That's interesting information to know as far as the weight difference.
The guy I'm buying the EF Hatch from claims that the D15 motor in the car only has 40K miles on it but that there is a wiring problem and the car won't start. He does claim it will roll start. He says it's a D15B. Doing some research shows that if it is indeed a D15B that it's a JDM motor and has about the same HP as the D16Y8. However, I don't think the guy knows anything about Hondas and am not counting on that being the case. My guess is that it's probably D15B1.
Either way if it does in fact only have 40K miles on the motor is there any use in turbo charging a D15?