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Just like the topic states, I was wondering if more power can be achieved using internals that are significantly lighter than stock? Less rotating mass means more power right?
 

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dailydriverz said:
I don't think you GAIN power, your loss due to inefficeincy is lower. you know what I mean? :D
Um I'm no expert by any means But logicaly speaking this is crap. Reason being is The engine is going to work just as hard regardless of what's inside it. That's what it's desgined to do. Saying it would reach a certian power and then quit just because it's easier dosne't make sense. It's designed to put out "X" amount of force to move the parts. It will still continue to produce "X" amount of force regardless of how easy or hard it is to get said parts in motion. And since the parts are now easier to move than OEM Logically it would be safe to say that Yes your going to get more power out of it.

Kind of like a train that supposed to pull 40 cars now take the same exact train and have it pull 20 cars at the same rate...... Your telling me that both set ups will arrive at exactly the same time??

Maybe we're saying the same thing maybe we're not But I would definatly think a engine with lighter parts (in the same set up obviously) would be more powerful.
 

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jakearooni said:
dailydriverz wrote:
I don't think you GAIN power, your loss due to inefficeincy is lower. you know what I mean?

Um I'm no expert by any means But logicaly speaking this is crap. Reason being is The engine is going to work just as hard regardless of what's inside it. That's what it's desgined to do. Saying it would reach a certian power and then quit just because it's easier dosne't make sense. It's designed to put out "X" amount of force to move the parts. It will still continue to produce "X" amount of force regardless of how easy or hard it is to get said parts in motion. And since the parts are now easier to move than OEM Logically it would be safe to say that Yes your going to get more power out of it.

Kind of like a train that supposed to pull 40 cars now take the same exact train and have it pull 20 cars at the same rate...... Your telling me that both set ups will arrive at exactly the same time??

Maybe we're saying the same thing maybe we're not But I would definatly think a engine with lighter parts (in the same set up obviously) would be more powerful.
no you do FREE UP LOST hp. which the end result or byproduct is in essence a gain in power.
yes you can make more hp due to the lighter parts.... but its not a gain in that form of the word 'gain'
all in all your helping make the engine more efficient. and thats what it all comes down to. how effiecient is the engine at producing work. how much power does it take to produce that work?

to make power you must use or burn power, right, right.

a conventional engine itself is a very ineficient POS..
the pistons get shoved down the bore pushing on the rods forcing the crank to turn. the piston accels down the bore at a rate only then to STOP (yeah talk about inefficient) and then have to accel again up to the top of the bore. only to stop again.... and repeat the process. all the time this motion is being forced onto the crank, but at the same time the rotational force of this is making HP its also robbing HP to help turn the rest of the piston/rod asm's and the crank and flywheel and so on so forth. turning the cam, the oil pump drive, pushing the lifters due to the cam, pushing open the valves ect ect..

the Lighter these pieces are: pistons/rods/crank/pushrods/valve springs/retainers/keepers/valves ect ect. all help in aiding power. by reducing the amount of HP lost from turning and moving them all.

think of it this way. someone makes you run for a kilometer with a 30 pound weight strapped to your back. takes you quite a bit of time.

now same person (you havnt gained strenth have you??) take the weight off, and run the same KM, how long does it take you?? alot less time. right?
now its not that you gained power or strenth have you? no. your able to run the distance with more ease due to the lack of excess weight. same thing for an engine.

its just like comparing a lightweight flywheel to a stock one. they dont make HP they free up hp. same theory for lightweight engine components.
 

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I like your explination colin. I guess my only other thought on it is even though it's easier the exact same amount of force is going to be used regardless of how heavy or light the components are right??? So if you dyno'd the new lighter set up compared to the heavier set up would you see a variation in numbers or no?

I mean I get what your saying. That the motor itself isn't any stronger But If I dynoed it and I get 135 hp and then I lighten it and now I'm seeing 145hp even though I just freed up some lost HP due to lightening the motor up and, according to the way I'm taking your explination the motor should have always been producing 145 hp but because it was bogged down it was only seeing 135 hp. Dosen't the end justify the means. Even if the motor was always producing the higher HP I never saw it until I lightened up the internals. therefore my new motor is more powerful than my old set up. Even though techinically it was always that strong. I never saw it.
 

