View Poll Results: Which setup is better in your opinion?
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procharge vs turbo vs super
06-02-2008, 07:44 PM
#76
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as far as gas millage goes, I am getting 34 miles on the highway now. I am a huge fan of the tvs. but the only problem I have with thte supercharger right now, is that its not making the power that I want to reach. that is my only reason for contemplating a turbo swap. If you want power, then I would stop worring about gas milage so much because its gunna take fuel to produce the power your looking to achieve.
06-02-2008, 09:02 PM
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I cannot agree. The backpressure a turbo adds at cruise speeds, which consume approximately 1/10th of the engine's overall airflow potential, is inconsequential at best. Bear in mind how little airflow the car is actually using during cruise. It's nowhere near enough for the turbocharger to induce a significant pumping loss or restriction.
We've not seen the same reports of increased fuel economy with superchargers, and we attribute this to the fact that the turbocharger is using otherwise un-utilized exhaust gas heat energy to help overcome pumping losses at cruise, as opposed to a parasitic loss off the crankshaft via a belt drive like a supercharger. The supercharger always requires additional fuel consumption to operate. With the turbo, it's essentially a bonus of converting some of that otherwise wasted energy into cruising efficiency gains.
Additionally, the linear air delivery of superchargers versus RPM means that, unlike turbos, thay are not load-sensitive, and rely on additional devices such as supercharger bypass valves to discourage boost pressure during light throttle acceleration. This does nothing except pump the same air through the super more than once, which wastes energy and adds heat. Turbo cars are not subject to such inefficient 'recycling' of air during cruise. Additionally, their ability to infinitely respond to varying load conditions makes them much more effective, providing minimal airflow (as compared to a super) that results in improved fuel economy during light throttle commuting and cruising conditions.
We've not seen the same reports of increased fuel economy with superchargers, and we attribute this to the fact that the turbocharger is using otherwise un-utilized exhaust gas heat energy to help overcome pumping losses at cruise, as opposed to a parasitic loss off the crankshaft via a belt drive like a supercharger. The supercharger always requires additional fuel consumption to operate. With the turbo, it's essentially a bonus of converting some of that otherwise wasted energy into cruising efficiency gains.
Additionally, the linear air delivery of superchargers versus RPM means that, unlike turbos, thay are not load-sensitive, and rely on additional devices such as supercharger bypass valves to discourage boost pressure during light throttle acceleration. This does nothing except pump the same air through the super more than once, which wastes energy and adds heat. Turbo cars are not subject to such inefficient 'recycling' of air during cruise. Additionally, their ability to infinitely respond to varying load conditions makes them much more effective, providing minimal airflow (as compared to a super) that results in improved fuel economy during light throttle commuting and cruising conditions.
The whole problem comes in where its much harder for most people to visualize the power and efficiency of a turbo system because it takes some knowedge of thermodyamics to understand.. much easier for the average joe to see a belt
I'll start with some basic full load calcs (all verified with data)
Lets look at turbo efficiency
turbine isentropic effiency = 65%
Mechanical efficiency = 96-97%
Compressor isentropic efficiency = 75%
Total system efficiency 65%*97%*75% = 47.2%
Now look at supercharger efficiency
Belt efficiency 98%
Mechanical Efficiency 95-96%
Compressor isentropic effciency= 75%
Total system Efficency = 98*95*75 = 69%
So basicaly for each amount of energy placed into the unit, the supercharger system utilizes it more efficiently. How can this be?
Well we all know where supercharger and turbochargers get their engergy. both systems require LOTS of energy.. i dont care if its a turbo or supercharger.. if the compressor side has equal efficiency, pressure ratio, and mass flow they require THE SAME POWER to run. Now we agree on that.. we need to look at how you get the energy
the supercharger gets its energy from the belt (we all agree), However, what you dont see is the POSITIVE pumping work (intake pressure always much greater than exhaust pressure) this positive pumping work can account for quite a few HP.
Turbocharger gets its energy from Enthapy in the exhaust stream (basically Enthalpy is a product of temperature and pressure). So this means that the exhaust heat is the only area of energy that a turbo can acquire that a supercharger cannot. If it wasnt for heat, the turbocharger would rely solely on pressure.. (reason why i would never buy an STS turbo kit.. but i digress) So the heat energy has to be enough to overcome to total system inefficiency of the turbo itself..
So depending on the system either the turbocharger and the supercharger have the ability to make the engine more fuel efficient than the other boosting device.
