2005 LGT 1/4 mile track results....

[Driver72]

Okay, so I met up with my buddy who has a new 05 LGT sedan Limited 5MT at Los Angeles Country Raceway (LACR) for him to do his first runs in the car. He had 1200+ miles on the car...completely stock. Conditions at LACR were horrible. It was 82 degrees at 7:30 pm but there was a 20-30 mph nearly head on wind. If you were going down the track the wind was hitting your car at the right front quarter panel. So it was basically a 3/4 front wind. This track runs VERY slow, so take these times with a grain of salt. I recorded times from other cars. Many of whom I spoke to to find out if they were stock or modded. My friend traded in his 2003 EVO for the 05 LGT. He has been at this track many times, and apparently it's usually at least partially windy like this. His best times in his EVO when stock was a 14.4 His best time last night was: 60 foot 2.02 1/4 in 15.1 @ 89 mph But let me say this too, he tried to hold 3rd gear through the run, but the car hit the rev limiter before it hit the stripe. Actually he said it hit it and backed off, then hit it again, then he crossed. So, I'm sure he would of been in the 14's and probably 91+ mph if he'd of shifted. He also said he was afraid to launch at higher than 4K rpms. He said he was probably in the 3500-4000K range. He also knew he got a bad launch. His first run he blew REALLY bad and had a 2.28 60 ft time and a 16.1 His secod run he also blew with I think a 2.19 and a 15.4 @ 89 mph But for comparison sake here's the best times of some other cars that were there: 2005 WRX STi (stock) brand new no plates yet: 14.6 @ 93 2004 EVO (stock) brand new no plates yet. This guy had trouble launching, a Scion jumped him a 1/2 car off the line. He got: 15.4 @ 93 2003 GTI 1.8T manual (stock): 16.2 2003 RSX-S (stock): 16.3 G35 Coupe 6MT (19" wheels): 15.7 @ 92 G35 Sedan (auto) 19" wheels with intake only: 15.8 @ 89 2003 Corvette Z06 (stock): 13.2 @ 109 mph C5 Corvette manual (stock) He had a bad launch: 15.1 @ 98 Chrysler 300....yeah it had a HEMI...brand new, stock: 15.2 @ 91 2003 Mustang SVT Cobra: 13.9 @ 104 2002 Nissan Altima SE (manual) stock: 15.4 2003 Neon SRT-4 (stock): 15.3 @ 93 He never launched great, but either did my buddy in his LGT Even a 2004 Kawasaki Ninja 636 only did a 12.0 @ 119 So, as you can see, his 15.1 @ 89 with only a 2.0 60 foot time and hitting the rev limiter twice in rapid succession was pretty darn good. Oh, LACR is also at 2,710 feet in elevation. So with the elevation, the wind, and the warmth, and a basically brand new car, you can see the conditions were crappy. Oh, and my friend did say it was MUCH easier to launch the LGT than it was his EVO. If conditions were perfect, on a better track with a more broken in car, and better launches, I'd think the LGT would be capable of high 13's

[rao]

Interesting, accross the board those times are slow.

[Driver72]

Yeah, as I said, I'd never been to LACR, but was told straight off that cars run slow there. Oh, and another I forgot to list. A 2003 WRX with a cat back and a reflash (he said he's at 15.0 psi boost) got a 14.8 I didn't get a chance to write down his trap speed. They'd clear the board really fast. He got pretty good launch, for this track, though.

[Drift Monkey]

[quote name='rao']Interesting, accross the board those times are slow.[/quote] It was hot and at a high altitude. I can believe those times.

[Driver72]

Oh, one other thing LACR has an "altitude" adjustment factor listed too. I'm sure the way they got this number is universal. But they say, for their elevation (2,710 ft.) to multiply your time by .97 and your speed by 1.03 In my friend's LGT that would of meant a time of 14.64 @ 91.67 But this doesn't take into account the temp, the 20-30 mph winds, and the fact he not only had marginal launch of 2.02 to 60 feet, but he didn't shift into 4th and hit the rev limiter twice near the end of the track.

[rao]

Turbocharged cars would use slightly smaller correction factors (the et number would be larger and the trap speed number would be smaller). Either way, those are decent relative times and itlooks like everyone was uniformly slow that night.

