According to Wilford, the train is 10 miles long[2] (“Three thousand souls stufffed into a ten miles steel tube”). This would put the average length of a carriage at 15.56m (10 miles = 16.09km, 16.09km = 16.090m, 16.090m/1034 carriages = 15.56m per carriage).
how does that compare with snowpiercer?
Not as long
https://snowpiercer.fandom.com/wiki/Category:Snowpiercer_(Series_Train)_Cars#Snowpiercer_(Series_Train):_1001_Cars_Long