does altitude affect times with a turbo inducted car?
11-26-2004, 03:41 PM
#1
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does altitude affect times with a turbo inducted car? I say no because the air that goes in the engine is compressed, and therefore there will be no diffrence between a car boosting 5psi at sea lvl, and a car boosting 5psi at 10K feet...
I got it from here...
someone said
(turbo v6 owner)
then i said
so he says
so whatcya think? does alt. really affect times ifu have a FI (actually turbo) setup?
I got it from here...
someone said
Uh, actually that isn't good. At 8000ft. i was trapping 77.41 in the 1/8th mile. Only trapping 78 at sea level isn't impressive at all.
then i said
FYI, alt. doesnt matter with turbo cars... you are running off of compressed air... doesnt matter if you are at sea lvl, or at 10K feet, u will still see the same boost...
so this means ur 77 is actually slower compared to this 78....
so this means ur 77 is actually slower compared to this 78....
It's amazing how you and Tiago came in here and displayed your overwhelming ignorance regarding altitude and Turbos. Read what i posted on page 1, retard. Altitude matters to EVERYTHING... Be it a Turbo car, or a turbojet engine.... altitude affects every single engine in the entire world that requires air and fuel to make power. It doesn't matter if it's forced induction or not, it loses power with altitude.
You all are some of the most ignorant people i've ever come across. If you've never raced a car in CO or elsewhere in higher elevation, BE QUIET. I would love to see you and Tiago come up here and see EXACTLY what happens in ambient air pressure of 11psi.
EDIT:
Here, i copied and pasted it for you, Camaroseal, since you were too stupid to find it the first time before posting:
Thats wrong Tiago, the difference can be seen in absolute manifold pressure, which is Ambient + boost. Lets say i want to run 22psi of absolute pressure. At sea level, 14.7psi + 7.3psi boost = 22psi AMP. At my elevation 11psi + 11psi = 22psi AMP. So right there, your respected FI source is wrong, because it doesn't matter where the boost is coming from (Turbo, or SC), the power loss is still there.
Your source sounds like he's never tuned a car at elevation either.
"Optimum mix with “later” ignition can produce more power because more energy is released from the combustion of gasoline. Here’s why: When hydrocarbons like gasoline combust, the burn process actually happens in multiple stages. First the gasoline molecules are broken up into hydrogen and carbon. The hydrogen combines with oxygen from the air to form H2O (water) and the carbon molecules form CO. This process happens very fast at the front edge of the flame front. The second stage converts CO to CO2. This process is relatively slow and requires water molecules (from the first stage) for completion. If there is no more oxygen available (most of it consumed in the first stage), the second stage can't happen. But about 2/3 of the energy released from the burning of the carbon is released in the second stage. Therefore a richer mixture releases less energy, lowering peak pressures and temperatures, and produces less power. A secondary side effect is of course also a lowering of knock probability. It's like closing the throttle a little. A typical engine does not knock when running on part throttle because less energy and therefore lower pressures and temperatures are in the cylinder."
The above comes from Innovate Motorsports, a tuning company who does alot of tuning at altitude.
So, in case you didn't understand what i posted (which i assume you didn't), what it's saying is yes, the molecule content is there, but the oxygen content is not. Less oxygen content means the second stage of the burning process (where 2/3 of the power is released) has difficulty occuring.
So, if turbo cars aren't affected by elevation, go ahead and bring one of your piece of **** kits up here to Bandimere Speedway, actual elevation 5800ft, average DA 7000-9000ft and see what happens.
The reason a S/C car sees more of a loss, like an N/A car, is because the motor itself has less power to spin the pulley.
Nitrous is the only power adder that knows no altitude, because the N20 itself has the oxygen content needed to make power, regardless of elevation. But, the power the motor is making is still less than that of sea level, so that's why even nitrous cars still run slower times up here.
You all are some of the most ignorant people i've ever come across. If you've never raced a car in CO or elsewhere in higher elevation, BE QUIET. I would love to see you and Tiago come up here and see EXACTLY what happens in ambient air pressure of 11psi.
EDIT:
Here, i copied and pasted it for you, Camaroseal, since you were too stupid to find it the first time before posting:
Thats wrong Tiago, the difference can be seen in absolute manifold pressure, which is Ambient + boost. Lets say i want to run 22psi of absolute pressure. At sea level, 14.7psi + 7.3psi boost = 22psi AMP. At my elevation 11psi + 11psi = 22psi AMP. So right there, your respected FI source is wrong, because it doesn't matter where the boost is coming from (Turbo, or SC), the power loss is still there.
