STS Thread

[Sam1647545489]

http://smiliesftw.com/x/hsughugh.gif

 

 

http://forums.offtopic.com/images/smilies/kekekegay.gif

[Sam1647545489]

P.S. Austin find a new server cause your smiley is taking forever to load.

[RedRocket1647545505]

P.S. Austin find a new server cause your smiley is taking forever to load.

 

My shit's always slow.

[Sam1647545489]

I make 148k/yr and drive an 02 cougar...

[coltboostin]

You have too much time on your hands. Go do something constructive.

 

+1

 

If it takes me more than 3 seconds to scroll through a post-it only tell me someone (the original poster) has not gotten laid in a long fucking time.

 

 

Jesus H Christ-the internet is SERIOUS!

[Linn1647545492]

yes to both questions - why can't an engine with a turbocharger have a linear output? Lingenfelter is a great example of a company that strives for it. you simply cant extract the same amount of power (under the curve) no matter what compression or rev limit doller per doller compared to a properly built turbo car.

 

now we're adding a caveat that the application is for drag/roll racing...

 

Lingenfelter also uses turbos that choke the motor, which is why all their car lose power above 5900rpm.

[Cougar1647545494]

Lingenfelter also uses turbos that choke the motor, which is why all their car lose power above 5900rpm.

 

if full power comes on at 3000, and the appropriate rear end gear is run, that equates to more total area under the curve then a slim lsa "peaky" high compression motor.

[Kevin R.]

Can you get an interpretor? You are just too smart for me to read your posts.

[Linc5.0]

Can you get an interpretor? You are just too smart for me to read your posts.

http://i40.photobucket.com/albums/e233/stephaniegt/ShortBus.gifj/k Kevin

[Cougar1647545494]

Can you get an interpretor? You are just too smart for me to read your posts.

 

i like your sig pic, it makes me laugh

[Miller]

kevin drinks like a girl

[Nate1647545505]

Chris --Like Phil(Mallard) said, don't take things so seriously here. You arent infront of a research board or some overpaid mananger - you're on a public forum.

 

You suond like a huge dick on some of these posts, what goes around tends to come around.

[Nitrousbird]

I make 148k/yr and drive an 02 cougar...

We should all get 3 of them.

[Alex1647545498]

since the other places to discuss it were inappropriate, here it is.

 

lets take a look at their faq, and put it up against the wall of basic thermo, fluid dynamic principles, shall we?

 

 

heat is energy. heat in a closed system won't make volume, it'll make pressure... a means of storing energy.

 

 

 

 

volume between the cylinder head and the turbo is somewhat fixed... that makes it a variable that isn't. so an increase in temperature will cause a corresponding increase in pressure. either way, its energy.

 

 

conservation of mass applies here. The mass flow rate is equal to the density times the velocity times the flow area.

if we hold mass flow rate as constant and flow area constant, we see that velocity is inversely proportional to density.

conservation of momentum also applies.

also, for isentropic flow, change in pressure is equal to change in density times the speed of sound squared.

so if velocity goes up, pressure goes down... not up.

 

 

aren't we still in the exhaust, where's this extra "volume" coming from?

 

 

 

mass flow. also, see nozzle physics above

 

 

trucks are 1+ feet in the air. plenty of ambient air around it. A car is much lower. In most sports cars, you'd have that pipe near the exhaust tunnel. The airflow it will recieve will be the heat wash off of the radiator, engine, and exhaust. its warm down there.

 

heat exchange rate is largely dependent on temperature difference between the various media. you'd need the air outside the pipe to be meaningfully cooler than the air inside the pipe. you'd also need good contact between most of the air in the pipe and the pipe, which generally means small fins and a lot of surface area. you then need similar radiative area.

their best numbers (which are probably the ones they'd post) will be with cold pipes. heat absorbtion with aluminum pipes is one thing. dumping that heat back out is another. ideally, IC efficency should be measured not as a peak.

they are probably heavily reliant on building heat in the exhaust to make that side of things work, but also heavily reliant on not building heat in the charge pipe. you might see how those are against each other.

 

 

is that a "well, it could be worse" answer? 10 feet of pipe is 10 feet of pipe.

at a given pressure, the greater the flow the greater the loss per foot of pipe.

 

 

numbers are good. numbers are even better when they have the right information attached to them for them to actually mean something.

Using the right units would probably be helpful too.

