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There are a few others here that you will probably want to hear from but I wanted to ask you about the symptoms.
When it shuts off, is it sudden or as if you turned the key off or does it sort of lose power gradually?
Does this happen mostly when getting on plane or hole shot? Or, can you be cruising part throttle and then go WOT and it dies?
Have you noticed any fuel leaks? Have you checked that the fuel tank is venting properly?
Anything else you may notice might help someone trying to help you.
You may want to have the fuel pressure checked.
Good luck.