Your source sounds like he's never tuned a car at elevation either.
"Optimum mix with “later” ignition can produce more power because more energy is released from the combustion of gasoline. Here’s why: When hydrocarbons like gasoline combust, the burn process actually happens in multiple stages. First the gasoline molecules are broken up into hydrogen and carbon. The hydrogen combines with oxygen from the air to form H2O (water) and the carbon molecules form CO. This process happens very fast at the front edge of the flame front. The second stage converts CO to CO2. This process is relatively slow and requires water molecules (from the first stage) for completion. If there is no more oxygen available (most of it consumed in the first stage), the second stage can't happen. But about 2/3 of the energy released from the burning of the carbon is released in the second stage. Therefore a richer mixture releases less energy, lowering peak pressures and temperatures, and produces less power. A secondary side effect is of course also a lowering of knock probability. It's like closing the throttle a little. A typical engine does not knock when running on part throttle because less energy and therefore lower pressures and temperatures are in the cylinder."
The above comes from Innovate Motorsports, a tuning company who does alot of tuning at altitude.
So, in case you didn't understand what i posted (which i assume you didn't), what it's saying is yes, the molecule content is there, but the oxygen content is not. Less oxygen content means the second stage of the burning process (where 2/3 of the power is released) has difficulty occuring.
So, if turbo cars aren't affected by elevation, go ahead and bring one of your piece of **** kits up here to Bandimere Speedway, actual elevation 5800ft, average DA 7000-9000ft and see what happens.
The reason a S/C car sees more of a loss, like an N/A car, is because the motor itself has less power to spin the pulley.
Nitrous is the only power adder that knows no altitude, because the N20 itself has the oxygen content needed to make power, regardless of elevation. But, the power the motor is making is still less than that of sea level, so that's why even nitrous cars still run slower times up here.
11-26-2004, 04:36 PM
#2
You have obviously never driven your vehicle over any mountains. You would be amazed at the difference in power with an elevation change of only a couple of hundred feet. At 5 or 6 thousand feet, your powerful hot rod is transformed into a slug you would be embarassed to drive to the strip if it ran like that at sea level. BTW, this applies to forced induction as well as NA. Turbos are not affected by the same percentage of loss, however, because they do not spin at a fixed rpm relative to engine speed. This allows them to partially compensate for the less dense air because they will spin faster, compressing the air better. In the end, you still lose power as altitude increases, even with a good turbo setup.
11-26-2004, 04:45 PM
#3
Yep sorry to say it does. The lower the altitude the DENSER the air is(more oxygen) With boosted engines up here, you will boost whatever psi, but the air is LESS DENSE(less oxygen) up at altitude. Less oxygen less horsepower. With a turbo powered car it won't matter all that much because you can increase the boost by turning a **** but thats besides the point. I'm supercharged, and we have two tracks here in New Mexico. With my ol powerdyne set up I was turning 12.5s@109 on 6psi consistently at our track in Albuquerque(5600ft+ not factoring in DA) with decent 1.75-1.80 60fts. I then made a trip down to Roswell NM which is at 3800ft, EXACT same set up no changes not even in the tune, the car went 12.1@117mph with a worse 1.90-1.95 60fts, the car was now seeing 8psi at the traps.
Yeah you can compress air all you want, but its density matters, you guys at sea level have nice dense air, us high altitude guys have less dense air compressed or uncompressed.
Our turbo mustang guys consistently go .5 to 1 sec slower up here then when they compete in Las Vegas or in Arizona FWIW.
And N2O is N2O its adding its own oxygen to the combustion process so if you run 12's on N2O at sea level you will run 12's up here too,
J
Yeah you can compress air all you want, but its density matters, you guys at sea level have nice dense air, us high altitude guys have less dense air compressed or uncompressed.
Our turbo mustang guys consistently go .5 to 1 sec slower up here then when they compete in Las Vegas or in Arizona FWIW.
And N2O is N2O its adding its own oxygen to the combustion process so if you run 12's on N2O at sea level you will run 12's up here too,
J
11-26-2004, 04:46 PM
#4
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there are no mountains in FL 
but see, the turbine will spin and spin until there is enough boost to push that wastegate valve open... now maybe if u didnt have a wastegate, and u just let the turbo spool and spool, u might see 9psi instead of 10-11 but mostly we all have wastegates...
amd i even understanding what ure saying?
but see, the turbine will spin and spin until there is enough boost to push that wastegate valve open... now maybe if u didnt have a wastegate, and u just let the turbo spool and spool, u might see 9psi instead of 10-11 but mostly we all have wastegates...
amd i even understanding what ure saying?
