Runflat tire with different modulus or elongation carcass cords

A tire having a tread, a belt structure and carcass radially inward of the tread and belt structure, the carcass comprising:

• at least one first ply reinforced with cords having a modulus E of X, the at least one first ply having a pair of ends wrapped around a pair of inextensible bead cores, the carcass having a pair of sidewall structures extending radially inwardly from the tread, each sidewall structure having at least one first runflat insert radially inward of the at least one first ply, a second ply structure extending to each bead core and spaced from the at least one first ply by a second runflat insert in the sidewall structure, the second ply structure being reinforced with substantially inextensible cords having a modulus greater than X.

A tire having a tread, a belt structure and a carcass radially inward of the tread and the belt structure, the carcass comprising:

• a pair of inextensible bead cores;
• at least one first ply reinforced with cords having a percent elongation of greater than Y, the at least one first ply having a pair of ends extending at least to the bead cores;
• a pair of sidewall structures extending radially inwardly from the tread, each sidewall structure having at least one runflat insert radially inward of the at least one first ply, a second runflat insert, and a second ply extending from radially inward of the belt structure to the bead core and being spaced apart from the at least one first ply by the second runflat insert, the second ply being reinforced with cords having a percent elongation Y, and wherein at least one of the plies has a turnup end wrapped around each bead core and extending radially outwardly.