2015 Car & Driver Lightning Lap at VIR

[KaBoom1701]

Love it.

Chevy kicking ass these days.

[ssrs2lt]

Wow that's an awesome beast

[khell86]

Originally Posted by Stingray

Nope this is the Z06 that'll absolutely annihilate a 2012 Ford Focus off the face of the North American continent and beyond... J/K

The new Caddys are not to take lightly neither... beware M's and AMG's and S-lines. And even you Hellcat.

Hey man I bet a 2016 Focus RS would give the Z06 a run for its money... for about 100 ft

[Stingray]

Originally Posted by khell86

Hey man I bet a 2016 Focus RS would give the Z06 a run for its money... for about 100 ft

Hey it's all good... I like the new RS! That's going to be a cool quick car.

[Bhobbs]

Originally Posted by BaylorCamaro

Oh and the 5th gen 1LE is 3.7 seconds faster than the 2015 Mustang GT, doesn't look like it was the performance pack, guess we'll see when this article is published. But it's important to note that the 1LE ran that time in 2013, VIR was redone making it a slightly faster track in 2014.

I'm pretty sure Lightning Lap is done with all performance options available. If that's the case, it must be a Performance Package GT.

[strykerg8gt]

I'd like to know how the 8 speed auto would have faired in this. It has already shown to be faster in the 1/4 mile than the 7 speed manual. The Porsche 918 Spyder that holds the record uses a dual clutch paddle shifting 7 speed, and I'd venture a guess that the rest of the supercar field used some sort of similar transmission. Level the playing field by giving the Vette the quicker shifting 8 speed auto and I'd say that 2:43.1 that the 918 Spyder put down last year might be in jeopardy.

[Scott@Bjorn3D]

The auto has been having overheating problems at the track. Several reviewers commented the Z06 was fast but the auto shot craps and broke down in several track review test.

Never been a problem for the manual.

[Pushrod Pete]

Impressive numbers across the board for GM.

[strykerg8gt]

Most impressive part for me was that all 4 of the GM entries (Z06, ATS-V coupe and sedan, and CTS-V) posted sub 3 minute marks on the course, something BMW has never done with any of its cars. Not to mention the CTS-V set the record for sedans in the test. The CTS-V also beat the time that the Audi R8 V10 Plus put down last year, just flat out impressive for a 4100lb sedan.

[MEDISIN]

Originally Posted by BaylorCamaro

It's a known issue...

Originally Posted by RLHMARINES

Automatics are the only ones that I'm aware of that have this issue.

Originally Posted by Scott@Bjorn3D

The auto has been having overheating problems at the track. Several reviewers commented the Z06 was fast but the auto shot craps and broke down in several track review test.

Never been a problem for the manual.

Let's keep this "overheating" in perspective. I assume you're referring to Pobst's hot laps at Road Atlanta earlier this summer? This was brought up in a Q&A with Tadge Juechter.

Question was asked:

Could you describe what occurred to the car that the media ran at road atlanta back in November 2014. It seems several magazines have quoted having the over heating issue but no one clarified if it was the trans or the engine oil. I know from my personal experience that my car did get pretty warm on a cold 40 degree day there a few weeks back. I and many people are concerned we will see issues come this summer without mods.

Tadge answered:

There are lots of interesting back stories behind recent media tests, but the question asks about Road Atlanta so for the purposes of this thread I will focus on our long lead media event last November. We spent a week there with journalists from around the world. We had pro drivers Tommy Milner, Randy Pobst, and Andy Pilgrim behind the wheel along with many other very capable drivers. They were permitted to run consecutive laps with minimal or no traffic, so essentially "qualifying laps". Over the course of the week we had 2 cars come into the pits with a hot warning messages. The first was due to the loss of an accessory drive belt. We had a pre-production tensioner on that car which failed, throwing the belt and we lost the water pump. We have had no issues with production tensioners. The second car was an automatic. I believe it was being driven by Randy on the hottest day there which was right around our design performance target of 86 degrees (more on that below). After multiple laps at speed he came in with a hot warning message. Although the car had been out on track all week, that was the first and only incident. In Corvette's 60 year history, we have never put automatics on track for media and never encouraged people interested in track usage to buy automatics. The new 8 speed automatic gives us a chance to put more automatic transmission customers on the track. Since there is some lack of clarity around the true capability of each of the transmissions, this question gives us the opportunity to publish some guidelines.