Now it comes down to the issue of boost response and its effect on fuel economy. You need to look at transmission calibration on this one. Lets say we have equal BSFC maps for the two engines (one sc and one tc). Also, both have the same FMEP (friction) curves. (discounting knock inefficiency) you want to keep the engine spinning as slow as possible becuase boost always costs less energy than spinning the engine faster. I'll take boost over RPM any day of the week for fuel efficiency.
So this begs the question.. How do you keep the engine spinning slow and still have power when you need it? We all understand turbo lag but how does this impact fuel economy? When doing transmission calibration you must match the desired acceleration to the proper operating condition of the engine. Now becuase most driving is transient, Time is always a factor.. If your turbo isnt spooling, you'll have to compensate for the lack of torque with engine rpm by choosing a lower gear (higher numerically). This choice sacrifices the friction power to the fuel economy gods.. Now if you have instant boost.. you can delay the downshift and still maintain the desired acceleration.
Well the cat's out of the bag.. We need a smaller turbo!! transient response DOES have an impact on fuel economy.. So now the smaller turbo is chosen.. Well initially thought to be a benefit, having the turbine in the exhaust stream now creates more backpressure during cruise because you cannot open the wastegate.. you'd have too much lag and defeat the purpose of the small turbine. just remember, it doesnt take much restriction to cause a drop in fuel economy (just a few kPa).. same reason free flowing exhaust benefits fuel economy.. and a turbine is the MOST restrictive muffler you can get!!
I can keep going.. but i believe my point is made..
I will leave it with a final statement about this topic of comparison.. with increases in efficiency of the superchargers and looking at the tradeoffs of both systems.. the playing field has been made level. I do agree that older ineffient superchargers could not compete.. To understand the total tradeoffs requires much more knowledge of the engine and its operating conditions than most have.. its definately NOT "SC robs power from crank and turbo's are free energy", like most believe..
Your theory about the turbo's benefit to fuel economy is not quite correct.. by the same token you could add a more restrictive muffler which makes you open the throttle more thus less manifold vaccum.. I dont disagree however that turbo systems can be made to benefit fuel economy, but thats not the reason.
Im not trying to be for or against you here, just want to state the facts in the auto industry.. (and since you're pro turbo.. i like to play devils advocate, i can appreciate both very much)
06-02-2008, 09:05 PM
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so much misinformation in this thread... a procharger is a centrifugal supercharger... what kind of supercharger is the supercharger option? roots/centri/twin screw? you will get the best track times with a turbo. Centrifugal is kinda stupid on a four cylinder imo because you don't have the kind of low end torque you are gonna want to have to make the most out of the power delivery of a centri. The roots is just damned inefficient. I say either twin screw or turbo. If you are just a daily driver that you want fun power on and maybe go to the track sometimes id personally go twin screw...you want the best performance period...turbo.
06-02-2008, 09:13 PM
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so much misinformation in this thread... a procharger is a centrifugal supercharger... what kind of supercharger is the supercharger option? roots/centri/twin screw? you will get the best track times with a turbo. Centrifugal is kinda stupid on a four cylinder imo because you don't have the kind of low end torque you are gonna want to have to make the most out of the power delivery of a centri. The roots is just damned inefficient. I say either twin screw or turbo. If you are just a daily driver that you want fun power on and maybe go to the track sometimes id personally go twin screw...you want the best performance period...turbo.
06-02-2008, 09:15 PM
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what? you think he isn't going to have the best track times with a proper turbo setup? You don't think the roots is going to be inefficient at the power level these other options can produce? You think a centrifugal blower is a good setup on an lsj?
edit: forgot the tvs was out for these cars. tvs or twin screw for fun daily driver. turbo for track.
edit: forgot the tvs was out for these cars. tvs or twin screw for fun daily driver. turbo for track.
06-02-2008, 09:21 PM
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what? you think he isn't going to have the best track times with a proper turbo setup? You don't think the roots is going to be inefficient at the power level these other options can produce? You think a centrifugal blower is a good setup on an lsj?
edit: forgot the tvs was out for these cars. tvs or twin screw for fun daily driver. turbo for track.
edit: forgot the tvs was out for these cars. tvs or twin screw for fun daily driver. turbo for track.
06-02-2008, 09:22 PM
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06-03-2008, 12:26 PM
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I'm sorry you do not agree. however, what i stated has been proven. I agree the supercharger uses a bypass valve to eliminate boost.. however do you know how much power it takes at a highway cruise speed? in a properly designed system.. about 1/3 hp. Now your 'inconsequential' restriction on the exhaust can account for the same drag through increases to PMEP.
