i did plugs and wires and the car runs fine i went from accelle wires and acdelco 41-906 to msd 8.5 and ngk t55r and it runs and idles fine but when i go wot it stumbbles. all wiring is good i tripple checked it and all conections are good. i might take the plugs out and put in the old ones to see if it helps.

 

ttt

 

ttt i need some help. it also back fires at high rpms at wot. please help me.

 

(most likely) opti or coil, man