boost question

[krisw]

ok now your just arguing the wrong things. obviously its physically impossible to achieve 100% efficiency, im not trying to find a supercharger that will do that. im just saying that assuming 100% efficiency they would flow the same amoutn of air.

[351wStang]

Originally Posted by krisw

ok now your just arguing the wrong things. obviously its physically impossible to achieve 100% efficiency, im not trying to find a supercharger that will do that. im just saying that assuming 100% efficiency they would flow the same amoutn of air.

Ok look dude, since you obviously refuse to listen and understand go buy a little blower and then a bigger blower. Put them on the same car and dyno the car each time. Obviously according to you nobody here knows a damn thing so go out and waist the money to prove to yourself that some people here where not born with their head up their ass.

This thread should be closed...

[SkylineUSA]

Originally Posted by krisw

ok now your just arguing the wrong things. obviously its physically impossible to achieve 100% efficiency, im not trying to find a supercharger that will do that. im just saying that assuming 100% efficiency they would flow the same amoutn of air.

No, that is not my point.

I see how you are trying to look at it, but its not the right way.

If two different blowers are 100% efficient, and both are blowing 10psi in the same intake, are they at the same RPM? Where in the rev range do they make 10psi, at the same point, with same volume, if that is the case they are the same blower, and not of different sizes that your mind is so wrapped up on. That is my point.

You want the laws of physics to agree with what you are saying, in that aspect you are making a mockery of physics?

[krisw]

Originally Posted by SkylineUSA

No, that is not my point.

I see how you are trying to look at it, but its not the right way.

If two different blowers are 100% efficient, and both are blowing 10psi in the same intake, are they at the same RPM? Where in the rev range do they make 10psi, at the same point, with same volume, if that is the case they are the same blower, and not of different sizes that your mind is so wrapped up on. That is my point.

You want the laws of physics to agree with what you are saying, in that aspect you are making a mockery of physics?

it just doesnt seem possible to me. explain to me how you can create the same pressure within 2 intakes and have more air in one than the other?

[MrSpace]

man, are you laughing at us or you really don't WANT to understand?

we've explained you 438732 times how it work and you seem to be so sure that we're all untrue that you even go ask on other forum until you find one where one person will say as you and then you think you are right?

Take another analogy. Make it a river 30ft wide. Somewhere in the river, it goes to 15ft wide. The depth is always the same.

Now, on that same river, you can have a good flow (for water, it's cubic feet of water per second) and that restriction of 15ft will create the backpressure.

Now, on the same iver, you could flow twice the amount of water (ft³/sec) and still get the same level (the water level won't increase, just the current will be stringer) and the same backpressure. The water will only flow way faster from the start to the end of the river, but the level will stay the same.

In a river there can be very strong current or almost no current and the level still the same, the backpressure created by the 15ft place will be the same.

Now for more mods, you can dig that 15ft to make it 25ft, you will then be able to flow even more water before getting at the max capacity of that river.

Come on, this thread should be closed, I'm sure we can show you srawings, everything, but still you will be sure that we are not right and you are. Then why ask the question if you don't want the real anwser?

I know a guy who took out his supercharger on his C230 kompressor, then he changed it for a Turbo. The SC was at 11psi and pushing 160whp, now the turbo is not even at 9psi and pushing 268whp. See, if both units were at 10psi, the turbo would flow way MORE air into the car but at the same backpressure.

If I continue, my next reply will need teletubbies for you to understand

Etienne

[SkylineUSA]

Originally Posted by krisw

it just doesnt seem possible to me. explain to me how you can create the same pressure within 2 intakes and have more air in one than the other?

I have written it over and over again, along with some other guys.

[duplox]

I don't think locking this thread is enough, just delete it. It should be erased from existance, anyone who ever mentions it again should be bludgeoned. Everytime I see 'Response to post "boost question" in my inbox I want to beat my head against my desk.

[SkylineUSA]

No, there is some good info in here for some of the newer guys

[351wStang]

Originally Posted by SkylineUSA

No, there is some good info in here for some of the newer guys

Ya this thread has really helped me understand more about boost and how it works. Thanks guys to those of you who made helpfull replys.