 

 

 

turbos being hot and the gasses being hot are *slightly* different concepts. As per the links i provided, the turbine is driven by energy. change in total energy across the turbine tells you what energy has gone into turning the turbine. less heat means less energy available to turn it.

 

 

 

NO! airflow doesn't do it. you can't run a steam turbine on the same mass flow of lukewarm water. ENERGY spins the turbine.

 

 

 

 

methanol burning cars and diesel trucks have similar peak EGT ranges. they also usually have "small" turbos for their displacement. both are generally fairly slow to come on boost still, especially given their usual power goals. methanol race cars end up running a lot of boost and size most of the turbo bits around that (or the rules). diesels shouldn't be directly compared as they are a very different beast. for a diesel, boost doesn't make power, it makes safety. they can make the power without the boost in most cases, just not for very long before something goes boom.

 

 

 

i know they've seen the PV=nRT equation before. They even tried using it. someone should explain to them how it works. honestly, them not getting this right is depressing. V is the volume... of the VESSEL.

The heat doesn't cause the "air molecules" to seperate, it causes them to move faster. temperature is a measure of internal energy. the exhaust manifold is a relatively fixed volume, so if we're going to assume that we can apply the ideal gas laws, we can assume that the increase in temp will be an increase in pressure. (or that a decrease in temp will have a corresponding decrease in pressure.)

 

 

 

again, an example of complete misunderstanding.

yes, heat energy is lost. mass flow is the same. mass flow rate is the same.

you are driving the turbine with cooler air, and thus less energy.

 

 

 

go tell a power plant engineer to use cooler steam to drive his turbines because cooler is better.

 

 

 

the volume isn't bigger when the exhaust system is shorter.

saying that there is less backpressure caused by the smaller housing with the cooler gasses is very misleading as well.

 

 

highlighting compromises that shouldn't be made.

 

 

 

again more misunderstanding and BS. engine temp and EGT are VERY unrelated. chances are that an STS or any other rearmount will have significantly more lag while the car (and exhaust) isn't up to temp though. probably a "other turbo cars are like that too" smoke and mirrors attempt at saving face when some customers call and complain.

 

 

is there a "sized correctly" on an improperly placed turbo?

 

 

 

 

generalities....

 

 

they don't understand flow through a nozzle well either.

 

 

bigger pipes pre turbo increases the volume and surface area. that'd hurt even worse.

 

 

so once all of the exhaust is glowing hot (as to minimize heat loss) its good to go. before that, good luck getting it to do anything...

on a *not 14 feet from the engine* turbocharger, there is no waiting for your exhaust to heat up.

 

 

 

they use very small housings. we get it. doesn't mean it won't work up front. it'd spool markedly faster closer to the engine.

 

 

i think there are a lot of issues at play here. one is understanding of physics. the other is expectations and experience. if you've never been in a responsive vehicle, you don't realize how unresponsive something else may be.

 

i will say that it is one thing to discuss details of turbine energy collection and something else entirely to get it completely wrong. especially the basic physics side of things.

 

innovation implies something new. there's nothing "new" about doing something the wrong way. in general, you *try* to place the turbine as close to the energy source as possible. there are often compromises that must be made that force you to put it slightly farther than you may otherwise like. taking that and intentionally putting it as far from the energy source as possible isn't "innovative" so much as unintelligent.

 

it'd be like walking up to the plate in baseball and thinking "everyone else here is trying to hit that white ball they throw at you... but i'm going to be different.i'll not hit it and see what happens." if you stand there and don't swing, and they walk you, does that mean its a good approach and a "proven" technique?

 

numbers themselves can be made to be decent. especially for one pull on a dyno. we've always known that peak numbers mean nothing. we also know that a dyno can't tell you how responsive an engine may or may not be. transitions, drivability, and responsiveness are the bits most in question here.

the efficency of the system isn't in question as we know that will be bad.

 

since the other places to discuss it were inappropriate, here it is.

 

lets take a look at their faq, and put it up against the wall of basic thermo, fluid dynamic principles, shall we?

 

 

heat is energy. heat in a closed system won't make volume, it'll make pressure... a means of storing energy.

 

 

 

 

volume between the cylinder head and the turbo is somewhat fixed... that makes it a variable that isn't. so an increase in temperature will cause a corresponding increase in pressure. either way, its energy.

