Does HOTTER air BEFORE the turbine - cause faster spool
02-22-2005, 07:06 PM
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Does HOTTER air BEFORE the turbine - cause faster spool
This question came to mine while arguing with someone about the pro's and cons of a remote turbo system.
I have always been under the impression that HOT air wants to expand.
That being said; if it wants to expand and there is nowhere to go except for through the turbine, wouldn't the velocity of the air going through the turbine be greater, thus spooling the turbo faster.
I would like your educated opinions on this matter.
What probed this was:
quote: beepy
This just isn't true. Mass flow spools the turbo. In order for heat to spool the turbo the exhaust would have to come out of the downpipe at a much cooler temperature than the inlet to the turbo. Just doesn't happen.
If you were to push 300 lb/m of air through a turbine at 1500°F, then do the same test with 300 lb/m at 100°F, the results you would get would be close enough for approximation.
end quote.
this was a response to me asking : Don't you lose a LOT of heat on the way back to the turbo. . . heat spools the turbo
I know I should not have said heat spools the turbo - but I would say that it does HELP to spool the turbo IMO.
I have always been under the impression that HOT air wants to expand.
That being said; if it wants to expand and there is nowhere to go except for through the turbine, wouldn't the velocity of the air going through the turbine be greater, thus spooling the turbo faster.
I would like your educated opinions on this matter.
What probed this was:
quote: beepy
This just isn't true. Mass flow spools the turbo. In order for heat to spool the turbo the exhaust would have to come out of the downpipe at a much cooler temperature than the inlet to the turbo. Just doesn't happen.
If you were to push 300 lb/m of air through a turbine at 1500°F, then do the same test with 300 lb/m at 100°F, the results you would get would be close enough for approximation.
end quote.
this was a response to me asking : Don't you lose a LOT of heat on the way back to the turbo. . . heat spools the turbo
I know I should not have said heat spools the turbo - but I would say that it does HELP to spool the turbo IMO.
02-22-2005, 07:11 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (DragSource)
Interested in this topic!
I have heard that <U>both</U> flow and heat spool the turbine, but I want to learn more on why
I have heard that <U>both</U> flow and heat spool the turbine, but I want to learn more on why
02-22-2005, 07:16 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (DragSource)
"hot air" does not expand... the change in temperature going from cooler to hotter is what makes the air expand. the exhaust "air" comes out of the motor hot, when traveling down the manifold through the turbo and out the exhaust it's only cooling, so if anything it's compressing slightly.
However, gas comming out of a motor is traveling at a certain velocity, I think it's always true that the hotter the gas, the faster the velocity... this in turn spools the turbo faster
to answer the topic, yes the hotter air will cause faster spool because hotter air means it's traveling at a faster velocity.
Modified by turbosi03 at 11:27 PM 2/22/2005
However, gas comming out of a motor is traveling at a certain velocity, I think it's always true that the hotter the gas, the faster the velocity... this in turn spools the turbo faster
to answer the topic, yes the hotter air will cause faster spool because hotter air means it's traveling at a faster velocity.
Modified by turbosi03 at 11:27 PM 2/22/2005
02-22-2005, 07:31 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (turbosi03)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I think it's always true that the hotter the gas, the faster the velocity... this in turn spools the turbo faster
</TD></TR></TABLE>
The hotter the gas, the less viscous. This means that hotter gasses in a pipe experience less shear stress and thus less backpressure exists. THis however has nothing to do with average velocity across a cross section.
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
So again, it is not heat that spools a turbo. This is a very simple thermodynamics problem. You have one inlet, and one outlet. There are only two ways to extract energy from this simple system. Either decrease the velocity of the mass passing through the system (extract kinetic energy), or decrease the heat of the mass (extract entropy). Since a turbo is not designed as a heat exchanger, you must admit that the latter is very small in respect to the former.
It's mass flow rate.
</TD></TR></TABLE>
The hotter the gas, the less viscous. This means that hotter gasses in a pipe experience less shear stress and thus less backpressure exists. THis however has nothing to do with average velocity across a cross section.
