This part is here by popular demand. If you would buy one of these, the model 4000-SII detailed here is lighter, quieter, and draws less current than other competitive models (as date of posting). It could be under $30 delivered.

Attwood Marine - Turbo 4000 Series II Blower
    1747-4 = Standard model - ignition protected
    1749-4 = Sealed motor also provides water resistance
13.6-VDC 3.5-Amps (5-amp fuse)
230-CFM free flow
    (30-mph wind from 4" diameter discahrge)
125-CFM flow in system
    9,000-rpm, 1.0-inch-H2O back pressure
"System" = 3-feet duct, one 90-deg bend, one collector box, louvered vent discharge.
    Size:   OD=4-1/2" H=5-1/2" L=6"
    3-year manufacturer warranty
Manufacturer's web page - Technical Specifications - Installation Instructions

See application as a carburetor cooler in Carburetor article CB-208.

Attwood Marine - Turbo 3000 Blower
    1731-1 = Standard model - ignition protected
    1733-1 = Sealed motor also provides water resistance
13.6-VDC 3.1-Amps (4-amp fuse)
145-CFM free flow
    (33-mph wind from 3" diameter discahrge)
100-CFM flow in system
    10,000-rpm, 1.0-inch-H2O back pressure
"System" = 3-feet duct, one 90-deg bend, one collector box, louvered vent discharge.
    Size:   OD=3-1/2" H=3-5/8" L=5-1/32"
    3-year manufacturer warranty
Manufacturer's web page - Technical Specifications - Installation Instructions

See applications as a carburetor cooler in Carburetor articles CB-208A and several more articles to follow.