[bigbadboss101]

Turbo are MORE affected by higher altitude, humidity, and high temperature? Can someone clarify? Thanks

[AreEyeSeeKay]

I think turbos are less affected by elevation since they are compressing the intake charge anyway, and more affected by Heat since the Intercooler (air-to-air anyway) is less efficient. Not Sure about humidity

[Driver72]

Yes, rao was correct, since turbos use "forced" induction, the fact that there is less "air" as elevation increases, has less of an impact on turbocharged cars. However, since it's relative, I'd believe the correction factor would be correct for both turbocharged and nonturbocharged cars alike. The correction factor is correcting the amount of oxygen in the air, so the decrease of oxygen is relative to both natural aspirated and turbocharged cars. It's just a bonus that turbocharged cars are affected less.

[rao]

Since the wstegate determines boost pressure relative to the outside pressure, turbo cars will not loose as much power due to altitude as NA cars or supercharged cars (whose boost pressure is not relative to the atmosphere but is fixed based on engine speed. If you remember, that was the hype supplied for Subaru surrounding the Forester XT "sking families car go faster up the mountain because of the turbo". The correction factor is different for the different types of car, but it is really not a huge deal becasue all of the times were slow ;)

[Driver72]

I didn't think boost from a turbo is determined by outside air pressue/density. The turbo should still build it's same amount of pressure and "push" that amount into the engine. Unless I'm wrong, the LGT, for instance makes 13.5 psi of boost and should no matter if you are at sea level or 8000 feet. I've never heard of there being a different factor for turbocharged cars. If that's the case, I'd love to know what it is. And why wouldn't they list that, since it appears nearly 1/2 the cars at the track were turbocharged or supercharged.

[inthedeck]

here ya go...check this thread out, and see if it makes more sense to you now... [url]http://forums.nasioc.com/forums/archive/index.php/t-206981.html[/url] [quote] The waste gate controls max boost above a preset limit This is a common misunderstanding possibly because of how turbochargers are used on some aircraft. The plumbing on some aircraft is substantially different than that used on an automobile. On many air craft the waste gate opening changes with altitude. It starts off wide open at sea level (ie no boost) and as the plane climbs the waste gate slowly closes so the turbo gradually creates boost to _exactly_cancel_ the effects of altitude. The result is the aircraft always acts as though it is at sea level until it reaches some critical altitude where the waste gate is completely closed. At that altitude you begin to experience loss of performance as the turbo charger can no longer provide enough boost to overcome the loss of outside air pressure. Actually this is not turbo charging but Turbo normalized to sea level performance. An aircraft with this configuration does not increase the engine performance above its basic sea level performance. This is I believe where people get the impression that a turbo completely eliminates the effects of altitude. On a car, and in some high performance aircraft like WWII fighter planes, the turbo is set up to substantially increase the total sea level power of the engine. The plumbing starts out like a turbo normalized plane at critical altitude. The waste gate is closed until it is told to open. As a result as soon as some exhaust flow rate is reached to spin the turbine, the compressor starts to build boost _above_atmospheric_pressure_ when you reach some predetermined boost pressure the waste gate opens so boost does not continue to climb. In the case of the stock turbo on the U.S. WRX it reaches critical altitude at about 13,600 ft. At this altitude even if you keep the waste gate closed all the time, it cannot achieve 14.5 psi boost. The thing a lot of people don't understand is that a turbo actually works on a pressure ratio. If the turbo is set to achieve a pressure ratio of 2:1 ( a nominal boost of 14.7 psi), then at sealevel it will create 14.7 psi boost above _local_ atmospheric pressure. You take the same turbo to 6000 ft and run it at the same rpm to create a 2:1 pressure ratio and you will only produce 11.78 psi of boost because that is the local air pressure you are doubling (under standard conditions). A turbochargers output mass flow is dependent on its compressor RPM and the density of the inlet gas. Higher density inlet gas, more mass flow out. Bottom line, a turbo makes up for about 1/2 the effect of altitude. If a NA 400 hp engine, looses 50 hp at some altitude, a 400 HP turbo charged engine (with no changes) will loose about 25 hp at this same altitude. To a limit you can dial up the boost a bit to compensate for this, but you quickly reach a point of diminishing returns. You dial up the boost by 10%, but because of loss of effeciency the turbo might only flow 5% more lbs of air even though it creates a boost pressure that looks like it should completely compensate for the altitude. ( more heating, higher rpm, more internal friction, higher exhaust back pressure etc. all cost HP ) Its just one of those no free lunch things. Turbos reduce power loss due to high altitude, but can't completely eliminate it. Does that make any sense ?? Larry" [/quote] later, i

[rao]

The above description is excellent. Here are the NHRA correction factors. [url]http://www.nhra.com/tech_specs/altitude.html[/url] Check out the notes for turbocharged cars.

