Got Shell 93 Octane and now barely idles 1973 Dart 340

AJ/FormS said

Solve the engine problem first
later the hissing booster connection.

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I was just wondering if the brake booster having a vacuum leak might be affecting the engine issue.

Not sure what else to do, other than a possible internal carb issue. It's an older Carter competition series AFB 9635SA from the early 90s