11-26-2004, 04:48 PM
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Originally Posted by frcefed98
Yep sorry to say it does. The lower the altitude the DENSER the air is(more oxygen) With boosted engines up here, you will boost whatever psi, but the air is LESS DENSE(less oxygen) up at altitude. Less oxygen less horsepower. With a turbo powered car it won't matter all that much because you can increase the boost by turning a **** but thats besides the point. I'm supercharged, and we have two tracks here in New Mexico. With my ol powerdyne set up I was turning 12.5s@109 on 6psi consistently at our track in Albuquerque(5600ft+ not factoring in DA) with decent 1.75-1.80 60fts. I then made a trip down to Roswell NM which is at 3800ft, EXACT same set up no changes not even in the tune, the car went 12.1@117mph with a worse 1.90-1.95 60fts, the car was now seeing 8psi at the traps.
Yeah you can compress air all you want, but its density matters, you guys at sea level have nice dense air, us high altitude guys have less dense air compressed or uncompressed.
Our turbo mustang guys consistently go .5 to 1 sec slower up here then when they compete in Las Vegas or in Arizona FWIW.
And N2O is N2O its adding its own oxygen to the combustion process so if you run 12's on N2O at sea level you will run 12's up here too,
J
Yeah you can compress air all you want, but its density matters, you guys at sea level have nice dense air, us high altitude guys have less dense air compressed or uncompressed.
Our turbo mustang guys consistently go .5 to 1 sec slower up here then when they compete in Las Vegas or in Arizona FWIW.
And N2O is N2O its adding its own oxygen to the combustion process so if you run 12's on N2O at sea level you will run 12's up here too,
J
confusing stuff eh
11-26-2004, 04:51 PM
#6
Good response gametech. My car definately loses whatever ***** it has when I drive up to work(found out its 9500ft above sea level)
have to drive through and up a mountain pass to get to work.
Makes me glad to be racing at a average DA of @7000FT here in albuquerque.
have to drive through and up a mountain pass to get to work.Makes me glad to be racing at a average DA of @7000FT here in albuquerque.
11-26-2004, 04:55 PM
#7
Originally Posted by seal
I see now.... hmmm
confusing stuff eh
confusing stuff eh
J
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11-26-2004, 05:02 PM
#8
The biggest issue w/ the turbo car at altitude is not the loose of boost persay, it's the heat. Assuming the turbo can flow enough air to maintain the pressure, the wastegate will regulate the manifold pressure to an absolute pressure within reason. The big problem is you're asking the turbo to operate at a larger pressure ratio since your inlet pressure is lower due to the altitude.
You might not lose power from the loss of boost, but the added heat and somewhat less dense intake charge will kill power.
The biggest thing to watch though is the cooling capacity at altitude. W/ the less dense ambient air, the cooling system capacity to remove heat drops right along with the baro.
I'm routinely on altitude trips for work to Denver, and up into the mountains, pikes peak, etc etc. Altitude sucks
Even my oxygen intake is too low, i'm light headed the whole time i'm out there
I'll take sea level any day
You might not lose power from the loss of boost, but the added heat and somewhat less dense intake charge will kill power.
The biggest thing to watch though is the cooling capacity at altitude. W/ the less dense ambient air, the cooling system capacity to remove heat drops right along with the baro.
I'm routinely on altitude trips for work to Denver, and up into the mountains, pikes peak, etc etc. Altitude sucks
Even my oxygen intake is too low, i'm light headed the whole time i'm out there
I'll take sea level any day
11-26-2004, 05:10 PM
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As it was mentioned before, every car will lose power at atltitude. N/A cars just tend to lose more power than a boosted car. For example...I run mid 14s at 5k feet while the srt4 will run low 14s up here. Altitude sucks. To believe...the srt4 will actually beat me. 
11-26-2004, 05:19 PM
#11
yep SRT-4s are to be respected around here in ALB, NM if you have a stock LS1 f-body. Those lil buggers are going 14.0s-13.8s stock up here depending on the driver.
Stock LS1 f bodies go 14.7-14.5s
Don't even want to mention the LT1 gang.
We have more fast SRT-4's than LS1 f-bodies here which is very embarrassing for the LS1 camp.
Glad I don't have to worry about that.
J
Stock LS1 f bodies go 14.7-14.5s
Don't even want to mention the LT1 gang.We have more fast SRT-4's than LS1 f-bodies here which is very embarrassing for the LS1 camp.
