Actually it won’t raise your stock rev limiter, you need another computer to do that.
The stock rev limiter cuts off the fuel at 6250 rpm's but you can raise it to 6450 by wiring the fuel pump to the ignition; at that point the computer cuts off the injectors. Having the fuel shut off is not the best way to control rpm's especially if you ever run NOS. The msd controls rpm's by cutting out spark.
The coil in the mustangs is a pretty good unit, so you probably will not notice much gain in performance but it is still a good piece to have.
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James Cox
nochevy@hotmail.com
1991 Mustang LX
12.565 @109.38mph 1.764 60ft