My car does the exact same thing. It started after I installed the long tubes, pro chamber crossover, and cat-back, and removed the smog pump. My engine was stock at the time. I have since changed EVERYTHING on the top end of the engine and it still does this. I was thinking it was the O2 sensor that I had that was falling apart, but I swapped those out for new ones and it still does this.
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Too much to list. Best ET on the car so far with stock 2.73 gears - 13.73@102mph
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