my son has an 03 cobra and we got into a discussion with someone from sea level, He claims that his friend has ran at all different altitudes and since these cars are F/I he can run at any altitude within .10 of a second without any changes. Anyone actually go from sea level to any thing considered high 5000+ and anywhere in between without making anychanges (just letting the computer do it all) and stay within .10 sec?
Altitude
- Thread starter moparornocar2
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go to smokemup.com click on auto math and it will give you a correction factor for elevation.
I don't know about 1 tenth but F/I cars are not as affected as an N/A car...I lose a large percentage of power with large elevation changes where as an F/I car will lose a smaller percentage in equal conditions.
I would expect him to see a greater difference than a tenth but that's just me.
I would expect him to see a greater difference than a tenth but that's just me.
Your friend is full of crap. Just the weather changes here will affect et and mph more than a tenth. Just look at cars on this site that are in Colorado compared to cars closer to sea level. It is a huge difference. Not just tenths, we're talking full seconds.
FI will only keep the A/F ratio correct for changes in altitude, but thin air whether from high air temps or altitude will negatively affect power output. Even turbo'd aircraft run out of power at higher altitudes.
Fortunaly he is not our friend, I did use a correction factor and even asked the question in another thread, But when actually applying it, ( I went to the weather channel , got the track altitude, altimeter incheHg,track temp,dew point etc as asked by the calculator came up with the D/A and then did the corrected times , Then when presented those as a guidline , was told how stupid correction factors are and then told the story of the cobra running within .10. Shit at our local track we see temps change from 70degrees to 100+in one race day and wacth our times fall half a second in a F/I car? anymore feed back or examples would be great..F8LSNAKE said:
Did that and was told it was not relivant? Not for F/I cars.dohc32v said:
That's exactly what I'm talking about. I run high 10's in good fall air and low 11's in the heat. As far as my experience goes altitude and weather conditions affect all cars. FI computer controlled cars just adjust for it without having to do a jet change like on carbureted cars. In fact, they may even be affected moreso. A little nitrous oxide(atmosphere in a bottle) could fix it though.moparornocar2 said:
Altitude DOES AFFECT supercharged cars like it does N/A cars. If you dont believe me come to colorado and run your car. My cobra with all the mods(port, upper, lower, and all that crap) only puts out 410 ACTUAL RWHP here at altitude. Corrected (sealevel) numbers are 500rwhp. Now thats a BIG difference. My car has ran a best of 12.1 @ 115 here. About a full second slower than it would at sealevel. The avarage DA here at the track is 8000' So Come on out and check it out.
No thanks bro. It's a beautiful place, but I couldn't live anywhere my car would be that much slower than it already is. Your car is sweet btw.ZOSO said:
ZOSO said:
I did some math and looks like at sea level in not even ideal conditions you would be close to a 10.89-10.99.
ZOSO said:
Road trip:rockon:
DA around usually runs 4500-6000ft above sea level with the horrible air. I've talked to a guy that had a new C6 and claims to run 12.2-12.3s in Houston on street tires, comes here and runs 13.4x-13.6xs all night long. I would love to go to a track where conditions are a lot better as far as altitude goes.
Our DA is usually 8000 feet as well. We're atleast a full second behind sea level guys. FWIW, '06 Zo6's here run 13's on a good day. Completely stock '03cobras low 14's-maybe high 13's, stock lightning high 14's, stock Mach's low 15's-high 14's.
I know when I go to Vegas (about 2000 ft), I gain 3 lbs of boost. I'm only seeing 14-15 lbs here with my 2.8 upper, and 4 lb lower pulleys. If that gives you guys any idea of how altitude effects our cars.
Supercharged cars are as effected by altitude as n/a cars simply because of the change in boost pressure. When going from sea level to say 5000 feet, not only are you running in thinner air, your boost pressure drops a good amount too. Turbo cars aren't effected as much, but still are.
So whoever says they can run at any track and be within a tenth is straight up lying through his teeth.
I know when I go to Vegas (about 2000 ft), I gain 3 lbs of boost. I'm only seeing 14-15 lbs here with my 2.8 upper, and 4 lb lower pulleys. If that gives you guys any idea of how altitude effects our cars.
Supercharged cars are as effected by altitude as n/a cars simply because of the change in boost pressure. When going from sea level to say 5000 feet, not only are you running in thinner air, your boost pressure drops a good amount too. Turbo cars aren't effected as much, but still are.
So whoever says they can run at any track and be within a tenth is straight up lying through his teeth.
are D/A here im the summer .....hell even now..... is in the 3900-5200s and are track elevation is 2350ft so it suck when you are trying to run a fast time here i can go 300 or so miles to KC where its 750ft
moparornocar2 said:
Maryland International Raceway in the 100 degree heat (2400 DA) I was running 11.30s... went to Bristol, TN in the 90+ degree heat (5500 DA) and my quicker passes all out if I wouldn't have been on the brakes (bracket racing) would have been 11.70s... I was down just a bit on my 60 foots so I would say the difference I noticed from the two tracks mentioned and the difference in DA would have been a good 3 tenths.
Me personally, when someone says FI doesn't do much could be considered by... one, effecieincy of a turbo and how much boost it delivers, even at higher altitudes... two, rotor/ts/cent blowers push boost which cause heat on top of the heat already coming in from the temps and bad air due to DA. IMHO, Turbo car wouldn't be hurt much as the other FI (no N2O involved) cars would be.
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amen JR it seems that the only people that understand da and how much it changes your et live where the altitude is over 3000' , I talk to people from albuquerque about a 14 second pass in my 2004 gt and they say thats a good run , but if you talk to someone from mustang world from florida he will say that you cant drive and his bone stock 96gt runs 14 flat all day at a track 3 feet from the sea...
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