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
So again, it is not heat that spools a turbo. This is a very simple thermodynamics problem. You have one inlet, and one outlet. There are only two ways to extract energy from this simple system. Either decrease the velocity of the mass passing through the system (extract kinetic energy), or decrease the heat of the mass (extract entropy). Since a turbo is not designed as a heat exchanger, you must admit that the latter is very small in respect to the former.
It's mass flow rate.
02-22-2005, 07:43 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (beepy)
I'll read that 20 or 30 more times. . . sleep on it, then post tomorrow.
Thank you for more deeply explaining to me what you already described to me in less detail in another thread. I honestly appreciate the sharing of knowledge.
Thank you for more deeply explaining to me what you already described to me in less detail in another thread. I honestly appreciate the sharing of knowledge.
02-22-2005, 09:15 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (beepy)
Isn't KE = 1/2mv^2?
Wouldn't this imply that the hotter (faster-moving) gas would provide more energy to spin the turbine? I'm assuming that if the gas cools as it makes its way though the manifold, that it would compress a bit, thus slowing down. In either case, the total mass of air moving past the compressor would be the same, but the hotter air would be travelling faster.
What's the relationship of heat and viscosity as it applies to spinning the turbine? Beepy notes that there's a loss of efficiency here, but how does that loss compare to the difference in KE?
Wouldn't this imply that the hotter (faster-moving) gas would provide more energy to spin the turbine? I'm assuming that if the gas cools as it makes its way though the manifold, that it would compress a bit, thus slowing down. In either case, the total mass of air moving past the compressor would be the same, but the hotter air would be travelling faster.
What's the relationship of heat and viscosity as it applies to spinning the turbine? Beepy notes that there's a loss of efficiency here, but how does that loss compare to the difference in KE?
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02-23-2005, 03:53 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (beepy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy »</TD></TR><TR><TD CLASS="quote">The hotter the gas, the less viscous. This means that hotter gasses in a pipe experience less shear stress and thus less backpressure exists. THis however has nothing to do with average velocity across a cross section.
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
So again, it is not heat that spools a turbo. This is a very simple thermodynamics problem. You have one inlet, and one outlet. There are only two ways to extract energy from this simple system. Either decrease the velocity of the mass passing through the system (extract kinetic energy), or decrease the heat of the mass (extract entropy). Since a turbo is not designed as a heat exchanger, you must admit that the latter is very small in respect to the former.
It's mass flow rate. </TD></TR></TABLE>
Wow, that sounded good, I'll go with it.
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
So again, it is not heat that spools a turbo. This is a very simple thermodynamics problem. You have one inlet, and one outlet. There are only two ways to extract energy from this simple system. Either decrease the velocity of the mass passing through the system (extract kinetic energy), or decrease the heat of the mass (extract entropy). Since a turbo is not designed as a heat exchanger, you must admit that the latter is very small in respect to the former.
It's mass flow rate. </TD></TR></TABLE>
Wow, that sounded good, I'll go with it.
02-23-2005, 05:46 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (rhettster)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rhettster »</TD></TR><TR><TD CLASS="quote">Isn't KE = 1/2mv^2?
Wouldn't this imply that the hotter (faster-moving) gas would provide more energy to spin the turbine? I'm assuming that if the gas cools as it makes its way though the manifold, that it would compress a bit, thus slowing down. In either case, the total mass of air moving past the compressor would be the same, but the hotter air would be travelling faster.
What's the relationship of heat and viscosity as it applies to spinning the turbine? Beepy notes that there's a loss of efficiency here, but how does that loss compare to the difference in KE?</TD></TR></TABLE>
This is how I have always looked at it.
. . . this may be a crappy example but here goes.
Hot air will always try to diffuse. If you have a bunch of HOT HOT HOT air inside a manifold, it is trying MUCH HARDER to escape from the manifold than cooler air would. If that statement is true - then I would still think that hotter air would help spool the turbo faster than cooler air.
I don't know that it would necessarily be enought to physically notice a difference - but every little edge helps, which is why I want to know the answer for sure. I'm still teedering on the fence on this one.
Wouldn't this imply that the hotter (faster-moving) gas would provide more energy to spin the turbine? I'm assuming that if the gas cools as it makes its way though the manifold, that it would compress a bit, thus slowing down. In either case, the total mass of air moving past the compressor would be the same, but the hotter air would be travelling faster.
