depends on the year of the escort... pre 1998 they had 1.9, 1.6, 1.3's
98 and newer it was either the 2.0 SPI or the 2.0 Zetec.
but to say there is not after market for the Escort that is total BS... ever hear of Cossworth???? weather it's an old escort or a new one they got LOTS of stuff will cost money but what good performance parts don't? There is a guy that lives by my parents that has a early 90's escort GT with a cossworth motor in it and it does 9's in the quarter

set him back about $10,000 for the motor shipped to the US. car not included.