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Max Online: 36 @ 05/16/08 05:15 PM
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For the first time, General Motors Co. studios across the world have submitted design studies for the next-generation Chevrolet Corvette.
Late last year, Ed Welburn, GM's vice president of global design, invited GM's 10 styling studios to submit design proposals.
Some "were absolutely phenomenal," Welburn said. "There is a lot to pick from. The direction that we take is very important, and the decision has not been made."
Global input on the Corvette's design is one of several steps GM is taking to attract buyers in Europe, where the car has little appeal, and young U.S. buyers who favor imports.
"We have challenges in the States with the Corvette," Welburn said in an interview at the Geneva auto show. "The average age of the customer is really rising."
The current average age of a Corvette buyer is 54, according to the Power Information Network, a unit of J.D. Power and Associates.
Corvette sales are in a tailspin. Last year 13,934 were sold in the United States, down 48 percent from 2008.
The current Corvette debuted in the 2005 model year. Prices range from $49,880 for the base coupe to $107,830 for the ZR-1. Both prices include shipping.
A redesign is due in two to three years, industry sources say.
Corvette critics often cite the sports car's size, saying it looks big. They also point to what they say is a cheap-looking interior.
Welburn admitted the interior has a problem: "The execution, materials selection -- it's got to be a much better interior. Our customers desire that."
Welburn said today's Corvette is about the same size as the Porsche 911, but the styling makes it look bigger. "We have to develop a design that feels trimmer, meaner, to go along with the incredible performance that the car has," he said.
In addition to styling, content, pricing and marketing strategy are under discussion, he said.
"It is a key time in the development of the Corvette," Welburn said. "There is a lot of debate and a lot of study on the bandwidth of Corvette."
But, he added, "It can't mutate into something that gets so far away from Corvette that it is no longer a Corvette.
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Of the 2010 ZR1s made so far the choice of paint colors by the buyers has been :
1. Black ---------------------- 157 units
2. Cyber Gray Metallic ----- 72 units
3. Torch Red ----------------- 66 units
4. Arctic White --------------- 46 units
5. Jetstream Blue Metallic - 46 units
6. Crystal Red Metallic ------ 42 units
7. Blade Silver Metallic ------ 34 units
8. Velocity Yellow ------------- 26 units
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We have posted in the past the ill effects of being forced to use E10 gas ( feds require E15 by mid year) for performance as it takes more volume of E10 to produce the same level of energy then straight gas.
Where straight gas at part throttle would require a 14.7:1 AFR due to E10 causing a leaner AFR for best performance the NON WOT engine conditions for EPA would require at the least the PCM tuned for a richer AFR of 14.2:1
We obtained straight 91 octane gas to compare it to other tests where E10 was used to see what the effects are
The PCM had been tuned for E10 so that the fuel trims which were at 8% too lean back to around zero
Leaving that tune in and using straight gas and the engine being 11.3:1 compression we see where the fuel trims were at zero with E10 that now with straight gas the average fuel trims are now -5% rich with a maximum of -11% too rich.
Notice WOT timing was at 29 degrees, zero knock and misfire.
Clearly gives a image that in using E10 your PCM would be running 5 to 10% too lean ( leaner in hot weather) which induces engine knock and lower timing to reduce HP and Tq
Since E15 will be required by EPA around mid year you can expect your engine to be running even leaner and less performance unless you tune the PCM to solve the issues of using ethanol
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Camshaft timing gears:
A - Single bolt 4X camshaft gear from a 2007-2009 LS2 or LS3
engine
B - Three bolt 4X camshaft gear from a 2006 LS2 Corvette or
from a 2006-2009 LS7 Corvette engine
C - Three bolt 1X camshaft gear from a 2005 LS2 Corvette or a
2005-2006 LS2 GTO/SSR/Trailblazer engine
D - Three bolt camshaft gear from a 1997-2004 LS1, LS6 or other
Gen III V8 engines.
No reluctor teeth are on the timing chain gear since the camshaft position sensor is at the back of the block and senses the camshaft speed from the reluctor machined
into the back of the camshaft itself.
Crankshaft reluctor wheel images:
Left image - 24X crankshaft reluctor wheel found on
all Gen III V8 engines (LS1, LS6, LQ4, LQ9) and
early Gen IV V8 engines (2005 LS2 Corvette,
2005-2006 LS2 GTO, 2005-2006 LS2 SSR).
Right image - 58X crankshaft reluctor wheel found
on later Gen IV V8 engines (2006-2007 Corvette
LS2, 2006-2009 Corvette LS7, 2008-2009
Corvette LS3 etc.)
