Forza 3 has a 2009 release date with 400 cars and 100 tracks.

[waron]

Dr.KennethNoisewater said:
400 cars - not that impressive. 100 tracks is nice though.

Accoring to Wiki:

GT1 - 178 Cars/11 Tracks
GT2 - 650 Cars/27 Tracks (Already beats Forza 3)
GT3 - 150 Cars (Its back down, but the cars contain much more detail. Not sure about tracks)
GT4 - 700 Cars
GT5P - 71 Cars
GT5 - I predict over 1,000 cars.

 

if you consider that in GT series they count every posible version of the same car as new one then it's not that many. GT4 had maybe 140-150 different cars in total(there was 50 Skylines, 25 Lancers and 20 Imprezas).
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