414 WHP Esmeril Racing Turbo RX-8
Answer my question first and I will answer yours. It was a legitimate question.
I will give you a bloody obvious hint, though (as if I haven't flat-out answered this before):
What causes pressure?
What causes pressure?
rersistance to flow causes pressure - I get that . You threw me by useing the term pressure ratio .
I don't get what you think is so wrong in my previous post though.
If you had a big reservoir of compressed air at a set pressure & temp. hooked up to a renesis inlet manifold and opened the taps the renesis would flow a certain amount of air and make a certain amount of horsepower . Does it matter how big the compressor was that made that air ? NO it does not . So long as temp and pressure are constant the mass air flow (therefore power) will be the same .
It seems to me from this and our last discussion in another thread that you don't get that pressure is a form of stored energy .
I don't get what you think is so wrong in my previous post though.
If you had a big reservoir of compressed air at a set pressure & temp. hooked up to a renesis inlet manifold and opened the taps the renesis would flow a certain amount of air and make a certain amount of horsepower . Does it matter how big the compressor was that made that air ? NO it does not . So long as temp and pressure are constant the mass air flow (therefore power) will be the same .
It seems to me from this and our last discussion in another thread that you don't get that pressure is a form of stored energy .
Last edited by Brettus; Sep 21, 2009 at 02:25 AM.
You Dumbass!!!
Joined: Feb 2008
Posts: 719
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From: New York
I thought the purpose of a turbo was to Force more air molecules there, by increasing the density of the air, thus more air molecules would be allowed into the intake... hence the term "forced induction".
lol you guys all crack me up...see like I said I didn't go to school for all this stuff or do the research...but you guys have managed to basically agree with me all though you all disagree. lol When I say 14 psi is 14 psi that's true....only thing that alters the power part here is your charge temps. I don't explain my thoughts or anything and I think you guys don't tend to follow me. Like I said my turbo maintains the 14 psi all the way up......it does die off at 8500...which is when I over spin the turbo. But like all of you have been talking..it's cfm's or its flow or its psi...all in all
if at 8500 rpm my turbo still holds 14 psi...that means my turbo is big enough and efficient enough to maintain it. That means there is enough flow of air (CFM's) to create pressure...14psi of pressure...there for they are equal in a sense.
The real power at this point is not going to be about rather each car is flowing more air or what size turbo but...engine temps, charge temps, and timing.
The big problem I had with my mazsport type 3 was heat. I have heat shield after heat shield on my intake...making sure that my intake air is the same as it is coming outta my intercooler.
Maybe today I'll get my brothers little 1/4 mile and power calculator thing that you put on the windshield and see what it shows for power. If it shows where I think I am...that's fine..but if it's more then I'll go get on a dyno... I don't have a fear of posting video with results.
if at 8500 rpm my turbo still holds 14 psi...that means my turbo is big enough and efficient enough to maintain it. That means there is enough flow of air (CFM's) to create pressure...14psi of pressure...there for they are equal in a sense.
The real power at this point is not going to be about rather each car is flowing more air or what size turbo but...engine temps, charge temps, and timing.
The big problem I had with my mazsport type 3 was heat. I have heat shield after heat shield on my intake...making sure that my intake air is the same as it is coming outta my intercooler.
Maybe today I'll get my brothers little 1/4 mile and power calculator thing that you put on the windshield and see what it shows for power. If it shows where I think I am...that's fine..but if it's more then I'll go get on a dyno... I don't have a fear of posting video with results.
#50
Joined: Nov 2007
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From: Caput Mundi
That's not it. What you fail to understand is that 14psi, hence boost, doesn't mean a whole thing in making power. Agreed that higher boost means higher flow (up to a certain limit where you blow everything) with a given turbochargers. The point is that 2 different turbines will FLOW a different amount of air at the same psi.
That's why we all use airflow (well, its mass) and not boost figures to understand what power outputs we can expect. That's the point, boost is not flow and flow is what makes power.
What happens if a turbo moves 60lbs\min of air at let's say 9psi and another one moves 45lbs\min @ 12psi... Then what turbo is producing more power?
That's why we all use airflow (well, its mass) and not boost figures to understand what power outputs we can expect. That's the point, boost is not flow and flow is what makes power.
What happens if a turbo moves 60lbs\min of air at let's say 9psi and another one moves 45lbs\min @ 12psi... Then what turbo is producing more power?
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From: Atlanta area
Boost is boost. 14psi is 14psi. Difference is, the harder a turbo has to work to maintain that 14psi is the determining factor on how much power is produced at a given rpm at that psi. Brettus and Mazdamaniac are essentially saying the same thing just a different way. same boost does not = same hp with 2 different turbos.