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I like your explination colin. I guess my only other thought on it is even though it's easier the exact same amount of force is going to be used regardless of how heavy or light the components are right??? So if you dyno'd the new lighter set up compared to the heavier set up would you see a variation in numbers or no?
now which force are you talking about?
force against the crank? force turned out by the engine? force on the pistons? there are so many forces at work in an engine.
yes you would see a variation in numbers. with lighter stuff you'd see more power.

I mean I get what your saying. That the motor itself isn't any stronger But If I dynoed it and I get 135 hp and then I lighten it and now I'm seeing 145hp even though I just freed up some lost HP due to lightening the motor up and, according to the way I'm taking your explination the motor should have always been producing 145 hp but because it was bogged down it was only seeing 135 hp.
exactly. the potential for power has always been there. but due to the excess weight "robbing" hp it was not produced. now that its lighter its able to do its job alot easier, which in result increases the amount of HP produced.

Dosen't the end justify the means. Even if the motor was always producing the higher HP I never saw it until I lightened up the internals. therefore my new motor is more powerful than my old set up. Even though techinically it was always that strong. I never saw it.
yes the end result is a more powerfull engine. but thats due to better efficency and less rotating mass.
its exactly the same as comparing to a Crank HP #, to a true Wheel HP #. lets say 200 HP at the crank but due to having to turn the transmission the differential ect.. you only see 175HP at the wheels. its not that its making less hp. the full power is there and being produced. you just cant get it all due to inherent loss's of the drivetrain using some to produce the desired work to get the car to move.
 

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Colin is right on the money with his explanations. :D

To which I will add, the accepted efficiacy of fuel used to produce power is something as follows:

1/3 is used to make usable power at the flywheel.
1/3 is lost as heat through the cooling system
1/3 is lost as exhaust gasses
It will vary from engine to engine, but usually this is pretty close.

So the actuall used fuel to produce power is very little, lightening up the rotating and reciprocating masses in the engine means that for the same amount of fuel used the ratios will start to change a bit, usually lighter parts will cause less friction producing less heat, so you could end up with something like this:

40% used to make usuable HP at the flywheel.
28% lost as heat in the cooling system
32% lost as exhaust
These ratios are a bit exagerated but to illistrate the point I felt it was easier to do so. ;)

The problem with lightening parts is that usually some strength is lost and with the now freed up power stronger parts must be used so now more weight is added again, maybe in different areas, but it is a nessisary evil, and so a fine balance is nessisary to make a reliable engine. ;)

You can see why I like turbocharging so much, you can reuse some of that lost power from the exhaust, though you will never be able to regain all of it, since that would mean there would be no need for a tail pipe and unfortunatly would be a very different universe if that could happen. ;)
 

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long lost brother said:
Colin is right on the money with his explanations
why thank-you. :D

you pretty much summed up what i didnt go over.

as you can see by what the_raven posted. like i said even modern internal combustion engines are very inefficient. its sad to say but thats basically the ratios of how much fuel it wastes to make power. :(
 

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In all fairness, Jake, yes you were saying the same thing in the end. I just don't know where you got this:

jakerooni said:
Saying it would reach a certian power and then quit just because it's easier dosne't make sense.
or this:

jakerooni said:
Kind of like a train that supposed to pull 40 cars now take the same exact train and have it pull 20 cars at the same rate...... Your telling me that both set ups will arrive at exactly the same time??
who's telling you that? I didn't see anyone type that...Actually, I think everyone that answered this post including you, Jake, was right. Colin just stated it in the most legible way. :)
 

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It does not seem like it is practical to generate more power in this fashion with todays technology. Some engines have been made out of high carbon fibre plastic and ceramics, but they cost hundereds of thousands of dollars to produce. For our application, the cost of the light weight parts would be extreme. I think somewhere I read that a lightweight crank was available for a 3.1 but that is cost something like $1,200! Also light weight rods cost a fortune. Some parts may not be desirable to use if they are lighter, because as already stated, they may not be strong enough. Some parts may need to have a certain mass to be functional as the weight helps the part work more efficiently. (Ah, physics rears its ugly head.)Interesting stuff though.
 

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autodyne said:
um......first off making the engine lighter....does not effect HP as much as torque...
Suck what?

Horse power is a calulation of work over time, lighter parts will effect horse power way more than torque, seeing as the quicker you can accelerate an object the less horse power it takes while maintaining the same torque input.
Physics strikes again.
 
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