if you want a muffler, i would say imco, i had a imco race muffler(single chamber) on my small block 350 ans it sounded SWEET. i threw my flowmasters away. as far as a gl*** pack style, i would say porters
I had 3" flowmasters on my ford truck with 383 Chrysler, It was super loud. So i went with 3" dynomax ultra flow mufflers (like a flowmaster on the outside but a gl***pack on the inside) and Its super quiet now and you can feal it has more torque! It sounds great and I cant wait to put them on one of my other cars.