[GTStang]

I was thinking about closing it a while ago but I figured at some point the original questioner would understand.... maybe I was wrong but I'll leave it be for now.

[breaknstuf4fun]

hmmm...i htink he's just looking at pressure wrong (this is just how i view it, and it makes sense to me, but maybe this is what they've been saying all along).

Pressure is techinically, in a sense the same as density, except it's not one solid material, but a gass with in a solid container. so if you have a a container that's volume is 130 cm3, (say 1g = 1 cm3) and you put 260g of gas in there, because of gas's properties, it's giong to squish up and compress, which is pressure. now that is just in basic phsyics clas (please correct if i'm wrong here)

now..when talking about super charges, i tend to look at PSI as more of an indirect measurement of flow. the s/c has a 130 cm3 volume (for exapmle of course) the faster the fan spins the more mass will be introduced into that volume there for creating more pressure. now when a gas compresses it has a tendency to want to expand, which it can't really do, so it heads as quickly as it can (or at a velocity proportional to the need to expand from the compressed air) for the area with the less resitance, which would be the exhaust port of the s/c (as in the hole that connects to the manifold). Now, this also means (in concern with the volume) the larger the volume the more mass needed to create a certain amount of pressure. now i'm sorry if this seems it's all just being slapped together, which it is, so if one of the wiser ones wishes to fix this go ahead. SO, if you want you're larger s/c to achieve, say, 5 psi it needs more mass of gas, or volume that's the word the rest of you hvae used for it so after this i'll stick with that, in order to achieve that (dur), which means it will be pushing more air at 5 PSI than the smaller volume s/c would be pushin at 5 PSI.

ADD CORRECT AND REARRANGE AS YOU WISH, but stop with the uber techincal, and mathematical parts, make it sweet and blunt, like you're explainging it to a 13 year old, less confusin that way

[tturnpaw]

Originally Posted by 351wStang

Ya this thread has really helped me understand more about boost and how it works. Thanks guys to those of you who made helpfull replys.

If he doesnt understand now, he wont ever. Besides, i think hes out of excuses of why he doesnt understand now.

[JSSheridan]

Originally Posted by krisw

but the amount of air a supercharger flows and the pressure within the intake manifold are directly related to one another.

This is where I believe you are going wrong. The amount of air a supercharger flows and the pressure within the intake manifold are inversely related to one another. Notice in the charts posted earlier in this thread that the air flow at 5 psi is greater than the airflow at 10 psi. The pressure in the intake is going to resist the movement additional air into the intake from the s/c. To move air, you need a difference in pressure between two points, and the bigger difference results in more flow. The more powerful the s/c, the bigger pressure difference it creates. A large s/c will create more power than a small s/c at identical rpms. For instance, a large fan has more blade area and the tips of each arm are moving at a greater linear speed. Also, the pressure in the s/c will not be the same as the pressure at the intake because each volume has different characteristics.

Would everyone else agree with this?

By the way, MrSpace, if you want to add air to a container and keep the same pressure, are you sure you wouldn't want to lower the temperature and slow the molecules down?

[SkylineUSA]

Originally Posted by JSSheridan

This is where I believe you are going wrong. The amount of air a supercharger flows and the pressure within the intake manifold are inversely related to one another. Notice in the charts posted earlier in this thread that the air flow at 5 psi is greater than the airflow at 10 psi. The pressure in the intake is going to resist the movement additional air into the intake from the s/c. To move air, you need a difference in pressure between two points, and the bigger difference results in more flow. The more powerful the s/c, the bigger pressure difference it creates. A large s/c will create more power than a small s/c at identical rpms. For instance, a large fan has more blade area and the tips of each arm are moving at a greater linear speed. Also, the pressure in the s/c will not be the same as the pressure at the intake because each volume has different characteristics.

Would everyone else agree with this?

By the way, MrSpace, if you want to add air to a container and keep the same pressure, are you sure you wouldn't want to lower the temperature and slow the molecules down?

100% Right on man. Good way of looking at it.

[MrSpace]

that's why there is an ontercooler, to further pack more air into the same area and pressure.

PV = nRT where T = temperature.. simple equation.
if you keep pressure and volume constant and pack mre air, then you lower the temperature!

basic physics