4" Intake Setup?

[darkfa8]

Aside from the ESP 4" MAF pipe.. does anyone know where I can find 4" or 3-5/8" ID flexible cold air ducting with smooth internal bore?

 

[Fuelie600]

Detroit flexable metal (hosenow.com). Item FLX2005 Flexfab silicone hose--smooth internal wall/ look it up for details. BUT you need to buy a minimum of 12ft.. (3 5/8" is an odd size). I purchased 12 ft. of 3.5"and have 10 ft left over. If you don't need 12 ft. and 3.5" will work, E-mail me and I will sell you some. Brian