I have to respectfully disagree. You can always slap a turbo or blower on a bigger cubed engine. More displacement just means you start higher up in the power-making range Its true though, with todays technology its pretty amazing what you can do with smaller displacement. Like Jarrett's 1100hp 370 for example...but you'd know all about that!

You may be confusing torque with horsepower here. Displacement has everything to do with torque. The formula for torque is T=Force*radius, radius being radius of the crank, which is half the stroke. Force is proportional to piston surface area, which is Pi*R^2. Increase either piston radius or crank radius and you produce more torque. Horsepower is a function of RPM and torque because it involves units of time. More RPMs you turn, the more torque is applied to the crank per given amount of time, and hence the more power the engine puts out. Big blocks aren't big in the horsepower department because many of them never exceeded 5000rpms, while they still made high torque all over the graph. Unless there are airflow restrictions, all variables being equal, a big-cubed engine will make more torque just because of the physics of it.

 

Wow, Thank you all for sharing the knowledge. Thank you Lil Sis for checking my math.

There are multiple ways to get more Air in/out (displacement) of an engine...bigger bore, longer stroke, Forced induction, and NOS (I might have forgot one). But these are the ways to effectively increase displacement. This is what I was getting at with the no replacement for displacement saying.

Am I crazy to think this?

 

I never said big cubic-inch motors are obsolete or don't have a purpose anymore!
Just pointing out that that saying had it's roots back before other means of add-ons became a common thing. Using that saying today is a bit out of place since there is replacement for displacement.


What? Where do you come up with this stuff?
There are two components in the following formula...

Torque = Moment-of-Inertia x Angular Acceleration

Moment-of-Inertia = Piston Surface area
Angular Acceleration = Stroke

How do you ignore one, and expect Torque not to be effected? You should read up on the physics behind hydraulics before thinking that torque is only a product of Stoke.




No, not crazy and you are right actually. It's just the way you explain it makes me cringe. Maybe I'm just overtly **** or what have you but bear with me for a moment.
An engine is just an overly complicated air-pump, as you basically alluded to. The more air you can move in/out of this pump the more work it will perform.
However, moving air in/out is not directly related to displacement. (contrary to what I highlighted in your previous post)
Increased displacement is a means of moving more air through the motor, and back in the early muscle days, making the engine bigger was the easiest way to accomplish moving more air through the motor. Hence why that term came about.
Today, as you pointed out there are OTHER ways of increasing air/flow through an engine besides displacement. And each method produces different results in how that air is moved in/out and the work produced differs.

When I read...
It makes me think that your trying to say that there is no other way to move more air in/out of an engine than bigger cubes. Which is not true, not today anyways. And there is a point of diminishing returns when it comes to displacement, a 800ci will be severely limited in what it can do when compared to an engine half it's size running at 15lbs of boost.

Anyways, I'll get off my soap box.

 

Spoolin, Your ability to multi quote is unparalleled! lol

I get what you are saying. No thunder removed from FI guys. One day when I win the lottery, I will try the FI world.