The Z06 Manual is designed to keep engine oil, coolant, transmission and differential fluids below the hot warning targets when driven by a professional on a 30C day (86F) on a "typical" racetrack for an indefinite period of time (effectively the time to burn through a full tank of fuel). Our team validates the durability of the Z06 cooling systems with a 24hr accumulated track test to simulate the most aggressive track-day usage by our customers.
We designate our track: the Milford Road Course, as the "typical" standard, but recognize that there are tracks around the world which are easier on a cooling system and some which are harder on a cooling system. Generally speaking, tighter tracks with lower average speed and higher sustained RPM, will drive higher fluid system temperatures.
Higher temperature ambient conditions affects all car's abilities to run sustained laps at ten-tenths.

The Z06 Automatic transmission put in "Drive" selects the lowest possible gear ratio for best acceleration, and because it has 8 closely-spaced ratios typically runs higher average RPM than the manual. This optimizes lap time performance, but also taxes the engine oil and coolant more for any given track. So the automatic has the capability to run faster laps than the manual, but thermal limitations are reached more quickly. Customers who are planning to run extended track-day sessions at 'professional' speeds, are advised to go with the manual transmission, or to paddle shift the automatic and select higher gears when conditions warrant it.
Any time the maximum recommended temperatures are reached in any condition, the DIC will give warnings at the appropriate time for coolant, oil, or transmission fluid. A cool-down lap or two will bring operating temperatures back to a reasonable level and aggressive track driving can be resumed.

Some may wonder why don't we design to higher temperatures, say 110 degrees, to accommodate southern tracks in the Summer. We have used the "pro driver at 86 degrees" criteria for generations of Corvettes and for the vast majority of customers, it has resulted in excellent performance for their usage. If we designed to higher temperature criteria, we would have to add a lot of cooling hardware which drives mass up and perhaps more importantly, you have to feed the system with more air which has a huge impact on appearance and aerodynamic drag. Like most aspects of car design, the challenge is in finding the best balance of conflicting requirements.

During testing (vs the GT-R) at Willow Springs, Randy Pobst commented on the Z06 automatic and heat production.

As in previous tests, the Z06 got very hot during lapping and pulled power. Per Pobst: "The power starts to fall off significantly after the first lap. It was nearly pegging the oil temp gauge after a few laps. 320 degrees. I did a cool-off lap and it came right back down." We checked the data, and lap times and peak speeds did fall off by a few tenths of a second and 1 or 2 mph on each subsequent lap , though these could also be attributed to tire wear and other factors. Although Pobst has consistently complained of reduced engine power when lapping C7 Z06s, the problem does not appear to be especially great (in terms of lap times) and only seems to affect drivers of Pobst's incredibly high skill, suggesting that most customers won't encounter it.

Read more: http://www.motortrend.com/roadtests/...#ixzz3lLGKqs26

Note: the CTS-V in this years Lighting Lap also combines the LT4 + 8L90 and did not experience heat-related issues in 100F weather. The authors note both Mustangs suffered from the heat.

[Stingray]

^ Exactly... too many who don't even own one let alone track the car easily jump to conclusions. There's no denial regarding the need for more robust cooling... but statements such as "won't last more than one lap" is inaccurate. Many drivers (not named Randy Pobst) won't experience overheating temps while those that did is also due to high ambient temps or adverse conditions or other factors in play such as lack of track prep, etc.

If you don't believe me... then come down to south FL and I'll take you as a passenger for 30 minutes in very fast hot laps in the advanced group. You can can eyeball my car's temps nonstop while I accelerate and corner hard enough for you to get nauseous... or even puke.

[shawn18]

Bench racing's ..benchmark. Cool to see the numbers though.

[GretchenGotGrowl]

It is my impression that most of the people having the A8 overheating issue have Z51s. The Z06 has more cooling (they evidently are adding some for the 2016 Z51) so they seem to have more issues from the SC and heat soak. That's too be expected an it doesn't seem to affect lap times that much. JMHO

[Bongos2U]

Here is a partial quote from Car and Driver Lightning Lap #1 about the Mustang Ecoboost.
"...We're thinking that a few of the engine's claimed 310 ponies ended up at the glue factory".

Priceless.