What you're gonna lose if you get rid of the long runner intake is bottom end torque. You might pick up a bit of top end power - but for a street car, bottom end torque is what makes one fun to drive. Also, an air cleaner mounted on top a la carb style picks up the warmest air possible - from the underside of the hood. For every 10F increase in intake air temp, you lose 1% HP. So even if you went to a tbi set up, you'd want to 'snorkle' cold air to the intake.