Design and Construction
The 391 has a fiberglass hull and deck built in sandwich construction, an approach that improves the indoor climate. She carries a lead fin keel with a bulb, while the rudder was modified as part of the model’s running changes.
Overall length is 39.27 feet, with an 11.61-foot beam. Her length-to-beam ratio of 3.38 describes a relatively narrow hull by modern, volume-driven standards. Displacement is 14,330 pounds, including 6,067 pounds of lead ballast, for a ballast ratio of 42%. Those figures mark her as a firmly ballasted yacht.
A substantial update arrived in 1990, bringing a new and improved deck, a modified rig, revised keel and rudder, and a further-developed interior. Buyers should therefore be aware that two generations of deck and fitout exist within the production run.
Rig, Performance, and Handling
The Finngulf 391 has a fractional sloop rig and is significantly overrigged, carrying more rig than 86% of comparable sailboats. Her sail-area-to-displacement ratio is 20.2 with the ISO 8666 reference sail, rising to 23.3 with a 135% genoa. A displacement-to-length ratio of 233 places her among moderate racers.
The theoretical hull speed is 7.4 knots. Her capsize screening value is 1.91, and the Motion Comfort Ratio is 25.5. Wetted surface is about 38 square meters, while the immersion rate is roughly 218 kilograms per centimeter. In practical terms, she sits deep and loads heavily per inch of sinkage.
Draft varies from about 1.95 to 2.05 meters depending on load, restricting her to major marinas.
Accommodations
The 391’s interior was developed further during the production run, notably after the 1990 deck and fitout revision. The sandwich construction of the hull and deck improves the cabin’s indoor climate, a tangible liveaboard consequence of the building method rather than a merely cosmetic detail.
Production Changes and Ownership
The principal documented evolution came in 1990, with a new and improved deck, modified rig, modified keel and rudder, and a continuously refined interior. Although the core Södergren hull concept continued throughout production, buyers should treat pre- and post-1990 boats as sufficiently distinct in their decks and systems to warrant separate survey expectations.
The Verdict
The Finngulf 391 is a low-production Södergren performance cruiser with a deeply ballasted lead bulb fin, an unusually powerful fractional rig, and a sandwich-built hull that the record credits with providing a better cabin climate. Her narrow beam and heavy immersion rate will suit sailors who value stiffness and a moderate-racer pedigree over the convenience of marina hopping. The 1990 revisions also make it important to establish which generation an individual boat represents.
Pros
- Significantly overrigged fractional sloop, with an SA/D ratio of up to 23.3 under genoa
- Lead bulb fin keel and a 42% ballast ratio on a solid 14,330-pound displacement
- Sandwich hull and deck noted for improving the indoor climate
- Interior and deck developed through the 1990 revision
Cons
- Draft of 1.95–2.05 meters limits her to major marinas
- Fewer than 100 built, so spares and comparable boats are scarce
- Heavy immersion rate of 218 kilograms per centimeter penalizes loaded cruising