The whole problem comes in where its much harder for most people to visualize the power and efficiency of a turbo system because it takes some knowedge of thermodyamics to understand.. much easier for the average joe to see a belt
I'll start with some basic full load calcs (all verified with data)
Lets look at turbo efficiency
turbine isentropic effiency = 65%
Mechanical efficiency = 96-97%
Compressor isentropic efficiency = 75%
Total system efficiency 65%*97%*75% = 47.2%
Now look at supercharger efficiency
Belt efficiency 98%
Mechanical Efficiency 95-96%
Compressor isentropic effciency= 75%
Total system Efficency = 98*95*75 = 69%
So basicaly for each amount of energy placed into the unit, the supercharger system utilizes it more efficiently. How can this be?
Well we all know where supercharger and turbochargers get their engergy. both systems require LOTS of energy.. i dont care if its a turbo or supercharger.. if the compressor side has equal efficiency, pressure ratio, and mass flow they require THE SAME POWER to run. Now we agree on that.. we need to look at how you get the energy
the supercharger gets its energy from the belt (we all agree), However, what you dont see is the POSITIVE pumping work (intake pressure always much greater than exhaust pressure) this positive pumping work can account for quite a few HP.
Turbocharger gets its energy from Enthapy in the exhaust stream (basically Enthalpy is a product of temperature and pressure). So this means that the exhaust heat is the only area of energy that a turbo can acquire that a supercharger cannot. If it wasnt for heat, the turbocharger would rely solely on pressure.. (reason why i would never buy an STS turbo kit.. but i digress) So the heat energy has to be enough to overcome to total system inefficiency of the turbo itself..
So depending on the system either the turbocharger and the supercharger have the ability to make the engine more fuel efficient than the other boosting device.
Now it comes down to the issue of boost response and its effect on fuel economy. You need to look at transmission calibration on this one. Lets say we have equal BSFC maps for the two engines (one sc and one tc). Also, both have the same FMEP (friction) curves. (discounting knock inefficiency) you want to keep the engine spinning as slow as possible becuase boost always costs less energy than spinning the engine faster. I'll take boost over RPM any day of the week for fuel efficiency.
So this begs the question.. How do you keep the engine spinning slow and still have power when you need it? We all understand turbo lag but how does this impact fuel economy? When doing transmission calibration you must match the desired acceleration to the proper operating condition of the engine. Now becuase most driving is transient, Time is always a factor.. If your turbo isnt spooling, you'll have to compensate for the lack of torque with engine rpm by choosing a lower gear (higher numerically). This choice sacrifices the friction power to the fuel economy gods.. Now if you have instant boost.. you can delay the downshift and still maintain the desired acceleration.
Well the cat's out of the bag.. We need a smaller turbo!! transient response DOES have an impact on fuel economy.. So now the smaller turbo is chosen.. Well initially thought to be a benefit, having the turbine in the exhaust stream now creates more backpressure during cruise because you cannot open the wastegate.. you'd have too much lag and defeat the purpose of the small turbine. just remember, it doesnt take much restriction to cause a drop in fuel economy (just a few kPa).. same reason free flowing exhaust benefits fuel economy.. and a turbine is the MOST restrictive muffler you can get!!
I can keep going.. but i believe my point is made..
I will leave it with a final statement about this topic of comparison.. with increases in efficiency of the superchargers and looking at the tradeoffs of both systems.. the playing field has been made level. I do agree that older ineffient superchargers could not compete.. To understand the total tradeoffs requires much more knowledge of the engine and its operating conditions than most have.. its definately NOT "SC robs power from crank and turbo's are free energy", like most believe..
Your theory about the turbo's benefit to fuel economy is not quite correct.. by the same token you could add a more restrictive muffler which makes you open the throttle more thus less manifold vaccum.. I dont disagree however that turbo systems can be made to benefit fuel economy, but thats not the reason.
