It's completely safe, but won't do you much good without a tune to take advantage of the higher octane.
A lot of stangers get a CAI with a tuner. Do a site search on them, you will find plenty of threads.
AFM Site Administrator2006 Tungsten Grey Mustang GT Manual. Alpine H/U with Infinity speakers. Powerhouse CAI and Tune.
1978 2.8 L, 1979 5.0, 1982 5.0 "HO", 1986 5.0 GT
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