Altitude Correction
6th Gear Member
Joined: Sep 2006
Posts: 5,565
From: NC
6th Gear Member
Joined: Apr 2007
Posts: 10,468
From: California
Talk about a topic that's been bludgeoned to death...
The biggest point of the DA correction is comparison. When you have 2 cars running at 2 tracks in 2 different conditions in 2 different parts of the country at 2 different times, there's NO WAY you could have any type of a remotely valid comparison without eliminating some of the variables. The DA correction helps to eliminate those variables(primarily weather and altitude) and then mainly leaves driving and track prep as variables. It allows for a more valid comparison between the performance of 2 vehicles but is still only a ballpark figure.
Even then the variable you can NOT eliminate(not without testing it and coming up with another calculation, which would be specific to each vehicle) is how each car would handle increased power as it relates to traction. You could theoretically have 1 car "correct" to a faster ET/MPH but react worse in terms of suspension, and the slower "corrected" car may in reality be faster in terms of real world ET.
The biggest point of the DA correction is comparison. When you have 2 cars running at 2 tracks in 2 different conditions in 2 different parts of the country at 2 different times, there's NO WAY you could have any type of a remotely valid comparison without eliminating some of the variables. The DA correction helps to eliminate those variables(primarily weather and altitude) and then mainly leaves driving and track prep as variables. It allows for a more valid comparison between the performance of 2 vehicles but is still only a ballpark figure.
Even then the variable you can NOT eliminate(not without testing it and coming up with another calculation, which would be specific to each vehicle) is how each car would handle increased power as it relates to traction. You could theoretically have 1 car "correct" to a faster ET/MPH but react worse in terms of suspension, and the slower "corrected" car may in reality be faster in terms of real world ET.
Pro. B.S. caller outer
Joined: May 2004
Posts: 9,644
From: IL
lol are some of you guys sharing the same bong or what?? 
I think the point here is being missed. The NHRA themselves told me that the altitude corrected time, from an appropriate track such as mine, counts for records. So I'm sorry AZ I'm going to have to go with the NHRA on this one brah.
The point of these correction factors is to give you the time that you would have run if your track had been at sea level. All else being equal. These corrections are good enough for them to take seriously so they should be good enough for you too. Unless you think you're more of an authority on the subject than they are?
Ofcourse track prep for instance could be different if I ran at a DIFFERENT track that same day at sea level. That is completely beside the point.
I don't think Mishri or I or anyone else on here has ever to my knowledge done a corrected time and presented it as an actual. But it is a bit tiresome to hear the naysayers pop in and get after you for simply quoting a corrected time in context.
I think the point here is being missed. The NHRA themselves told me that the altitude corrected time, from an appropriate track such as mine, counts for records. So I'm sorry AZ I'm going to have to go with the NHRA on this one brah.
The point of these correction factors is to give you the time that you would have run if your track had been at sea level. All else being equal. These corrections are good enough for them to take seriously so they should be good enough for you too. Unless you think you're more of an authority on the subject than they are?
Ofcourse track prep for instance could be different if I ran at a DIFFERENT track that same day at sea level. That is completely beside the point.
I don't think Mishri or I or anyone else on here has ever to my knowledge done a corrected time and presented it as an actual. But it is a bit tiresome to hear the naysayers pop in and get after you for simply quoting a corrected time in context.
2010 Blue Ball Award Recipient
Joined: Dec 2004
Posts: 7,907
From: Eskimo Village, Indiana *No Igloo*
Does anyone know how to do it backwards?
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
5th Gear Member
Joined: Mar 2006
Posts: 2,955
From: ATL
Does anyone know how to do it backwards?
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
6th Gear Member
Joined: Oct 2003
Posts: 8,635
From: North Cackilacky
That's simply not true. At the lower altitude you are obviously putting down more power. Who's to say you would get the same traction as you did with the reduced power??
Also, based on this logic, why even run races. You could just look at engine configuration and altitude and then bust out the calculators and figure out the winner without even cranking the engine.
Also, based on this logic, why even run races. You could just look at engine configuration and altitude and then bust out the calculators and figure out the winner without even cranking the engine.
5th Gear Member
Joined: Jul 2007
Posts: 3,731
the problem is it's not what 'WOULD' have happened, it's what 'COULD' have happened. It's saying that all things being the best they can possibly be, that's what your car is capable of in a "best possible run" scenario.
you can't claim "what could be" as "what is"
you can't claim "what could be" as "what is"
5th Gear Member
Joined: Mar 2007
Posts: 2,031
From: Orlando, FL
Its all about the 60' time, like grandpastang and chain1 said. Especially when running on street tires when its really hit or miss. I wonder how the correction affects 60' time (does it lower that?).
Example: Say you are running on street tires making 250 hp at high alt, and pull a 1.90 60' time. At a sea level correction you are making 350+ hp, does the correction bring down your 60' time to 1.6-1.7 or something (highly unlikely joe smoe is pulling that 60' on street tires)? The correction factor does not know the capabilities of the tires (or the driver).
I guess it would be helpful to know the correction factor formula and how it effects everything (maybe the website shows it, I didnt check).
I think this is where everyone gets a little untrusting of corrected times.
Like JD said, intelligent people will understand that you are running in some crap conditions.
Example: Say you are running on street tires making 250 hp at high alt, and pull a 1.90 60' time. At a sea level correction you are making 350+ hp, does the correction bring down your 60' time to 1.6-1.7 or something (highly unlikely joe smoe is pulling that 60' on street tires)? The correction factor does not know the capabilities of the tires (or the driver).
I guess it would be helpful to know the correction factor formula and how it effects everything (maybe the website shows it, I didnt check).
I think this is where everyone gets a little untrusting of corrected times.
Like JD said, intelligent people will understand that you are running in some crap conditions.
6th Gear Member
Joined: Sep 2006
Posts: 5,565
From: NC
Does anyone know how to do it backwards?
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
I did not click the link so I'm not sure how specific the table gets, but if I ran a 13.6@100 with XXX DA *good like it was that night*, could I then convert it to say, a time up in the mountians?
If so, I'll run around with a DA Uncorrected ET in my signature to make people feel better.
It takes some time (like figuring out crank HP when you know the DTL % and rwhp of a car)...just crank the numbers by hand until you match.