What's the relationship of heat and viscosity as it applies to spinning the turbine? Beepy notes that there's a loss of efficiency here, but how does that loss compare to the difference in KE?</TD></TR></TABLE>
This is how I have always looked at it.
. . . this may be a crappy example but here goes.
Hot air will always try to diffuse. If you have a bunch of HOT HOT HOT air inside a manifold, it is trying MUCH HARDER to escape from the manifold than cooler air would. If that statement is true - then I would still think that hotter air would help spool the turbo faster than cooler air.
I don't know that it would necessarily be enought to physically notice a difference - but every little edge helps, which is why I want to know the answer for sure. I'm still teedering on the fence on this one.
02-23-2005, 06:00 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (beepy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy »</TD></TR><TR><TD CLASS="quote">
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
</TD></TR></TABLE>
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.
It cannot travel at a higher velocity unless the mass flow rate increased or the cross section of flow decreased. There is no arguing with the conservation of mass.
</TD></TR></TABLE>
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.
02-23-2005, 06:15 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (JonnyCoupe)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JonnyCoupe »</TD></TR><TR><TD CLASS="quote">
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.</TD></TR></TABLE>
This is exactly correct!! The equation for turbine power relies primarily on gas velocity (along with a few other things like angle of incidence, etc.). Pressure and heat are ways to store energy that can be used to increase gas velocity. Giving away this stored energy by allowing the heat to radiate from a long pipe will hurt the amount of work that can be done by the turbine.
That said, I've driven some of the rear mounted turbo cars and they work suprisingly well.
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.</TD></TR></TABLE>
This is exactly correct!! The equation for turbine power relies primarily on gas velocity (along with a few other things like angle of incidence, etc.). Pressure and heat are ways to store energy that can be used to increase gas velocity. Giving away this stored energy by allowing the heat to radiate from a long pipe will hurt the amount of work that can be done by the turbine.
That said, I've driven some of the rear mounted turbo cars and they work suprisingly well.
02-23-2005, 06:35 AM
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So I think most of us are in agreement that, Yes - hotter air will provide more energy for the turbine.
The way to consider this is that the turbine extracts heat energy from the gas, but it is the pressure of the gas that enables the turbine to do the extraction.
--------------- That makes me ask a totally different question that I will search on and make my own thread if need be. . . but for starters - -------------
With all of the above in mind - would Thermal "header" Wrap be more beneficial on the manifold (before the air hits the turbine) than say on the manifold and downpipe both?
Or would the manifold and downpipe being wrapped, keeping the air hot, provide an easier, or faster exit.
The way to consider this is that the turbine extracts heat energy from the gas, but it is the pressure of the gas that enables the turbine to do the extraction.
--------------- That makes me ask a totally different question that I will search on and make my own thread if need be. . . but for starters - -------------
With all of the above in mind - would Thermal "header" Wrap be more beneficial on the manifold (before the air hits the turbine) than say on the manifold and downpipe both?
Or would the manifold and downpipe being wrapped, keeping the air hot, provide an easier, or faster exit.
02-23-2005, 06:45 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (Beanbooger)
Good thread.
Ok. So, Heat is a form of radiating energy correct? So why did my turbo spool faster after I got tuned? I would imagine its from running more timing while maintaining safe fuel delivery and thus harnessing more power from I guess you could say more violently explosive combustion cycles. Which will also feed hotter gas into the manifold/turbo....
Why does your turbo spool faster when you use a nice turbo-thermal wrap? Its obviously trapping more heat in? Am I missing something?
Obviously mass flow has a lot to do with it. Its not like if you stick a turbo into an oven at 500deg. it will start spooling
. But I do believe that heat does play a good role in spooling the turbo from everything Ive ever read.
Ok. So, Heat is a form of radiating energy correct? So why did my turbo spool faster after I got tuned? I would imagine its from running more timing while maintaining safe fuel delivery and thus harnessing more power from I guess you could say more violently explosive combustion cycles. Which will also feed hotter gas into the manifold/turbo....
Why does your turbo spool faster when you use a nice turbo-thermal wrap? Its obviously trapping more heat in? Am I missing something?
