'90 LX's, in my opinion, are the absolute BEST stang ever
. Go w/ the gears first, definately. Remove your air silencer, put in underdrive pulleys, and get a new shift kit (Pro 5.0 or Steeda Tri-ax). BFG Comp T/A's have treated me really well. Then, you'll be coughing up a little more cash (heads/intake/headers etc etc)
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'90 LX 5.0; 12K original miles (no sh*&); 3.55 gears; pulleys;Edelbrock Performer Heads; BBK shorties; MSD 6AL box w/ blaster 2 coil; Motorsport E303 cam; Pro-M 75mm MAF; BBK 70mm TB; Eibach spring kit; Southside welded subs; K&N cone filter charger; Hurst shifter; fiberglass turbo hood; A/C-less; rear seat-less; cat-less; 2 chamber Flos; Corbeau racing seats (fronts);
30# injectors; JMS Chip; 190 lb fp; TFS track heat Intake (12.299 @ 113)