The problem is see, is that he'll make a huge number, but then go out and run slower than warmed over vp truck. Whereas the said Midwest trucks will put up a huge number, then go run really fast. It's that that's the only thing he can do, most everyone else is either a racer or puller who happens to strap it onto the dyno, he's just been a dyno douche.
And don't come back with "it's just too much power, it breaks every time", then he needs to pull his head out of his a$$, back the power off a little to get the truck running consistently, then tweak the tune adding power, you know like every other successful team does.
Sent from my SAMSUNG-SM-G930A using Tapatalk
I'm not saying he wouldn't have still won, but why even use a correction factor other than it gives him the ability to bolster a "record" that wasn't really ever achieved. These correction factors are starting to remind me of entitlement benefits...."Its not fair that location has thicker air, we need to make it equal everywhere and give us pitty points on the dyno so we can have what they have at lower elevations"...lol.
But that's the point, applying an n/a correction is exactly as inaccurate as no correction.I used to be a big "Hater" of corrected dyno numbers, but there is one important lesson I've learned after owning and operating a dyno at high altitude that lessens my "hate" of correction factors:
Turbo-Charged vehicles, be it gas or diesel, with a properly "conservatively" sized turbo setup, like an OEM application at OEM boost/power levels do seem to make roughly the same raw HP numbers here as they do at sea level, within 0 to 5% on most setups despite the weather station/density altitude calling for 17% to 20% here at 5700'.
The engineering explanation on Borg's site seems to be the general consensus: the turbo is able to spin faster at high altitude due to thinner air and is able to almost entirely create the same mass flow of air into the engine and therefore power numbers are very similar. Turbo maps demonstrate that compressor efficiency declines as pressure ratio increases and pressure ratio does increase as you go up in altitude/lower turbo inlet pressure. On an OEM application, they generally run right in the middle of the compressor map and so the increased compressor RPM does not create a significant efficiency loss.
On a maximum effort truck, pushing turbos to the limits of their compressor maps, or pushing the compressor flow to the maximum available, the higher speed compressor does experience a significant efficiency and mass flow decline with lower inlet pressure/higher pressure ratio across the compressor.
Case in point: My Junker Drag Truck that is airflow limited 60mm over 83mm picks up significant power going down in elevation because it runs at the limit of its "undersized" turbo setup. Back when the truck was "fuel-limited" and would clean up down at lower altitude, it experienced almost zero power loss between 2000' Vegas and 4600' Utah.
My 98' 12V daily driver with a 63/S480 turbo setup pushing 585 uncorrected HP or 685 corrected HP picks up very very little down at sea level, maybe 3% or so for a legitimate 600 uncorrected HP. Spool increases, torque #increase, but peak power is roughly the same because the big 120 lb/min S480 running at a 3:1 to 3.5:1 pressure ratio is right in the middle of the compressor flow map and the extra RPM/pressure ratio does not create a significant efficiency loss at altitude.
If you'd like to see another real-world article, read up on the test Truck Trend or Diesel Power Mag did a few years back when the new 400HP Ford 6.7 came out. They pitted it against the 397HP Dmax and 285HP Cummins on a max effort tow test through Eisenhower Tunnel at 10k elevation. The Ford came-in dead last despite the highest factory "sea level" HP numbers. Now it is possible that the Dmax was conservative on their power rating, or that the Cummins had perfect gearing (I tease), but not 25% conservative or whatever the final results were. Later, I assume due to Ford's embarrassment, another towing test was held down near the low altitude Colorado river in Arizona and the Ford came to life. The biggest difference was the factory Dmax had "reserve" capacity in the factory turbo and the Ford sequential turbo was maxed out at sea level. Ford has since fixed the problem with a turbo upgrade, but the truth of the matter, ELEVATION DOES MATTER, how much depends on the individual truck combination.
From our in-house testing, racing at various elevations, etc. we have come up with legitimate correction factors that translate to the real world, but they are still truck combo/turbo setup dependent. The Junker picks up 5% going down in altitude from 5700' to 2800', boost pressure goes up a bit as well. Next weekend in Texas at the World Finals, hopefully we'll get enough data to make some HP conclusions between 5700' and 80' or whatever the altitude is there in Ennis.
As far as dynos, the guy's truck obviously makes a ton of power. But any "World Record" attempt should be done at low altitude where's it an actual number, instead of some theoretical calculation. Also, using a CF with Nitrous, that's a joke right?
I used to be a big "Hater" of corrected dyno numbers, but there is one important lesson I've learned after owning and operating a dyno at high altitude that lessens my "hate" of correction factors:
Turbo-Charged vehicles, be it gas or diesel, with a properly "conservatively" sized turbo setup, like an OEM application at OEM boost/power levels do seem to make roughly the same raw HP numbers here as they do at sea level, within 0 to 5% on most setups despite the weather station/density altitude calling for 17% to 20% here at 5700'.
The engineering explanation on Borg's site seems to be the general consensus: the turbo is able to spin faster at high altitude due to thinner air and is able to almost entirely create the same mass flow of air into the engine and therefore power numbers are very similar. Turbo maps demonstrate that compressor efficiency declines as pressure ratio increases and pressure ratio does increase as you go up in altitude/lower turbo inlet pressure. On an OEM application, they generally run right in the middle of the compressor map and so the increased compressor RPM does not create a significant efficiency loss.
On a maximum effort truck, pushing turbos to the limits of their compressor maps, or pushing the compressor flow to the maximum available, the higher speed compressor does experience a significant efficiency and mass flow decline with lower inlet pressure/higher pressure ratio across the compressor.
Case in point: My Junker Drag Truck that is airflow limited 60mm over 83mm picks up significant power going down in elevation because it runs at the limit of its "undersized" turbo setup. Back when the truck was "fuel-limited" and would clean up down at lower altitude, it experienced almost zero power loss between 2000' Vegas and 4600' Utah.
My 98' 12V daily driver with a 63/S480 turbo setup pushing 585 uncorrected HP or 685 corrected HP picks up very very little down at sea level, maybe 3% or so for a legitimate 600 uncorrected HP. Spool increases, torque #increase, but peak power is roughly the same because the big 120 lb/min S480 running at a 3:1 to 3.5:1 pressure ratio is right in the middle of the compressor flow map and the extra RPM/pressure ratio does not create a significant efficiency loss at altitude.
If you'd like to see another real-world article, read up on the test Truck Trend or Diesel Power Mag did a few years back when the new 400HP Ford 6.7 came out. They pitted it against the 397HP Dmax and 285HP Cummins on a max effort tow test through Eisenhower Tunnel at 10k elevation. The Ford came-in dead last despite the highest factory "sea level" HP numbers. Now it is possible that the Dmax was conservative on their power rating, or that the Cummins had perfect gearing (I tease), but not 25% conservative or whatever the final results were. Later, I assume due to Ford's embarrassment, another towing test was held down near the low altitude Colorado river in Arizona and the Ford came to life. The biggest difference was the factory Dmax had "reserve" capacity in the factory turbo and the Ford sequential turbo was maxed out at sea level. Ford has since fixed the problem with a turbo upgrade, but the truth of the matter, ELEVATION DOES MATTER, how much depends on the individual truck combination.
From our in-house testing, racing at various elevations, etc. we have come up with legitimate correction factors that translate to the real world, but they are still truck combo/turbo setup dependent. The Junker picks up 5% going down in altitude from 5700' to 2800', boost pressure goes up a bit as well. Next weekend in Texas at the World Finals, hopefully we'll get enough data to make some HP conclusions between 5700' and 80' or whatever the altitude is there in Ennis.