Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries are required to reduce vehicle emissions and to maintain them at a low level; and therefore to participate in a cleaner and healthier environment. The LS-Design™(Longitudinal Structure) metallic substrates with LS foils have been proved to be capable of improving conversion behavior, even with smaller catalyst size. Specially this developed foil structure, which transforms a laminar exhaust gas flow into a turbulent one, significantly improves exhaust gas mixing behaviour in the catalyst.In this special period of time where BS4 applications will start appearing in the Indian market in the near future, this publication will deal with the experimental results achieved with different metallic substrate foil structures on one leading “state of the art” BS3 four stroke motorcycle technology, developed for the Indian market. The impact of turbulent substrate LS-Design™ foil structures compared to standard and other TS-Design™ (Transversal Structure) structures tested under WMTC driving cycle on roller bench in fresh state are discussed in depth. Emissions results are showing that substrate with LS-Design™ perform better than the other and help to fulfil the proposed BS IV emission legislation.