° F (out) / +0.07° R (in)
Diff
preload 0 Nm · entry 3 · mid 5 · high-speed 6
Brakes
base 52.0% + BMIG 2 → total 53.0% · ramping 50% pedal
PU
EB 6 · deploy Attack (hotlap habit — Qual mode untested at current pace)
Tires
Softs · cold 165.5 kPa F / 144.8 kPa R
Fuel
8 kg (hotlap trim)

Settled knowledge

each finding points at the test that proved it
  1. Diff preload 0 beats 10 — clean same-night A/B, +0.24 s. T-007
  2. Front flap 0.00 is fastest of the 0/0.5/1.0/1.25 sweep; the slow-corner deficit is mechanical, not front-wing (T-004/T-006; Katz pp. 150–151 — wing load ∝ V², weak at 80–120 km/h).
  3. Total bias 53% beats 55%. T-003
  4. Gurney 0 + RH@speed 17/29 (from 10 mm + 18/34) transformed the car: vmax 288→310 km/h era shift. T-001
  5. Garage ride-height minimums ≈25 mm F / ≈60 mm R — we sit on both; rake is regulation-fixed, heave is the only remaining platform lever.
  6. Cold 165.5/144.8 kPa produce centered tread temps (middles within ~2 °C of edge averages) — pressures are dialed at 18 °C track.
  7. LF is the limiting tire (hottest face 117/121/130 OMI; fastest wear — mid tread 73% after the long 07-05 set). Softs won't live a race stint here.
  8. 15 kg fuel cools all four tires ~15 °C at identical settings → race trim will drift understeery (T-008 constants comparison).
  9. Front heave is a live S2-vs-floor-margin trade: 750 owns S2-best (Loop 90 vs 83 km/h) at 0.5 mm plank minimum; 850 keeps 4.5 mm and the overall PB. T-009
  10. Zero bottoming events recorded on any analyzed lap — no porpoising trade currently active.

Every test on record

10 tests · newest first
T-010

Front heave 800 (the split)

queued QUEUED
Hypothesis
800 keeps most of 750's S2 gain with real plank margin; full package spec in data/stint_lab/w13-silverstone-proposal-2026-07-05.md.
Gate
plank min ≥2 mm on telemetry, no bottoming → else close at 850.
Protocol
2 flyers in Attack (comparability), read S2/S3 + plank; if good, one run in Qual deploy for the real number (Qual untested at current pace).
Driver read

Awaiting the driver's read.

T-009

Front heave 850→750

closed 2026-07-05 04:40
Hypothesis
softer front heave = slow-corner front compliance = S2 (Milliken Ch 22.6 platform regime; the S2 gap is mechanical per T-004/T-006).
Baseline
PB config, 88.457.
Change
F heave 850→750 (F RH read-back 25.9→25.3).
Measured
88.580 (b1fd2c25795bc99b L76) — all-time S2-best 17.352 (Loop 90 km/h vs PB 83) and S5-best 16.816, but S3 27.664 (vs 27.455 best) and front plank min 0.5 mm (PB lap: 4.5 mm). Zero bottoming flags on both.
Garage action
session ended the night; unresolved.
Driver read

Awaiting the driver's read.

Next: T-010.

T-008

Repeatability + 15 kg fuel run

closed 2026-07-05 04:00–04:07
Baseline
PB config.
Change
none, then fuel 8→15 kg.
Measured
88.940 confirm (24a78af4); 88.724 at 10.9 kg on-lap (bbb11f18) — pace holds within ~0.3 of PB at +7 kg; all four tires ~15 °C colder on the garage sheet at the heavier load.
Driver read

Awaiting the driver's read.

Next: race-trim implications queued (Mediums, flap compensation).

T-007

Diff preload 10 vs 0

kept in garage 2026-07-05 03:09–03:27
Hypothesis
community's one strong W13-specific direction is preload LOW for entry rotation (W13 research §2.5; SF23 doc found the same for its car).
Baseline
4df3284c3c00341f 88.694 with preload 10 (F heave 850, F RH 26.2, R heave 240).
Change
preload 10→0 (flap/F RH restored to 0/25.9 in between, 89.105 intermediate at f81ba694).
Measured
88.457 PB (44105a55d7678620 L41). Cleanest A/B of the week.
Garage action
preload 0 kept.
Driver read

Awaiting the driver's read.

Next: fuel-load check (T-008), front heave sweep (T-009).

