Dayco Timing Belt - 17mm x 93TDayco was the first to develop the raw edge sidewall construction V belt, which facilitated controlled slippage around pulleys. About Top Cog V belts: Raw edge construction is combined with the Dayco patented cogged top design to ensure the top performance that todays vehicles and drivers demand. The Dayco Top Cog V belt delivers more flexibility and increases airflow around the belt, so it runs cooler and lasts longer than competitors' V belts. Three