This ring pack comprises a tungsten coated stainless steel top ring with increased ring tension to reduce blowby at increased engine speed and combustion pressure. The ring pack is Cosworth specific and has been designed and validated for use in racing and road engines such as the Formula Atlantic and Caterham CSR260. Rings can only fit with Cosworth pistons. The pack includes a set of 4 top rings, 2nd rings and oil control rings.