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From: Atlanta area
Driving habits are a big portion of how long something will last.
You Dumbass!!!
Joined: Feb 2008
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From: New York
I think hes just trying to make us think, hoping it will help us learn. If he tells us, we forget, if we learn, we remember... hopefully
Last edited by Symbioticgenius; Sep 21, 2009 at 02:09 PM.
3-wheeler
Joined: Dec 2005
Posts: 2,734
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From: Phoenix
Trying to make the case that pressure = power is completly false. As Giorgio pointed out, you could have two different sized turbos moving a set amount of air at the same pressure but one turbo will generate more power than another one. Flow generates power not pressure since pressure is resistance to that flow.
The primary issue is I'm seeing people getting their terms mixed up and substituting ideas in incorrect areas. You can't understand HOW this stuff works until you can speak the language.
That's not it. What you fail to understand is that 14psi, hence boost, doesn't mean a whole thing in making power. Agreed that higher boost means higher flow (up to a certain limit where you blow everything) with a given turbochargers. The point is that 2 different turbines will FLOW a different amount of air at the same psi.
That's why we all use airflow (well, its mass) and not boost figures to understand what power outputs we can expect. That's the point, boost is not flow and flow is what makes power.
What happens if a turbo moves 60lbs\min of air at let's say 9psi and another one moves 45lbs\min @ 12psi... Then what turbo is producing more power?
That's why we all use airflow (well, its mass) and not boost figures to understand what power outputs we can expect. That's the point, boost is not flow and flow is what makes power.
What happens if a turbo moves 60lbs\min of air at let's say 9psi and another one moves 45lbs\min @ 12psi... Then what turbo is producing more power?
You guys look at the lbs\min and that's not what you look at... you look at that when your sizing your turbo for your car...that's it!!
Look if you have a water hose.....1/2 outlet.....and you have a huge pump capable of flowing say the 60lbs per min...and the other will only flow 45...now think about this
If there is 9psi that means your trying to flow or push for water out that hose then it can handle...because of how much your trying to flow it creates pressure!!!!
So the 12psi would flow more cause it has more pressure. behind it making it flow that much faster
And that only happens as flow increases to a point where the smaller turbo becomes inefficient.
Originally Posted by Kane's Tuning Class
Gas Laws, WTF?
• General Gas Law – In any gas (liquid is a gas or gas is a liquid and they are both fluids; you pick), the combination of volume, pressure and temperature are related. A change in any one will affect a corresponding change in the others.
• Pressure and Volume are inversely related (Volume up, Pressure down),
• Volume and Temperature are inversely related (Volume Up, Temperature Down)
• Pressure and Temperature are proportional (Pressure Up, Temperature Up).
Cont.
• Pressure Gradient - Picture that old Jr. High Science Class Exp. No, not the girl who first let you touch her boob, focus! The one where you have two cups of liquid and a hose between them, lift one cup and the liquid will flow into the other (lower) cup. This is a good demonstration of a pressure gradient. Simply put, air is going to flow from the higher pressure, into the lower pressure.
• So in your engine cycle, the intake pressure is higher which moves the air into the cylinder. After combustion the expanded exhaust gas pressure is higher than the pressure in the exhaust so the air moves into the exhaust.
• The higher the "high" pressure / the lower the "low" pressure are, affects the velocity of that air movement. In boosted applications, this air is moving faster due to an increased pressure gradient.
Some More…
• Partial Pressure of Oxygen (PPO2) - The master of all things "power" in your engine.
• In the end, what really matters is the number of oxygen molecules in the combustion chamber (provided you have enough fuel to use it.)
• With an increase in pressure, the number of molecules goes up due to squeezing more air in a smaller space.
• The term Partial Pressure is in reference to the pressure of the Oxygen as a percentage of total volume. So, in air at sea level the Partial Pressure is .21 or 21% of total volume at 1 Atmosphere. If you boost to 14.7 PSI, or 2 Atmospheres, the partial pressure is going to double to .42, since you have twice as many oxygen molecules per volume.
• This "extra" oxygen is what provides the extra power and why Forced Induction can make a small engine perform like a much larger one. You see, you do not need extra PRESSURE to make more power, you need more PPO2.
• You can get it from pressurizing the intake, or from increasing the Oxygen content in the engine (vis-à-vis Nitrous).
• Remember the General Gas Law, since you will heat the mixture while you pressurize it, 14.7 PSI of boost is not exactly .42 PPO2 since it would heat up and become less dense. The fine details are more complicated, but the theory is - plan for, fuel for, tune for, EVERYTHING for PPO2, that is absolute unlike other strategies.
