Actually, with no internal mods, 15" of vacuum is borderline crappy. A new engine will pull 20"+, an engine w/100k miles on it will pull 17". My rule of thumb is 18" is expected. If it's more than that, fine. If it's less than that, I need an explaination, and look for it. With any internal modifications, my numbers are worthless.
Take care
~Chris
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Retired Moderator
MustangNet
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JimPorterRacing
RACECAR spelled backwards is RACECAR
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