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Performance & Speed

Seguin 48 Performance

How the Seguin 48 performs on the water — racing handicap, speed, sail-carrying power, stability and comfort.

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The Seguin 48 is well-powered with enough sail area to move in light air, with a steady, comfortable ride offshore.

Hull Speed

The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.

8.2 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 37.5′, the Seguin 48 tops out around 8.2 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √37.5′ LWL = 8.2 kts

Performance Ratios

Racing handicap, sail-carrying power, stability and comfort — and what each one actually tells you about a day on the water.

SA / Displacement
21.3
Powerful cruiser/racer — quick in light air, reef early when it pipes up.
Ballast / Displacement
39.9%
Stiff enough to carry a big genoa comfortably into moderate breeze.
Displacement / Length
223
Moderate — a good balance of speed and load-carrying ability.
Comfort Ratio
30.3
Good offshore comfort — steady enough for multi-day passages.
Capsize Screening
1.85
Below the 2.0 offshore threshold — acceptable for ocean passages.
Hull Speed
8.2kts
S# (Speed Number)
2.9
Pounds/Inch Immersion
1lbs
Weight needed to sink the hull one inch — loading sensitivity.

Motion & Offshore Suitability

Two ratios that matter most when you're planning passages — how the boat feels in a seaway, and whether the hull geometry is suitable for open ocean.

Comfort Ratio
30.3
Good offshore comfort — steady enough for multi-day passages.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
1.85
Below the 2.0 offshore threshold — acceptable for ocean passages.
Under 2.0 — Acceptable for offshore
Over 2.0 — Coastal / protected waters

PHRF Fleet Position

Where the Seguin 48 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Racer 0–90
Cruiser/Racer 90–150
Cruiser 150–210
Monhegan 48 78s/nm
Alden 48 86s/nm
Cherubini 48 108s/nm
Hallberg Rassy 49 120s/nm
Hinckley 49 150s/nm

Estimated Speed by Wind

Rough boat speed estimates at different true wind speeds and points of sail — derived from hull speed, SA/D, and displacement, not measured polars.

Point of Sail 6 kts TWS 10 kts TWS 15 kts TWS 20 kts TWS
Close-hauled40–50° 3.7 4.6 5.2 5.4
Close Reach60° 4.4 5.6 6.3 6.5
Beam Reach90° 5.4 6.9 7.7 8.0
Broad Reach120–135° 5.0 6.4 7.1 7.4
Run150–180° 4.0 5.1 5.7 5.9
These are simplified estimates based on hull speed (8.2 kts), SA/D (21.3), and empirical efficiency curves — not instrument-measured polars. Real-world speed varies with sea state, bottom condition, sail trim, and current. Speeds in gold approach hull speed; bold gold means near or at hull speed.

Wind Range & Comfort Envelope

Estimated wind ranges for comfortable sailing on the Seguin 48 — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–6 kts 6–18 kts 18–26 kts 26+ kts
Ghosting
0–6 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
6–18 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
18–26 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
26+ kts
Storm conditions. Storm jib or bare poles. Seek shelter if coastal.

How It Compares

Side-by-side with the boats most often cross-shopped against the Seguin 48.

Seguin 48 Alden 48 Cherubini 48 Hallberg Rassy 49 Hinckley 49 Monhegan 48
Dimensions
LOA 48.7 48.8 48.8 49.1 49.0 48.6
LWL 37.5 37.1 44.0 41.0 40.4 37.5
Beam 13.8 13.5 13.0 14.5 13.4 13.8
Displacement 26 32 40 39 38 28
Ballast 10 13 16 17 8 12
Sail Area 1 1 1,249 922
Performance
PHRF 86 108 120 150 78
SA/Disp 21.3 16.7 17.3 13.1
Bal/Disp 39.9 40.6 42.3 45.1 21.1 42.7
Comfort 30.3 38.1 44.7 40.1 43.0
Capsize 1.85 1.70 1.52 1.70 1.60
Hull Speed 8.2 8.2 8.9 8.6 8.5