Im not trying to be for or against you here, just want to state the facts in the auto industry.. (and since you're pro turbo.. i like to play devils advocate, i can appreciate both very much)
The whole problem comes in where its much harder for most people to visualize the power and efficiency of a turbo system because it takes some knowedge of thermodyamics to understand.. much easier for the average joe to see a belt
I'll start with some basic full load calcs (all verified with data)
Lets look at turbo efficiency
turbine isentropic effiency = 65%
Mechanical efficiency = 96-97%
Compressor isentropic efficiency = 75%
Total system efficiency 65%*97%*75% = 47.2%
Now look at supercharger efficiency
Belt efficiency 98%
Mechanical Efficiency 95-96%
Compressor isentropic effciency= 75%
Total system Efficency = 98*95*75 = 69%
So basicaly for each amount of energy placed into the unit, the supercharger system utilizes it more efficiently. How can this be?
Well we all know where supercharger and turbochargers get their engergy. both systems require LOTS of energy.. i dont care if its a turbo or supercharger.. if the compressor side has equal efficiency, pressure ratio, and mass flow they require THE SAME POWER to run. Now we agree on that.. we need to look at how you get the energy
the supercharger gets its energy from the belt (we all agree), However, what you dont see is the POSITIVE pumping work (intake pressure always much greater than exhaust pressure) this positive pumping work can account for quite a few HP.
Turbocharger gets its energy from Enthapy in the exhaust stream (basically Enthalpy is a product of temperature and pressure). So this means that the exhaust heat is the only area of energy that a turbo can acquire that a supercharger cannot. If it wasnt for heat, the turbocharger would rely solely on pressure.. (reason why i would never buy an STS turbo kit.. but i digress) So the heat energy has to be enough to overcome to total system inefficiency of the turbo itself..
So depending on the system either the turbocharger and the supercharger have the ability to make the engine more fuel efficient than the other boosting device.
Now it comes down to the issue of boost response and its effect on fuel economy. You need to look at transmission calibration on this one. Lets say we have equal BSFC maps for the two engines (one sc and one tc). Also, both have the same FMEP (friction) curves. (discounting knock inefficiency) you want to keep the engine spinning as slow as possible becuase boost always costs less energy than spinning the engine faster. I'll take boost over RPM any day of the week for fuel efficiency.
So this begs the question.. How do you keep the engine spinning slow and still have power when you need it? We all understand turbo lag but how does this impact fuel economy? When doing transmission calibration you must match the desired acceleration to the proper operating condition of the engine. Now becuase most driving is transient, Time is always a factor.. If your turbo isnt spooling, you'll have to compensate for the lack of torque with engine rpm by choosing a lower gear (higher numerically). This choice sacrifices the friction power to the fuel economy gods.. Now if you have instant boost.. you can delay the downshift and still maintain the desired acceleration.
Well the cat's out of the bag.. We need a smaller turbo!! transient response DOES have an impact on fuel economy.. So now the smaller turbo is chosen.. Well initially thought to be a benefit, having the turbine in the exhaust stream now creates more backpressure during cruise because you cannot open the wastegate.. you'd have too much lag and defeat the purpose of the small turbine. just remember, it doesnt take much restriction to cause a drop in fuel economy (just a few kPa).. same reason free flowing exhaust benefits fuel economy.. and a turbine is the MOST restrictive muffler you can get!!
I can keep going.. but i believe my point is made..
I will leave it with a final statement about this topic of comparison.. with increases in efficiency of the superchargers and looking at the tradeoffs of both systems.. the playing field has been made level. I do agree that older ineffient superchargers could not compete.. To understand the total tradeoffs requires much more knowledge of the engine and its operating conditions than most have.. its definately NOT "SC robs power from crank and turbo's are free energy", like most believe..
Your theory about the turbo's benefit to fuel economy is not quite correct.. by the same token you could add a more restrictive muffler which makes you open the throttle more thus less manifold vaccum.. I dont disagree however that turbo systems can be made to benefit fuel economy, but thats not the reason.
Im not trying to be for or against you here, just want to state the facts in the auto industry.. (and since you're pro turbo.. i like to play devils advocate, i can appreciate both very much)
When I see anything else, I'll believe it! As for now, this is reality.
06-03-2008, 12:37 PM
#84
i say turbo.. even though i'm going procharged.. sheerly because your stock compression seems too low to run a procharger effectively you'll get gains.. but not huge ones.. unless you go with a big ass blower.
there are alot of reasons i went with a procharger and I know it's not the best for power but it fits what i want
there are alot of reasons i went with a procharger and I know it's not the best for power but it fits what i want
06-03-2008, 01:14 PM
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Turbocharged cars using today's technology get better fuel mileage than supercharged cars, whether you like it or not. Hinting at mysterious 'new technology' that's going to 'level the playing field' is, for the purposes of everyone reading this thread, one step short of science fiction, for these good folks are all using...today's technology...as are the legions of automotive engineers currently designing turbocharged applications to introduce in the model years to come.
