Record-high critical temperatures ($T_{\mathrm{c}}$) of elemental superconductors have been rapidly updated under extreme pressures, yet typically only above the megabar regime. Preserving such high $T_{\mathrm{c}}$ at lower pressures remains a fundamental challenge. Here, we demonstrate that strategic alloying of Ti with controlled amounts of Al yields a family of Ti-Al intermetallics with ω-Ti-derived topological motifs that can be quenched to ambient pressure with substantially higher $T_{\mathrm{c}}\text{s}$. In particular, $\mathrm{T}{\mathrm{i}}_2\mathrm{Al}$ reaches an ambient-pressure $T_{\mathrm{c}}$ of 12.6 K, more than 30 times that of pure Ti. This enhancement originates from motif-preserving substitution: at low Al content, Al acts like hole doping, shifting the Fermi level toward a high density-of-states region, whereas at higher Al content, the weakened interlayer Ti-Ti metallic bonding drives significant softening of three in-plane Ti phonon modes, leading to enhanced electron-phonon coupling. This substitution strategy, which retains a key structural framework while tuning carrier concentration and lattice dynamics, may provide a transferable design paradigm not only for superconductors but also for other functional materials whose properties are governed by specific topological motifs.

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• Crystal structure
• Electron-phonon coupling
• Local density of states
• Nesting
• Superconductivity
• Intermetallic compounds
• Ab initio molecular dynamics
• Density functional calculations