幾架既英文係咩?

Train是個可數名詞/countable noun，所以在寫的時候是沒有量詞的。

One train bound for Guangzhou was delayed this morning.
Two trains bound for Guangzhou were delayed this morning.

幾部火車用some沒有問題，你也可以用a few。
Some trains were delayed because of the signal failure.
A few trains were delayed because of the signal failure.

蒸氣火車是a stream-powered locomotive；在這個時候，你不會用train這個字，因為它指整列火車。蒸氣的只是跟火車頭有關，所以你會寫locomotive。

I think the 發問者 prefers Chinglish as well.

唔用some可以用few:
There are few trains.... (都係用呢d字)

亦可以用fleet,不過似形容一隊車隊:
A fleet of train.

fleet (VEHICLES) Hide phonetics
noun [C]
a number of buses, aircraft, etc. under the control of one person or organization:
He owns a fleet of taxis.