Newbie Question about D16A1 motor...

This may be a dumbass question, but if it is, please forgive my dumbassness. I wanted to ask the people that'd probably know the answers best.

What is the difference between the motor in an 89 integra ls - D16A1 DOHC motor producing 118 hp - and the later integra JDM DOHC VTEC engines that crank out 160 hp?

What could I do to make a D16A1 motor produce power like the VTEC models do?
What else could I do to the engine to make it more potent (without a turbo or nitrous)?

Thanks alot and I appreciate your expertise.

there's a million differences between those two motors, and its not worth getting into....

The 89 integra motor is pretty much worthless for any application from 1988 and up. That motor belongs in the car it came in.

You can extract power out of a lawn mower if you wanted to...Its all about your preference, and budget. B series motors tend to be the easiest to tune and most universal. Parts can be used from several different motors to achieve your desired weapon of choice. Most choose to go vtec, but there are other options out there.

Again, it depends on your car, and your budget....do some research.