Glad I don't have to worry about that.
J
11-26-2004, 06:00 PM
#12
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Originally Posted by frcefed98
yep SRT-4s are to be respected around here in ALB, NM if you have a stock LS1 f-body. Those lil buggers are going 14.0s-13.8s stock up here depending on the driver.
Stock LS1 f bodies go 14.7-14.5s Don't even want to mention the LT1 gang.
We have more fast SRT-4's than LS1 f-bodies here which is very embarrassing for the LS1 camp.
Glad I don't have to worry about that.
J
Stock LS1 f bodies go 14.7-14.5s
Don't even want to mention the LT1 gang.We have more fast SRT-4's than LS1 f-bodies here which is very embarrassing for the LS1 camp.
Glad I don't have to worry about that.
J
And yes...i agree. Its very embarrassing when someone in a neon says they can smoke me...and they CAN! 
11-27-2004, 12:26 AM
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Are you guys sure these neons are stock? I used to live in Reno (4500') and race at a track at 5000' (not sure what the DA was but track temps easily over 100) and I never had a problem with them. My car ran high 13's at 103 (stock) and they were mid to high 14's. Just curious.
11-27-2004, 12:43 AM
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Originally Posted by BOOSTAT4500
Are you guys sure these neons are stock? I used to live in Reno (4500') and race at a track at 5000' (not sure what the DA was but track temps easily over 100) and I never had a problem with them. My car ran high 13's at 103 (stock) and they were mid to high 14's. Just curious.
100% positive. I have two friends that have srt4's (stock). The ones that are slightly modded are pulling 13.5's or so. Its quite a sad story up here.
11-27-2004, 09:30 AM
#15
To compensate for higher altitudes Top Fuel teams use to raise the compression ratio's and speed the blowers up (blowers don't last as long, and they throw belts easier)with smaller pulleys.
With the new 85% nitro rule in effect I'm not sure how they are going to deal with the higher altitudes. One of the things they have done with the new 85% rule was speed the blowers up to compensate for the 5% loss of nitro. Now they have trouble with blowers not lasting from spinning them so fast.
So I'm not sure how they will deal with the higer altitudes next year because they are spinning them at max rpm at the lower altitudes, but I'm sure they will figure it out, they always do. I'm guessing somebody will come up with a better supercharger that will with stand the higher rpms that they want to spin them.
TJ
With the new 85% nitro rule in effect I'm not sure how they are going to deal with the higher altitudes. One of the things they have done with the new 85% rule was speed the blowers up to compensate for the 5% loss of nitro. Now they have trouble with blowers not lasting from spinning them so fast.
So I'm not sure how they will deal with the higer altitudes next year because they are spinning them at max rpm at the lower altitudes, but I'm sure they will figure it out, they always do. I'm guessing somebody will come up with a better supercharger that will with stand the higher rpms that they want to spin them.
TJ
11-27-2004, 12:36 PM
#17
if my mechanical boost gauge reads 0 sitting in my hand here around sea level, what does it read in denver? I assume that all boost gauges are calibrated to be at 0 at sea level. is this wrong?
if it is right..
a)your wastegate if referenced mechanically (bleeder/regulator) will increase boost to xpsi above the pressure of your location.
b)your wastegate if actuated electrically (electric boost controller) will increase boost until x psi over sea level
a)people will make less horsepower than b) people
if it is right..
a)your wastegate if referenced mechanically (bleeder/regulator) will increase boost to xpsi above the pressure of your location.
b)your wastegate if actuated electrically (electric boost controller) will increase boost until x psi over sea level
a)people will make less horsepower than b) people
11-27-2004, 09:03 PM
#19
Originally Posted by ~RedLineLs1~
As it was mentioned before, every car will lose power at atltitude. N/A cars just tend to lose more power than a boosted car. For example...I run mid 14s at 5k feet while the srt4 will run low 14s up here. Altitude sucks. To believe...the srt4 will actually beat me.
damn.
hope i can pull a 14 here............
so when's bandamiere open?
i cant wait to see this altitude ruin my power here (sigh)
<---------moved to colorado from chicago
11-27-2004, 09:18 PM
#20
Originally Posted by MIGHTYMOUSE
if my mechanical boost gauge reads 0 sitting in my hand here around sea level, what does it read in denver? I assume that all boost gauges are calibrated to be at 0 at sea level. is this wrong?
If the gauge works like i think it does, you'd actually read 9 to 13 in hg vac.
Even notice bags of chips are all puffed up in Denver? at least the ones packaged at sea level