hello, i just did a gasket match but by doing that it opened the ports up big time. i have felpro gaskets, not sure of the part # now but what a difference. i have not installed it yet. i slightly ported just the exhaust ports on the car before but not too much. i am debating if i should open up the ports where the upper and lower bolt together but i don't think i will. this is a stock engine besides dual exhaust. we will see what i get out of it when i have the injectors to put back in it. i did put a 91 5.0 HO tbird's fuel pump in last week since my old one gave out.