Obviously mass flow has a lot to do with it. Its not like if you stick a turbo into an oven at 500deg. it will start spooling
. But I do believe that heat does play a good role in spooling the turbo from everything Ive ever read.
02-23-2005, 06:59 AM
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Re: (DragSource)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DragSource »</TD></TR><TR><TD CLASS="quote">
With all of the above in mind - would Thermal "header" Wrap be more beneficial on the manifold (before the air hits the turbine) than say on the manifold and downpipe both?
Or would the manifold and downpipe being wrapped, keeping the air hot, provide an easier, or faster exit.</TD></TR></TABLE>
For the most power and best spool characteristics you want the greatest pressure and temperature differentiation between the manifold and downpipe.
An ideal setup would be --
manifold -- thin-walled, tubular, ceramic coated, graduated collector, shortest equal length runners possible.
Turbine -- ball bearing(as long as we cannot choose VATN ) , ceramic coated housing
Downpipe -- Large as possible (4" if you can fit) , gradual curves, and made of a thermoconductive material like aluminum (This will not hold up under stressful heat cycling long however).
With all of the above in mind - would Thermal "header" Wrap be more beneficial on the manifold (before the air hits the turbine) than say on the manifold and downpipe both?
Or would the manifold and downpipe being wrapped, keeping the air hot, provide an easier, or faster exit.</TD></TR></TABLE>
For the most power and best spool characteristics you want the greatest pressure and temperature differentiation between the manifold and downpipe.
An ideal setup would be --
manifold -- thin-walled, tubular, ceramic coated, graduated collector, shortest equal length runners possible.
Turbine -- ball bearing(as long as we cannot choose VATN ) , ceramic coated housing
Downpipe -- Large as possible (4" if you can fit) , gradual curves, and made of a thermoconductive material like aluminum (This will not hold up under stressful heat cycling long however).
02-23-2005, 07:12 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (Boltz)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boltz »</TD></TR><TR><TD CLASS="quote">So why did my turbo spool faster after I got tuned? I would imagine its from running more timing while maintaining safe fuel delivery and thus harnessing more power from I guess you could say more violently explosive combustion cycles. Which will also feed hotter gas into the manifold/turbo....
</TD></TR></TABLE>
You spooled faster when you tuned because you ignition was set to make the best power possible. Not because of the heat....
</TD></TR></TABLE>
You spooled faster when you tuned because you ignition was set to make the best power possible. Not because of the heat....
02-23-2005, 08:20 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (adseguy)
yourself adseguy<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy »</TD></TR><TR><TD CLASS="quote">
You spooled faster when you tuned because you ignition was set to make the best power possible. Not because of the heat....
</TD></TR></TABLE>Maybe that wasnt the best example I could come up with, and what you stated is obvious. Just because it is making more power at the same boost level, doesnt neseccarily mean I have a larger mass flow rate, does it? obviously making more power when tuned, but I also noticed a big difference in how my turbo spooled (i.e. I recorded Certain RPM, with a certain load, what gear I was in, how long I was on it for, and the exact boost readout on my gauge) Not just seat of my pants dyno "spool time"
02-23-2005, 08:52 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (adseguy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy »</TD></TR><TR><TD CLASS="quote">
You spooled faster when you tuned because you ignition was set to make the best power possible. Not because of the heat.... </TD></TR></TABLE>
Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.
You spooled faster when you tuned because you ignition was set to make the best power possible. Not because of the heat....
</TD></TR></TABLE>Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.
02-23-2005, 09:02 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (tokes1320)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokes1320 »</TD></TR><TR><TD CLASS="quote">
Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.</TD></TR></TABLE>
There we go, someone that can make sense of what I type.
When I got tuned egt's went up with ignition timing. I also noticed that my turbo spooled faster, This shows me a direct correlation with heat and spool times.
Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.</TD></TR></TABLE>
There we go, someone that can make sense of what I type.
When I got tuned egt's went up with ignition timing. I also noticed that my turbo spooled faster, This shows me a direct correlation with heat and spool times.
02-23-2005, 09:05 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (Boltz)
And on that note, why do 2-steps/antilag work? Because they introduce fuel and much more heat/energy into the exhaust.
