benzete said:
now, can you explain in detail/technical (while maintaing as much newbie words as possible) how each of those benefit?
Well, a bigger bore will just make your motor bigger. And generally speaking, a larger version of the same motor will usually end up making more power. An oversimplified way to think of boring a motor is this:
Let's say we start with our 2.0L motor, and you bored it out and and made it a 2.1L. Your motor is now 5% larger. You could probably expect somewhere near a 5% increase of power due to the size.
Basically, with a bigger bore, your motor is doing the exact same thing, but just on a slightly larger scale. It's a bigger version of the same engine. Boring a motor doesn't really change the power curve, it generally will just add power to the entire curve.
My guess is boring allows more fuel/combustion/etc and increase in volume/displacement thus more hp.
You got it.
I'm also going to assume that the shorter the stroke the more fuel gets dumped/ignited also allow more hp. Just a guess though based on the definitions. Don't hate.
You're off on that one. At a given RPM, a shorter stroke will allow LESS air into a motor. Make no mistake: if you increased the stroke on an FS-DE
from a 92 to say...100, and you revved your motor to 4000rpm, the 100mm stroke motor will make more power than the 92mm. At any given RPM that are within safe operation ranges of BOTH of the motors, the 100mm motor will make more power.
HOWEVER, the problem is that the 100mm motor is so extremely undersquare that it can't safely rev as high as the 92mm motor could (for various reasons). You'd lose hundreds of RPM off of your redline from the 8mm difference in stroke. See, when you change stroke instead of bore, you're changing the physics of the motor more, which may have negative effects, depending on what you're trying to accomplish.
Cliff notes:
GENERALLY SPEAKING*:
adding bore = more power everywhere.
adding stroke = lower redline, but more power than non-stroked until the new redline is reached.
*This isn't true in all cases, but most.