In this work, we propose extensions of our Phone-based Pronunciation Model (PPM) for analyzing dialect differences. We compared these systems using 3 metrics and 2 datasets of English. Empirical results suggest that (1) sophisticated tying is suitable in modeling deletion transformations across dialects, beating standard tying by 33% relative, and (2) APM (Acoustic-based Pronunciation Model) improves performance in generating dialect-specific pronunciations, dialect identification and rule retrieval, achieving relative gains beyond 34%.