The present invention relates to the technological field of cast iron alloys for automotive and similar applications. Problem to be solved: presently, structural parts of internal combustion engines are made of gray cast iron alloys that rarely have a tensile strength limit range greater than 350 MPa or vermicular cast iron alloys that do not remain stable at high temperatures. Solution of the problem: it is disclosed a vermicular cast iron alloy that, due to the addition of amounts of Molybdenum, Copper and Tin, with Hot Resistance Factor from 0.5 to 1.7% (HRF = 3 * (%Mo) + 1 * (%Sn) + 0.25 *(%Cu)) achieves a tensile strength limit of 500 to 550 MPa at room temperature and up to 300 DEG C, and a tensile strength limit of 430 to 450 MPa at 400 DEG C.