84 falls flat -black smoke

[alec296]

my 84 falls on its face around 2300-2600 and around 6-7 psi (stock dashguages)boost then blows black smoke. eng and turbo stock only mod is 87 test pipe with kenn bell exhaust- ac rapid fire plugs.got car not running so have no idea how it ran before but prev owner put hotwire kit on so i think i might have to much fuel pres? no codes until today when it ran a code 42 so i changed plugs and tried split fires. it will run ok under light trottle and feels like it would move good if was hammerd . any sug? thanks andy

 

[WFO]

first thing-ditch the gimmick plugs and put in some ac cr43ts gapped @ .035".turbo regals are picky about their plugs...