T-006

Front static RH to minimum + entry diff 4→3; flap 0.5 probe

kept in garage 2026-07-05 02:53–03:20
Hypothesis
front on the deck + less entry lock = slow-corner rotation (W13 doc §2.2, §2.5; community: rake/rotation first, wing last).
Baseline
89.038 (T-005).
Change
F RH 27.6→25.2 (minimum), entry diff 4→3, R heave 260→250; then flap +0.5° with F heave 800 (0f6992a3, one lap); then flap back to 0.
Measured
89.133/89.153 back-to-back (4757718a, spread 0.02 — very repeatable); flap 0.5 probe 89.427; owns all-time S4-best 16.690.
Garage action
F RH minimum + entry 3 kept permanently; flap returned to 0.
Driver read

Awaiting the driver's read.

Next: diff preload (T-007).

T-005

Rear heave 260 + rear roll 220 (+ front camber −3.25→−3.13, toe trims)

kept in garage 2026-07-05 02:08
Hypothesis
stiffer rear platform steadies the high-speed rear (Stowe/Becketts).
Baseline
T-004, 89.590.
Change (small package)
R heave 220→260, R roll 185→220, F camber −3.25→−3.13, F toe −0.05→−0.03, R toe +0.05→+0.07.
Measured
89.038 (0c59ba0935ea7083); owns all-time S3-best 27.455 and the highest Stowe minimums (239–240 km/h) — but S2 17.53–17.77.
Garage action
R roll 220 + the alignment kept; R heave later walked 260→250→240 (T-006/T-007 sessions).
Driver read

Awaiting the driver's read.

Next: front-end grip for S2.

T-004

Baseline restore (flap 0, bias 53% total, R roll 185)

baseline 2026-07-05 01:53
Measured
89.590 (23f84c9b542e6839) — reference for the night.
Garage action
night proceeded from here.
Driver read

Awaiting the driver's read.

T-003

Bias 53+BMIG3 (total 55%) vs 52+BMIG2 (total 53%)

reverted 2026-07-02
Hypothesis
more front bias protects entry stability (research default direction is forward; fast-driver direction is rearward — W13 doc §2.6).
Baseline
total 53.0% running 88.95–89.22.
Change
base 52→53, BMIG 2→3 (total 55.0%).
Measured
best 89.461 (ba5113eb, flap-confounded); reverting to 53% on 07-05 restored 89.0s immediately.
Garage action
reverted 07-05 01:53; 53% total kept since.
Driver read

Awaiting the driver's read.

Next: leave bias family; EB never touched (queued).

T-002

Stiffer platform probe (F heave 950, R heave 250, R RH 60.9)

reverted 2026-07-02
Hypothesis
more platform stiffness holds the floor better at speed.
Baseline
c85c7dbd3f0e8152 — 88.950.
Change (package)
F heave 850→950, R heave 220→250, R RH 60.2→60.9.
Measured
89.203 single lap (fcdff14b1eed1d8e); follow-up variants with flap 1.25/1.0 + F heave 900→850 ran 89.50/89.46 (9874ad7f, ba5113eb).
Garage action
fully reverted by 07-05 01:53 baseline.
Driver read

Awaiting the driver's read.

Next: re-baseline, go one variable at a time (07-05 night).

T-001

Initial trim: strip the high-drag config

kept in garage 2026-06-30
Hypothesis
default-ish high-load config (flap 4°, Gurney 10 mm, RH@speed 18/34, F heave 1000) is overwinged and overstiff for Silverstone; research meta says floor > wings, run low (setup-work W13 doc §2.1–2.3).
Baseline
4fb8b28b4d19a419 — 94.157, vmax 283.
Change (package — exploration phase)
flap 4→0, Gurney 10→0, RH@speed 18/34→17/29, F heave 1000→850, F roll 240→420, R heave 250→220, R roll 130→180, BMIG 3→2, fuel 47→18 kg.
Constants
Softs, track 18.3 °C.
Measured
92.074 same night (0036f6e1a9da1642), then 91.006 (51d9b09e349a9e79); vmax 288→304. Pace kept falling all week on this base (driving + trim compounding).
Garage action
kept — this became the base for everything after.
Driver read

Awaiting the driver's read.

Next: fine trims (T-002+).

Up next

single variables, in order
  1. T-010 front heave 800 package + Qual-deploy flyer (above).
  2. Mid diff 5→4 — S2 rotation in Village/Loop; record the garage tooltip (source sign conflict, W13 doc appendix).
  3. EB sweep 6→4 and 6→8 — never touched all week; 2025 S4 made it part of the braking family.
  4. Front cold −3 kPa stint test vs LF mid-wear (82/73/74 after the long set — mid-fastest wear with centered temps is the open tire question).
  5. Race trim: Mediums baseline + flap +0.25–0.5° at race fuel (T-008 showed the ~15 °C cooling).