i just bought an ibanez rg370dx and set it up for standard tuning with the bridges faceplate parallel to the guitar. However whenever i use the whammybar the guitar goes out of tune? i streched the strings and everything. is this because the strings are new or did i do smthing wrong?
the strings will eventually come out of tune with the use of the whammy bar no matter how new the strings are or what kind they are. thats why they made the Wahwah pedal. it does the same effects as the whammy bar.
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1, edge III bridges go out of tune pretty quickly unless you take care of it well.

2, a wah pedal does not do the same thing as a whammy bar. its the tremolo pedal that does.

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Just because the bridge is parallel one way is just half of it. make sure the knife edges are exactly the same height, if they're not that will really mess things up.
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Check to see if the bolts that hold the locking nut to the neck do not protrude through the assembely, but are flush with the assembely so that when you tighten the locking nuts it clamps the strings and doesn't clamp on the bolts that hold the nut to the neck.
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