It was an official name. The V is for V-Line (a series of V-8 engines) CO is for Cab over. I'm not sure about the F, it might be for the axle setup. It has been suggested before on our website that VCOF might be for single rear axle setup and VCO is for tandem rear axles but it might be incorrect according to these sources:

http://forums.aths.org/Topic54532.aspx
http://www.binderplanet.com/forums/archive/index.php?t-57890.html

http://i.ebayimg.com/00/s/ODA4WDYyMA==/z/3jUAAOxyFPNSIyfJ/$(KGrHqF,!qsFIdhkrtK0BSIyfI0f)g~~60_12.JPG
http://www.hankstruckpictures.com/pix/trucks/ih/brochures/co190s/vcof_190a.jpg

http://books.google.co.jp/books?id=tZkEZc169PAC&pg=PA87&lpg=PA87&dq=vcof-190+vcof-200&source=bl&ots=cwZIgTCqLP&sig=6IfTmQ1lGtH5o3CN7VMPxCe-0aQ&hl=en&sa=X&ei=2esZU-erG-bnywO_vIDoBQ&redir_esc=y#v=onepage&q&f=true

Thus, some trucks on the website might be mislabeled.

engineact.com and similar other domains are automated web crawlers. They should be avoided.