i know what it means, but really, I dont see how it makes THAT much of a difference. About what is the difference in HP from a single and dual overhead?

Also wonderin how the hell I can find out what my engine is?

all i know is its a SOHC vtec
wanna know:
1.5L? 1.6L?
Year?
Model?

a friend of mine let it go for hella cheap and even did the install, but didnt quite specify what it was.

my stock engine was like a D15 or D16? thats what I was hearing alot of, but got no clue what I had.

sorry, im a noob

Here it is, if that helps