Your exhaust is filled with fiberglass to deaden the sound. What you see blowing out is the excess. It will stop shortly. It will also change tone some too. Should get a little deeper.
93 with a Greddy turbo, I used a stock SRT-4 exhaust and cut it up and stuffed it in. I only used one outlet. This isn't the best example of it because the cameras mic is overloaded. In real life it really growls under load and has a deeper tone. In any case, here it is. Basically 2 cats and no muffler.
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