[Driver72]

Thanks.

[Ridgeracer]

great link inthedeck....Also don't forget that hot air is harder to compress and cool vs. cold air in a turbo car. That along with the loss of efficiency in the I.C. causes some loss of power.

[Max Capacity]

I believe that track used to be Antalope Valley Raceway when I used to race there back in the late 70's. I seem to remember the cars ran about .7 of a sec. slower then at Orange County. Man that was a long time ago. But still have the memories.

[godwhomismike]

Damn, those times are slow across the whole board. At Englishtown, which is near me, Cobra's run 11's and 12's all day long here. Plus the motorcycles generally do 10's and 11's. I've seen one do high 9's at 161 mph. I wouln't put much weight on those times, except to say that you'll probably see a second shaved off that time at a better track with better conditions. - Mike

[05LegacyGT330Ci]

Englishtown gets some good numbers, especially in the fall when it is nice and cool out. Not everyone is so fortunate with conditions. But I remember when the Evo first came out the fastest stock Evo time was put down at Englishtown.

[firedawgs]

Nice thread, good info. I lived in CO for 4 years and know the affects of altitude. I am a firefighter and went to a fire apparatus class there. We learned that for every 1000ft in altitude you lose 2.5% in HP on nonaspirated engines, I am not sure on the aspirated cars.

[Xaqtly]

Yeah the bottom line is that LACR sucks. I've been there a few times too, and the heat, elevation and wind is really annoying. On a good day with no headwind and moderate temps, your times at LACR will still be a minimum of 4 tenths slower than at a sea level track.

[3.7L H6]

lets wait for some pro runs in cool, still weather. then we'll see 14.0.

[Driver72]

[quote name='3.7L H6']lets wait for some pro runs in cool, still weather. then we'll see 14.0.[/quote] I think 13's from a stock LGT are possible. Like I said, my friend got 15.1 at LACR in the worst conditions, with a 2.02 60 ft time and not shifting into 4th banging the rev limiter twice before crossing the stripe. That alone probably cost him .2 tenths. And this was with only 1200 miles on the car. On a good track, closer to sea level, on a cooler day, with still air, and a good launch, I can easily see 13.8 or 13.9 on the stock LGT with a few grand miles on the odometer.

[Ninjapimp]

[quote name='05LegacyGT330Ci']Englishtown gets some good numbers, especially in the fall when it is nice and cool out. Not everyone is so fortunate with conditions. But I remember when the Evo first came out the fastest stock Evo time was put down at Englishtown.[/quote] The fastest times from my VW days were almost exclusively had at Englishtown. Easily 75% of the top 1.8 turbo times. I used to think everyone was lying because they were no where near those times in my neck of the woods.

[dv8ingvector]

[font=Times New Roman][size=3]Ok there are my time slips in the order I ran. This was at New England Drag Way, the air temp was in the mid to upper 60s, the track is 90ft above see level, the cars race wait was 3668lbs, and this is in a stock 05 2.5gt auto wagon.[/size][/font] [img]http://www.sureelfilms.com/carstuff/05_2point5AutoWagonETs.jpg[/img] [font=Times New Roman][size=3](from left to right)[/size][/font] [font=Times New Roman][size=3]Slip #1[/size][/font] [font=Times New Roman][size=3]Ok this was my first run ever with the car. I was planning on launching at 3500rpms. However after talking with a scooby tech that happened to be at the track I was worried about over heating my tranny on multiple runs so I launched at 2500rpm and manually shifted only using 1-2-and-3 holding untill 200rpm before the rev limiter to compensate for the auto trans lag and void hitting it.[/size][/font] [font=Times New Roman][size=3]Slip#2[/size][/font] [font=Times New Roman][size=3]On this one I wanted to se how it ran in full auto however my foot slipped off the break early and car was only at about 1800rpm…car really lags at launch in auto mode regardless I have noticed.[/size][/font] [font=Times New Roman][size=3]Slip#3[/size][/font] [font=Times New Roman][size=3]Launch was the same as #1 but was shifting earlier to used 4th bad idea lol[/size][/font]

[Ninjapimp]

Jeepers! I don't know what you were running against, but DAMN! it's quick.... ;)