Which convertible car seats are best for babes that run hot?

Taylor

My son has always ran hot. Since he was born, he has been miserable in his car seat. The only way to keep him comfortable is if we blast the A/C. He sweats every time we put him in his Chico key fit.

He is outgrowing his infant car seat and we are in need of buying the next car seat up? Does anybody know what would be a good fit for smaller cars or what would make my baby less hot?