• General Gas Law – In any gas (liquid is a gas or gas is a liquid and they are both fluids; you pick), the combination of volume, pressure and temperature are related. A change in any one will affect a corresponding change in the others.
• Pressure and Volume are inversely related (Volume up, Pressure down),
• Volume and Temperature are inversely related (Volume Up, Temperature Down)
• Pressure and Temperature are proportional (Pressure Up, Temperature Up).
Cont.
• Pressure Gradient - Picture that old Jr. High Science Class Exp. No, not the girl who first let you touch her boob, focus! The one where you have two cups of liquid and a hose between them, lift one cup and the liquid will flow into the other (lower) cup. This is a good demonstration of a pressure gradient. Simply put, air is going to flow from the higher pressure, into the lower pressure.
• So in your engine cycle, the intake pressure is higher which moves the air into the cylinder. After combustion the expanded exhaust gas pressure is higher than the pressure in the exhaust so the air moves into the exhaust.
• The higher the "high" pressure / the lower the "low" pressure are, affects the velocity of that air movement. In boosted applications, this air is moving faster due to an increased pressure gradient.
Some More…
• Partial Pressure of Oxygen (PPO2) - The master of all things "power" in your engine.
• In the end, what really matters is the number of oxygen molecules in the combustion chamber (provided you have enough fuel to use it.)
• With an increase in pressure, the number of molecules goes up due to squeezing more air in a smaller space.
• The term Partial Pressure is in reference to the pressure of the Oxygen as a percentage of total volume. So, in air at sea level the Partial Pressure is .21 or 21% of total volume at 1 Atmosphere. If you boost to 14.7 PSI, or 2 Atmospheres, the partial pressure is going to double to .42, since you have twice as many oxygen molecules per volume.
• This "extra" oxygen is what provides the extra power and why Forced Induction can make a small engine perform like a much larger one. You see, you do not need extra PRESSURE to make more power, you need more PPO2.
• You can get it from pressurizing the intake, or from increasing the Oxygen content in the engine (vis-à-vis Nitrous).
• Remember the General Gas Law, since you will heat the mixture while you pressurize it, 14.7 PSI of boost is not exactly .42 PPO2 since it would heat up and become less dense. The fine details are more complicated, but the theory is - plan for, fuel for, tune for, EVERYTHING for PPO2, that is absolute unlike other strategies.
You judge the COMPRESSOR's on pressure and flow because that is what they do - make air at XYZ pressure ratio. You judge the fit to the motor based on mass air flow.... pressure only matters for determining dynamic compression and hence timing, and fueling to a small extent.
You have to think about them all as related components - never mind turbine spool (for turbo's)..... that adds even more into the mix.
"No, not the girl who first let you touch her boob, focus! The one where you have two cups of liquid and a hose between them "
See - you stuffed the whole thing up for me here . All I could think about was the girl with cups on her ***** and a hose between them .
See - you stuffed the whole thing up for me here . All I could think about was the girl with cups on her ***** and a hose between them .
HAHA - Good one.
Registered
Joined: Sep 2007
Posts: 191
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From: Houston, TX
Ya I am very happy with the III's. Tirerack had them in a higher category than the II's as well (Like High Performance Summer [II] vs Max Performance Summer [III] or something like that). Originally I ordered General Exclaim UHP, but Vance from Tirerack called me up to confirm/discuss my sizing choice, and ended up talking me into them. Very happy he did.
They didnt spin even at 12 psi. Not sure I attempted it in 1st, just use that to get rolling. 2nd didn't have a problem with traction that I can recall, but 3rd onward absolutely had zero problems with traction at full boost for sure.
The only question is, how long will they last. They are sticky as hell, so the life span is probably sacrificed. I'll let everyone know when I've used them up. At 10K miles on that set so far (aggressive driving / no track).
If anyone is interested, the testimonials from owners were compelling:
http://www.tirerack.com/tires/tires....e1=yes&place=0
They didnt spin even at 12 psi. Not sure I attempted it in 1st, just use that to get rolling. 2nd didn't have a problem with traction that I can recall, but 3rd onward absolutely had zero problems with traction at full boost for sure.
The only question is, how long will they last. They are sticky as hell, so the life span is probably sacrificed. I'll let everyone know when I've used them up. At 10K miles on that set so far (aggressive driving / no track).
If anyone is interested, the testimonials from owners were compelling:
http://www.tirerack.com/tires/tires....e1=yes&place=0
except in this case a number of you are in mass-ive fail mode
he stated it as clearly as anyone who understands the basic laws of gases needs to hear
Based on your compressed air theory, you might as well pull your intercooler off. Heck, you'll see an immediate boost gain of several psig, except you can then explain to us why you're making significantly less power rather than the same or more.
WTF ? Did you read what I said ?