Are you adding a bigger throttle body, MAF? Do you already have headers and exhaust? By itself you probably won't see much of an improvement, but I had an Explorer on mine before I went with the Cobra, and with the 65 mm TB, 73 mm MAF, and headers with 2-1/2" exhaust I was beating stock GTs with my pig of a convertible.
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86 GT, GT40P heads, Crane 2031, 1.7 RR's, Cobra intake, 65mm TB, 73mm Vortech, 24# injectors, MAC GT40P headers, 2-1/2" BBK H-pipe (w/cats), Flowmasters, 3.55s, Groundpounder subs and lower control arms, 277 RWHP.
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