Mass Air Flow Sensor

I have a 1988 Iroc with a 350 tpi is there a limit on distance between the mass air flow sensor and the throttle body. I would like to add a cold air intake and put the m.a.f.s. inside the cold air intake box???? Also does the sensor need to be horizonial ? I ran 14.60 in the 1/4 last saturday with 91 dgr. ambient air temp. is that a good time for car.:confused: