[tireburner163]

Mid 13's are definaly possable with a good driver.

The Mass-air meter measures the amount of air coming into the motor and allow the computer to add the right about of fuel. It is stock on all 89 up 5.0's(88 if it was a cali. car). You probably have a bigger mass-air meter.

Well first of all there is only one cam. A aftermarket cam will more than likley sound "lumpy". The only real way to tell would be to measure the lift and duration. I not sure how(with the engien put together) to do that. PKRWUD or someone else will prob. know.

I'd say get a intake and bigger throttle body next.