When I see anything else, I'll believe it! As for now, this is reality.
When I see anything else, I'll believe it! As for now, this is reality.
Same class, both manual trans, both 1.8L, same size approx
Only difference is Audi is FWD and Mercedes is RWD
Keep in mind, this mercedes is using the "Old inefficient" roots type.. as what you would consider 'todays' technology.. as well as audi is using todays technology turbocharger...
Only difference is 1mpg highway.. mainly atributed to RWD.. but also shows how close they truly are. Thats my whole point... things when done properly are alot closer than you think...
So what happens if superchargers get more efficient?
Now for the funny part.. Everyone claims downsizing, direct injection, and Turbo's are the future..
check this out
Mazda Cx7 2.3L Turbo
Chevy Equinox 3.6L NA
So just having a smaller engine with direct injection and turbo doesnt mean good fuel economy... The poor turbo engine gets worse fuel economy than a significantly larger V6
So in the end.. i am fairly certain there are many options to get the fuel economy you desire.. So please, dont jump to conclusions
like i said before, i state the facts of the automotive industry. I look at things in detail and try to account for ALL variables.
If you want to compare steady state operating points and optimize a turbo for that point.. i'll agree with you to some extent... but life is alot more complicated than that
Last edited by TVS_SS; 06-03-2008 at 01:32 PM.
06-03-2008, 02:50 PM
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You know, I like this site you brought up!
I decided to pick something more relevant to this forum, something a little less 'apples to oranges'. So I looked up a Supercharged 2007 Cobalt against a Turbocharged 2008 Cobalt.
What could be more relevant...same car, same engine displacement, same driveline, but one KEY difference...one is turbocharged, the other supercharged. So, what do we see but...
...a 10% difference in fuel economy!
Yep, the Direct Injected, Turbocharged Cobalt gets better fuel mileage than the supercharged one, and they are both using contemporary, available now technology.
Great site d00d!
I decided to pick something more relevant to this forum, something a little less 'apples to oranges'. So I looked up a Supercharged 2007 Cobalt against a Turbocharged 2008 Cobalt.
What could be more relevant...same car, same engine displacement, same driveline, but one KEY difference...one is turbocharged, the other supercharged. So, what do we see but...
...a 10% difference in fuel economy!
Yep, the Direct Injected, Turbocharged Cobalt gets better fuel mileage than the supercharged one, and they are both using contemporary, available now technology.
Great site d00d!
06-03-2008, 03:17 PM
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The turbo cobalt benefits from direct injection, Variable valve timing, lower final drive ratio etc.. The 10% does not come from the turbo..
This is not apples to apples..
Heck this whole time i've been stating final drive ratio and the spark timing optimization as the key to fuel economy.. thats exactly what GM did with the SS/TC.. could you do the same with a supercharged version? You bet!
and the SS/SC still has the 1970's style vaccum bypass actuator, Laminova intercoolers, 4.05 final drive.. its not hard to get better fuel economy if your competition has this holding it back.... im just surprised the turbo engine only beat it by 10%..lol
(edit, technically its only 8.7% better.. but hey, rounding sounds better..)
I understand if proving turbo's dominate the world helps you sleep better.. but again, facts are facts, both systems can be made very fuel efficient. And if you cant look beyond the turbo's are free energy thats fine. I have dealt with the industries finest on both sides of the fence and both systems have huge flaws, My biggest problem is there there isnt a perfect boosting system...
Are there applications where superchargers get better fuel economy? yes
Are there applications where turbocharger get better fuel economy? yes
Are the differences in fuel economy alot smaller than the turbo industry would like you to believe? yes
If you dont agree then you have officially become a 'salesman' rather than an 'engineer'
I can make enough logical arguments to prove either one is better than the other... But at the end of the day, i'd rather have a good system than jump on a bandwagon because they are popular and have been marketed well..
Last edited by TVS_SS; 06-03-2008 at 03:45 PM.