 

 

conservation of mass applies here. The mass flow rate is equal to the density times the velocity times the flow area.

if we hold mass flow rate as constant and flow area constant, we see that velocity is inversely proportional to density.

conservation of momentum also applies.

also, for isentropic flow, change in pressure is equal to change in density times the speed of sound squared.

so if velocity goes up, pressure goes down... not up.

 

 

aren't we still in the exhaust, where's this extra "volume" coming from?

 

 

 

mass flow. also, see nozzle physics above

 

 

trucks are 1+ feet in the air. plenty of ambient air around it. A car is much lower. In most sports cars, you'd have that pipe near the exhaust tunnel. The airflow it will recieve will be the heat wash off of the radiator, engine, and exhaust. its warm down there.

 

heat exchange rate is largely dependent on temperature difference between the various media. you'd need the air outside the pipe to be meaningfully cooler than the air inside the pipe. you'd also need good contact between most of the air in the pipe and the pipe, which generally means small fins and a lot of surface area. you then need similar radiative area.

their best numbers (which are probably the ones they'd post) will be with cold pipes. heat absorbtion with aluminum pipes is one thing. dumping that heat back out is another. ideally, IC efficency should be measured not as a peak.

they are probably heavily reliant on building heat in the exhaust to make that side of things work, but also heavily reliant on not building heat in the charge pipe. you might see how those are against each other.

 

 

is that a "well, it could be worse" answer? 10 feet of pipe is 10 feet of pipe.

at a given pressure, the greater the flow the greater the loss per foot of pipe.

 

 

numbers are good. numbers are even better when they have the right information attached to them for them to actually mean something.

Using the right units would probably be helpful too.

 

 

 

turbos being hot and the gasses being hot are *slightly* different concepts. As per the links i provided, the turbine is driven by energy. change in total energy across the turbine tells you what energy has gone into turning the turbine. less heat means less energy available to turn it.

 

 

 

NO! airflow doesn't do it. you can't run a steam turbine on the same mass flow of lukewarm water. ENERGY spins the turbine.

 

 

 

 

methanol burning cars and diesel trucks have similar peak EGT ranges. they also usually have "small" turbos for their displacement. both are generally fairly slow to come on boost still, especially given their usual power goals. methanol race cars end up running a lot of boost and size most of the turbo bits around that (or the rules). diesels shouldn't be directly compared as they are a very different beast. for a diesel, boost doesn't make power, it makes safety. they can make the power without the boost in most cases, just not for very long before something goes boom.

 

 

 

i know they've seen the PV=nRT equation before. They even tried using it. someone should explain to them how it works. honestly, them not getting this right is depressing. V is the volume... of the VESSEL.

The heat doesn't cause the "air molecules" to seperate, it causes them to move faster. temperature is a measure of internal energy. the exhaust manifold is a relatively fixed volume, so if we're going to assume that we can apply the ideal gas laws, we can assume that the increase in temp will be an increase in pressure. (or that a decrease in temp will have a corresponding decrease in pressure.)

 

 

 

again, an example of complete misunderstanding.

yes, heat energy is lost. mass flow is the same. mass flow rate is the same.

you are driving the turbine with cooler air, and thus less energy.

 

 

 

go tell a power plant engineer to use cooler steam to drive his turbines because cooler is better.

 

 

 

the volume isn't bigger when the exhaust system is shorter.

saying that there is less backpressure caused by the smaller housing with the cooler gasses is very misleading as well.

 

 

highlighting compromises that shouldn't be made.

 

 

 

again more misunderstanding and BS. engine temp and EGT are VERY unrelated. chances are that an STS or any other rearmount will have significantly more lag while the car (and exhaust) isn't up to temp though. probably a "other turbo cars are like that too" smoke and mirrors attempt at saving face when some customers call and complain.

 

 

is there a "sized correctly" on an improperly placed turbo?

 

 

 

 

generalities....

 

 

they don't understand flow through a nozzle well either.

 

 

bigger pipes pre turbo increases the volume and surface area. that'd hurt even worse.

 

 

so once all of the exhaust is glowing hot (as to minimize heat loss) its good to go. before that, good luck getting it to do anything...

on a *not 14 feet from the engine* turbocharger, there is no waiting for your exhaust to heat up.

 

 

 

they use very small housings. we get it. doesn't mean it won't work up front. it'd spool markedly faster closer to the engine.

