Intake I would make as large as possible since you only have atmospheric pressure feeding it. The rest being 1/4" should be ok since its probably relatively short.

If the hose was too small and you were pulling a large volume of air and/or have a long hose, you would have a pressure drop. For tires it would probably never matter since the valve stems are so restrictive, but IIRC you run air tools and stuff off yours.

'97 4Runner, '06 F350, '86 4Runner, '05 WR450
http://home.4x4wire.com/erik