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The cop should not have been driving over the legal speed limit, his own driving actions could have killed others all over revenue collecting. 
Cars without N20 have been ticketed for speed so stupid to blame it solely on N20 as a cops action to write a speeding ticket
ACKSON -- House members overwhelmingly approved legislation Monday that bars nitrous oxide, which one legislator called "like a vehicle on steroids," in memory of a state trooper killed last May while chasing a Pontiac Trans Am equipped with the gas.
With Master Sgt. Steve L. Hood's widow and children watching from the gallery, House members approved the legislation by a 109-9 vote.
The measure, called the "Trooper Steve Hood Act: The Nitrous Prohibition Act," was amended to give judges and prosecutors discretion in handing out punishment, which was set at up to a $1,000 fine and 48 hours in jail for the first offense.
The legislation goes back to the Senate, where it had been approved earlier, for concurrence with the amendment.
"Nitrous oxide is something that increases speed of vehicles," Rep. Donnie Bell, D-Fulton and vice chairman of the Transportation Committee, told fellow legislators.
"This is like a vehicle on steroids."
Hood, 50, was chasing a Trans Am driven by William A. Francis, 25, when the trooper crashed into a tree on state Miss. 371 in Lee County.
The driver escaped but was captured later.
Francis, of Baldwyn, was charged with felony escape and manslaughter.
Troopers said the Trans Am was traveling at speeds over 100 miles per hour when Hood spotted it and chased.
Hood wrecked his patrol car and died in the crash while the Trans Am driver and three passengers escaped.
"The Mississippi Troopers Association had come to me about the possibility of bringing this up and naming it after him," said his widow, Lisa Hood of Guntown, Miss.
"And, of course, I was more than glad to do that for the protection of my son, who wants to go to patrol school himself."
Lisa Hood said her husband, who had just turned 50, had been with the Highway Patrol for 26 years and was thinking about retiring a month later.
"We want to make the streets and roads safe for all of them," she said.
Nitrous oxide, widely popular with street racers, is a chemical compound used to increase the output of engines by allowing them to burn more fuel than normal.
NASCAR outlawed nitrous oxide in 1976, but it is still used in many classes of legal drag racing.
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Goodyear's Newest Eagle Flies on 2011 Corvette
AKRON, Ohio, Feb. 4 /PRNewswire-FirstCall/ -- The Goodyear Tire & Rubber Company (NYSE: GT) is announcing its newest ultra-high performance tire, the Eagle F1 SuperCar G:2, and its arrival is boosted by the achievement of an original equipment position on the 2011 Chevrolet Corvette Z06.
The new Eagle F1 SuperCar G:2 builds upon a three-decade relationship between Goodyear and Corvette.
For Corvette owners and other enthusiasts who demand the most from their performance automobiles, the Eagle F1 SuperCar G:2 is "street-refined, but track-capable," according to Bob Toth, Goodyear's director of new products.
An asymmetric, directional tread design with massive tread blocks on the outboard shoulder help enhance dry cornering grip, while sweeping Aquachannel grooves on the inboard side of the tread help enhance wet cornering grip.
An innovative multi-radius mold shape helps to offer precise handling and smooth, even wear.
Even the appearance of the tire is important; a serrated band sidewall styling and distinctive lettering add to the overall ultra-performance look.
"The new Eagle F1 SuperCar G:2 is positioned as a race-inspired, ultra-high performance dry traction tire for select supercars.
With a left-side, right-side specific tread design, it offers superb dry traction and precise handling, complementing both the performance and appearance of sports cars," Toth said.
The tire, tested on some of the most renowned road courses in North America, will be available this summer in these run-flat sizes: P275/35ZR18 and P325/30ZR19.
SOURCE The Goodyear Tire & Rubber Company
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We had a C6 customer who had odd problems where the car battery was draining even more then the normal problems.
In doing diagnostics we traced the problem down to a product this cyberspace vendor sells for $99 which is a simple wireless product that comes with 2 key fobs and a remote receiver that switches a single circuit on or off and used to force the baffle in the mufflers to be open when normally they would be closed
All this does is make the exhaust louder. Read the writeup and test results in the Z06 section as how badly doing this at low engine loads.
This Southerncarparts makes all kinds of claims see
Junk product
When doing research we find the real seller and in fact they make a profit selling this at only $21!
You can imagine how little is in this design and reason why it is common for the receiver to get stuck in a closed / on state and dragging the battery down.
