I look on the wiki http://discoverygc.com/wiki/Ship_Equipment and I don't see anything. I bought an engine for 15 mil at Coronado the other day and it didn't do anything. The item description said "Varies". I really feel screwed. LOL
So, are there engines that make your ship go faster? Whenever I'm being chased it always seems like the other player catches up to me really quickly.
The engines are purely cosmetic changes. The cruise speed depends on the type of ship you're flying. Light Fighters will cruise fighter than, say, a Very Heavy Fighter or a Cruiser.
Sadly, for now different engines do not affect your ship's speed; they are cosmetic items, and have no variations in stats. The reasons that others may be going faster than you are either your ship class (for example, Light Fighters are faster than Very Heavy Fighters), or them using thrusters/cruise engines to catch up.
EDIT: Wow, double ninja. At least now you have a clear answer. Hope that helped.