1.7B model with Width-7 convolutions beat a 12B Qwen on long-horizon reasoning after one SFT run

Thrumpwart · reddit · 2026-10-31

A Reddit experimenter doing RYS layer duplication and geometry tuning on small models found that Liquid AI's LFM3 1.7B — expanded to 3B — beat their best Qwen 3.5 9B (12B after layer duplication, SFT + 8 RL runs + SLERP merges) after a single SFT run of 107 minutes (2,600 steps, 100k samples), versus 14–18 hours per Qwen SFT. The reason: LFM3's Width-7 Convolutions/SWA/GQA architecture, with 20 stacked Width-7 Gated ShortConv layers, aligns with long-horizon state-tracking reasoning, while Qwen's Gated Deltanet is suboptimal. Ironically Liquid AI explicitly advises against using LFM3 for complex multi-step reasoning, and two LLMs said it wouldn't work. Lesson: architecture-task fit can matter more than parameter count.

Original post →

More from Models

Models channel →