I'd also suspect at a profit made at that low price the product may be made in China
Look closely at Southerncarparts image of the key fobs, notice the red marking at the bottom edge and then with this vendor and the same exact markings and the key holders are the same.
Real Maker
Here is the image of their $21 product
No sense if doing this to be paying someone many times what the real retail price is
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Those using boost believe that they need to run at very rich mixtures.
The theory is that the excess fuel cools the intake charge and therefore reduces the probability of knock.
It does work in reducing knock, but not because of charge cooling.
First let’s look at the science.
Specific heat is the amount of energy required to raise 1 kg of material by one degree K (Kelvin, same as Celsius but with 0 point at absolute zero). Different materials have different specific heats. The energy is measured in kJ or kilojoules:
Air ~ 1 kJ/( kg * deg K)
Gasoline 2.02 kJ/( kg * deg K)
Water 4.18 kJ/( kg * deg K)
Ethanol 2.43 kJ/( kg * deg K)
Methanol 2.51 kJ/( kg * deg K)
Fuel and other liquids also have what's called latent heat. This is the heat energy required to vaporize 1 kg of the liquid.
The fuel in an internal combustion engine has to be vaporized and mixed thoroughly with the incoming air to produce power. Liquid gasoline does not burn.
The energy to vaporize the fuel comes partially from the incoming air, cooling it.
The latent heat energy required is actually much larger than the specific heat. That the energy comes from the incoming air can be easily seen on older carburetor cars, where frost can actually form on the intake manifold from the cooling of the charge.
The latent heat values of different liquids are shown here:
Gasoline 350 kJ/kg
Water 2256 kJ/kg
Ethanol 904 kJ/kg
Methanol 1109 kJ/kg
Most engines produce maximum power (with optimized ignition timing) at an air-fuel-ratio between 12 and 13. Let's assume the optimum is in the middle at 12.5.
This means that for every kg of air, 0.08 kg of fuel is mixed in and vaporized. The vaporization of the fuel extracts 28 kJ of energy from the air charge.
If the mixture has an air-fuel-ratio of 11 instead, the vaporization extracts 31.8 kJ instead. A difference of 3.8 kJ.
Because air has a specific heat of about 1 kJ/kg*deg K, the air charge is only 3.8 C (or K) degrees cooler for the rich mixture compared to the optimum power mixture. This small difference has very little effect on knock or power output.
If instead of the richer mixture about 10% (by mass) of water would be injected in the intake charge (0.008 kg Water/kg air), the high latent heat of the water would cool the charge by 18 degrees, about 4 times the cooling effect of the richer mixture.
The added fuel for the rich mixture can't burn because there is just not enough oxygen available. So it does not matter if fuel or water is added.
So where does the knock suppression of richer mixtures come from?
If the mixture gets ignited by the spark, a flame front spreads out from the spark plug.
This burning mixture increases the pressure and temperature in the cylinder.
At some time in the process the pressures and temperatures peak. The speed of the flame front is dependent on mixture density and AFR.
A richer or leaner AFR than about 12-13 AFR burns slower. A denser mixture burns faster.
So with a supercharger under boost the mixture density raises and results in a faster burning mixture. The closer the peak pressure is to TDC, the higher that peak pressure is, resulting in a high knock probability.
Also there is less leverage on the crankshaft for the pressure to produce torque, and, therefore, less power.
Richen up the mixture results in a slower burn, moving the pressure peak later where there is more leverage, hence more torque.
Also the pressure peak is lower at a later crank angle and the knock probability is reduced. The same effect can be achieved with an optimum power mixture and more ignition retard.
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.
This is why running overly-rich mixtures can not only increase fuel consumption, but also cost power
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Here is several head designs GM sells
12480090
Bare C5R Racing Cylinder Head
355-T7 'as-cast' Aluminum racing head
Professional porting and machining of combustion chambers required
No seats or guides
C5R rectangle port design requires aftermarket rectangle port intake manifolds
Designed for 2.180/1.625 valves
11' valve angle
Machined for 1.625 diameter valve springs & .500 guides
Designed for big bore (4.100 min) LS7/C5R/LSX blocks
210cc 'as-cast' intake ports
70cc 'as-cast' exhaust ports, same as production LS6
30cc 'as-cast' combustion chambers
All fasteners are metric
Valve cover rails have O-ring groove for .125 O-ring
Capable of over 800 horsepower!
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1 registered (1 invisible),
6
Guests and
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Spiders online. |
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Key:
Admin,
Global Mod,
Mod
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