 

 

i think there are a lot of issues at play here. one is understanding of physics. the other is expectations and experience. if you've never been in a responsive vehicle, you don't realize how unresponsive something else may be.

 

i will say that it is one thing to discuss details of turbine energy collection and something else entirely to get it completely wrong. especially the basic physics side of things.

 

innovation implies something new. there's nothing "new" about doing something the wrong way. in general, you *try* to place the turbine as close to the energy source as possible. there are often compromises that must be made that force you to put it slightly farther than you may otherwise like. taking that and intentionally putting it as far from the energy source as possible isn't "innovative" so much as unintelligent.

 

it'd be like walking up to the plate in baseball and thinking "everyone else here is trying to hit that white ball they throw at you... but i'm going to be different.i'll not hit it and see what happens." if you stand there and don't swing, and they walk you, does that mean its a good approach and a "proven" technique?

 

numbers themselves can be made to be decent. especially for one pull on a dyno. we've always known that peak numbers mean nothing. we also know that a dyno can't tell you how responsive an engine may or may not be. transitions, drivability, and responsiveness are the bits most in question here.

the efficency of the system isn't in question as we know that will be bad.

 

Longest post evar!!!

 

Did anyone actually read through all that?

[JaSSon]

Longest post evar!!!

 

Did anyone actually read through all that?

 

Too long; didn't read.

[schmuckingham]

i made an honest attempt

[HAOLE]

I skimed through this thread and here is my .02.

 

I am not an engineer, but if the dyno says it makes power and the owner is happy. Who cares?

 

I am sure there is always someone that can build a better mouse trap, as long as the mice are dying the trap is working.

[TURBOED]

I skimed through this thread and here is my .02.

 

I am not an engineer, but if the dyno says it makes power and the owner is happy. Who cares?

 

I am sure there is always someone that can build a better mouse trap, as long as the mice are dying the trap is working.

 

I also skimmed through this thread....

 

I am a mechanical engineer. I graduated from a top 10 ME program, and I have a good job in the automotive industry. I have never been so insecure about myself to post 5,000 word essays on car forums to show everyone how much I know. I can almost understand posting all that crap if someone actually posed the question "Can someone please discuss the positives and negatives of xxx turbo system?" But seriously, posting that just for the benefit of all the "lowly non-engineers" is the most self-gratifying thing I have ever seen.

 

Oh, and as far as the mouse trap goes... sure, it's working if mice are dying, but there's always a more efficient way.

[phil]

nope couldnt do it to damd long

[Nate1647545505]

I don't think the motives were insecurity, he simply broke the STS FAQ down line by line to show it had more holes than swiss cheese. The responses are short and to the point.

 

He's the not the most polished applee when it comes to conveying information on a public forum, but there have been much worse on here.

 

Nate

[Draco-REX]

I'm not a fan of the tail-pipe turbos. There's no way it's more efficient or better than one at the engine, and I can't possibly see why it'd even equal a system with the same turbo up front.

 

If a tail-pipe system is the only way you can get it to fit, go right ahead, it's better than nothing.

 

But if you have the option to mount the turbo in a more conventional manner, do it. You'll have shorter intake pipes to pressurize and a faster spool which will give you more area under the torque curve.

[Nate1647545505]

I think that's the basis of his argument. Simply less energy.

 

With chassis like the F-Body or even Corvette, real estate is very tight. Granted on large displacement/low boost engines the system wouldn't be that bad of a compromise (life is made up of compromises). Keeping heat out of an engine bay not designed for a turbocharged engine is also a valid concern. The turbo M3's have a severe problem with underhood temperatures when road racing for decent periods.

 

Given how it's pretty easy to put a reasonably sized turbo (or two) in the engine bay of most vehicles and the availability of off the shelf manifolds makes it seem like a no brainer decision to go with the "technically advantageous" solution of putting the turbo as close as possible to the head IMO.

 

Nate

[V8 Beast]

Longest post evar!!!

 

Did anyone actually read through all that?

 

I cant read I only joined the forum to look at pictures of boobies

[phil]

I cant read I only joined the forum to look at pictures of boobies

 

 

http://i141.photobucket.com/albums/r43/jd_yall/l_829f726b3470c07a05c50b7b396178b9.gif

[Draco-REX]

http://i141.photobucket.com/albums/r43/jd_yall/l_829f726b3470c07a05c50b7b396178b9.gif

..and as far as the STS system goes..... BOOOOBIES!