06-03-2008, 03:20 PM
#90
it sc is such the way to go .. then why are there so many more stock turbo cars? sc doesn't give the most power nor is it the most economical... hell even saturn is doing a 1.4 L turbo engine in a few years so it can have goo gas mileage and decent power
06-03-2008, 03:26 PM
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06-03-2008, 03:27 PM
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lol **** it, fully forge the motor and spray the **** outta it lol then maybe if your lucky enough itll blow up hahaha (i was being sarcastic with that)
turbo is my opinion since i dont like to lose some power on a belt to gain power
turbo is my opinion since i dont like to lose some power on a belt to gain power
06-03-2008, 03:29 PM
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You also said...
How do you like THEM apples! Watching you play both sides of the direct-injection debate just nails it!
06-03-2008, 03:57 PM
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you guys aren't proving **** to each other...every single on of these have been different by no more than 1 mpg...**** have the epa test em again and they may be slightly different.
Fact- nobody here gives enough of a flying **** to decide between blower and turbo because of 1-2mpg bump in fuel economy. Stop arguing a moot point.
Fact- nobody here gives enough of a flying **** to decide between blower and turbo because of 1-2mpg bump in fuel economy. Stop arguing a moot point.
06-03-2008, 04:06 PM
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This gives a total possible difference (again, just using the data you brought to the discussion) of almost 13% (which is rounding up from 12.8).
you guys aren't proving **** to each other...every single on of these have been different by no more than 1 mpg...**** have the epa test em again and they may be slightly different.
Fact- nobody here gives enough of a flying **** to decide between blower and turbo because of 1-2mpg bump in fuel economy. Stop arguing a moot point.
Fact- nobody here gives enough of a flying **** to decide between blower and turbo because of 1-2mpg bump in fuel economy. Stop arguing a moot point.
Better gain than most Certificates of Deposit, and you only have to tie up one tankful of ca$h at a time!Fun thing is...If you look further down, you'll see in real world results ('drivers like you') that the heavier turbo car even pulls ahead, 31 MPG to 30 MPG. Naturally!
Last edited by Hahn RaceCraft; 06-03-2008 at 04:12 PM. Reason: Automerged Doublepost
06-03-2008, 04:22 PM
#97
True enough. Fact is, EPA also rounded their numbers to the nearest MPG, as did I, so the SC could have been as low as 22.5, and the turbo as high as 25.4.
This gives a total possible difference (again, just using the data you brought to the discussion) of almost 13% (which is rounding up from 12.8).
No, actually, 2 MPG out of 20-ish is significant. That's one free mile for every ten traveled. Or an extra buck saved for every ten spent. Better gain than most Certificates of Deposit, and you only have to tie up one tankful of ca$h at a time!
Well, according to TVS' standards, comparing different cars is more accurate than comparing the same car, so...why not?
Fun thing is...If you look further down, you'll see in real world results ('drivers like you') that the heavier turbo car even pulls ahead, 31 MPG to 30 MPG. Naturally!
This gives a total possible difference (again, just using the data you brought to the discussion) of almost 13% (which is rounding up from 12.8).
No, actually, 2 MPG out of 20-ish is significant. That's one free mile for every ten traveled. Or an extra buck saved for every ten spent.
Better gain than most Certificates of Deposit, and you only have to tie up one tankful of ca$h at a time!Well, according to TVS' standards, comparing different cars is more accurate than comparing the same car, so...why not?
Fun thing is...If you look further down, you'll see in real world results ('drivers like you') that the heavier turbo car even pulls ahead, 31 MPG to 30 MPG. Naturally!
06-03-2008, 04:49 PM
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Edit:
Bill, if you want to win this internet argument, i'll let you
Any good engineer isnt one sided on an argument... But a good salesman is!!
"It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
Bill, if you want to win this internet argument, i'll let you
Any good engineer isnt one sided on an argument... But a good salesman is!!
"It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
Last edited by TVS_SS; 06-03-2008 at 05:52 PM.
06-03-2008, 05:07 PM
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or you can just look at the application (in this case an ss/sc) and tell him what will be better in what situations and then he can decide from there. I don't think he really wants to hear about the adiabatic efficiency of the four options.
06-03-2008, 06:53 PM
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Oh gosh. I just won the Special Olympics! *runs to short bus*
Nah, no need to declare a winner, although I appreciate the gesture. I felt it was all thought-provoking stuff on both sides, so everybody wins!
All in good fun! You know what they say, 'It's not the kill, but the thrill of the chase.' Thanks for the sparring session!
Nah, no need to declare a winner, although I appreciate the gesture. I felt it was all thought-provoking stuff on both sides, so everybody wins!
All in good fun! You know what they say, 'It's not the kill, but the thrill of the chase.' Thanks for the sparring session!