I thought you said you were getting rid of the C4! Either way, you need lower gears. The timing and fuel pressure changes not having an effect confirms this for me. You are not reaching your engines potential. 3.55's are just plain no good for a built engine/auto trans combo.
Take care
~Chris
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Retired Moderator
MustangNet
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JimPorterRacing
RACECAR spelled backwards is RACECAR
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