02-23-2005, 09:32 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (tokes1320)
People keep saying that heat is an important part of a turbo, then they say the rear mounted turbos work. I gave my thermodynamic explanation. I could go into fluid dynamics and explain that the kinetic energy stored in the moving gas can only change by the amount of head loss within the pipe (which is only related to heat slightly, since the viscosity of air does not change that much), but I don't think that would change people's minds, either.
Now... If you were to run a compressor off of a Sterling engine....
Now... If you were to run a compressor off of a Sterling engine....
02-23-2005, 11:47 AM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (beepy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy »</TD></TR><TR><TD CLASS="quote">People keep saying that heat is an important part of a turbo, then they say the rear mounted turbos work. I gave my thermodynamic explanation. I could go into fluid dynamics and explain that the kinetic energy stored in the moving gas can only change by the amount of head loss within the pipe (which is only related to heat slightly, since the viscosity of air does not change that much), but I don't think that would change people's minds, either.
Now... If you were to run a compressor off of a Sterling engine.... </TD></TR></TABLE>
Im not sure how much of your reply is based towards what I've said, but Ive been pretty open to suggestion because I dont want to believe what everyone does, I want to be able to understand the truth so I can help other people understand it if it ever comes up again.
Id be happy to read your fluid dynamics explanation
And whats all this about a sterling engine and a compressor?
Now... If you were to run a compressor off of a Sterling engine....
</TD></TR></TABLE>Im not sure how much of your reply is based towards what I've said, but Ive been pretty open to suggestion because I dont want to believe what everyone does, I want to be able to understand the truth so I can help other people understand it if it ever comes up again.
Id be happy to read your fluid dynamics explanation
And whats all this about a sterling engine and a compressor?
02-23-2005, 12:01 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (JonnyCoupe)
beepy, what about this guys statement?
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JonnyCoupe »</TD></TR><TR><TD CLASS="quote">
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JonnyCoupe »</TD></TR><TR><TD CLASS="quote">
Mass.... yes that doesnt change, but the density too, hence hotter will have a lower density and hence exhibit higher speeds as the mass flow rate remains the same the gas speed must increase to maintain it.</TD></TR></TABLE>
02-23-2005, 12:27 PM
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Re: Does HOTTER air BEFORE the turbine - cause faster spool (tokes1320)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokes1320 »</TD></TR><TR><TD CLASS="quote">
Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.</TD></TR></TABLE>
very true, but the benefits are minimal... As long as your not doing an 8 degree difference in timing the spool up isn't going to be anything more then a 100-200rpm. If you call that major then great! When I tune I usually see around 100-200 degrees of difference with more advance.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokes1320 »</TD></TR><TR><TD CLASS="quote">And on that note, why do 2-steps/antilag work? Because they introduce fuel and much more heat/energy into the exhaust.</TD></TR></TABLE>
Kinda....if you meant it like what i'm about to say fine....but otherwise you're kinda wrong.....Heat and energy yes, but the thing is 2step works by moving the timing so much so that the flame front travels into the manifold and the gasses expand in the manifold and turbo, therefore a turbo that is spooled up. The explosion doesn't happen entirly in the confines of the cylinder. This is way off topic though. so lets not argue about this.
Good info so far...especially beepys
Ignition timing is directly linked to EGT's.
*clap* *clap* *clap* *clap*
Heat = Energy, it only makes sense that the greater energy in your exhaust, the faster the turbo will spool.</TD></TR></TABLE>
very true, but the benefits are minimal... As long as your not doing an 8 degree difference in timing the spool up isn't going to be anything more then a 100-200rpm. If you call that major then great! When I tune I usually see around 100-200 degrees of difference with more advance.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokes1320 »</TD></TR><TR><TD CLASS="quote">And on that note, why do 2-steps/antilag work? Because they introduce fuel and much more heat/energy into the exhaust.</TD></TR></TABLE>
Kinda....if you meant it like what i'm about to say fine....but otherwise you're kinda wrong.....Heat and energy yes, but the thing is 2step works by moving the timing so much so that the flame front travels into the manifold and the gasses expand in the manifold and turbo, therefore a turbo that is spooled up. The explosion doesn't happen entirly in the confines of the cylinder. This is way off topic though. so lets not argue about this.
Good info so far...especially beepys
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bsmith100
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07-20-2010 10:31 AM
