Warp Factor

No, it states what the car driver believes is the high threshold for coolant only, given the specified rules and environment, placing particular emphasis on "drafting" behind other cars, which will reduce cooling airflow.

SBC_and_a_stick

Ok, but you are confusing the systems maximum ability to pull timing with what it should do given sensor inputs. The oddity is that it will sometime pull 30* more in the same conditions.

Do you think a Corvette should max out timing pull on a 65* day, 195* coolant, 190* oil, and 3,500rpm. How is it going to pull more timing on a hot day on track if it pulls all the timing it can on a bridge going 50mph on a cold day?

I prefer the old school stuff that just worked mechanically and didn't have to rely on nannies to save the day and shut off the party before it gets started. Worked better for everyone. A water pump/circuit that doesn't cavitate and doesn't need smarts to shut off the party, forged titanium rods that don't need 50 weight oil to keep the rotating assembly alive. A proper charge air HE that while taller doesn't starve the back cylinders of cool air. You are all alone on a future where you don't have hardware to run hard for more than 10 seconds and you effectively detune to Cobalt levels of performance after that.

Ok, let's try again, the quote is:
"I don't think you can stay together at all," said Kyle Busch. "We're running 230, 240 [degrees water temperature] just pack drafting and then once you get pushed from behind or you have somebody close to you, it kind of moves you forward a little bit to the car that's in front of you. You're already 245, 250. That's already borderline for our engines.

"You can probably take them to 260, 265 on water temperature before you start pushing water, but we don't want to jeopardise that and push water too early in the race and run ourselves out of water. Our limit is about 240 [degrees] until two [laps] to go."

245-250 is "borderline for [their] engines."

Water starts to boil sometime after 260-265. If you don't "push" water until 260-265 then why limit driving to keep water under 240*? I think the answer is that it is "borderline" for the engine.

If we know their PSI we could even calculated when water is starting to boil. I bet it's not 240* but sometime after 265* as stated in the article.

Warp Factor

I will eagerly await your evidence that a C7 Z06 pulls all the timing it is capable of doing, aside from really low-quality fuel being involved.

I sometimes have a hankering for the old-school stuff too.
When I was learning to drive, a single poorly-executed power-shift could be the end of everything that mattered to to me, at that time.

Forged titanium rods have almost nothing to do with oil weight. Aluminum rods, under really low temperature startup conditions, can contract enough that they can reduce bearing clearances enough to cause problems.
I'd recommend some better sources for leaning, than those you have hung your hat on so far.

SBC_and_a_stick

Sure.

LT series can pull 60* of timing max:
"All Gen V engines are built with variable valve timing that offers an enormous swing of over 60 degrees of authority over the camshaft position. [...] But with VVT, GM can now move the cam over an incredible 62-degree range of authority." http://www.superchevy.com/how-to/eng...evy-lt-engine/

Choosing forged titanium rods instead of forged steel rods in the LS engine family allowed Chevy to specify the same 10W30 oil weight:
http://www.corvetteactioncenter.com/...7-engine6.html

johnglenntwo

Some of these guys see a benefit in second guessing GM's engineering.
Figure out how to flog the sucker for all it's worth, take care of your responsibilities - And let your Warranty begin! (And don't be a Troll!)

YOUR DISORGANIZATION SERVES GM'S AGENDA!

Thanks again so much!

Warp Factor

GM can pull any amount of ignition timing that they want to. There are tradeoffs to be taken into account, like higher heat loads when the ignition timing is reduced too far.

You've kind of fluffed over your transition from ignition timing, to camshaft timing, (including variable camshaft timing). Camshaft timing is a whole 'nother can of worms.
What would you like to put your focus on in this thread?

SBC_and_a_stick

Right, I guess I don't know how much ignition timing can be pulled. I simply took my logs and compared a grueling track day when the car did work without intermittent power with logs taken on the road when the car has intermittent power issues but the conditions are pretty ideal. Something causes it to freak out and pull substantial timing, far more than it would do on track. It also knocks, but when I say this I don't mean audibly or at least I can't tell. There is another output in the log that is knock retard. I can see it knocks from time to time and almost always with the throttle pinned. That's all I can say, and I don't really have a cure for it that I can show. I'm not an engineer which is why I was relying on warranty to keep the car running properly. I'm only talking about this intermitent power issue because Bill brought it up.

I don't have a good answer to what if any a similar approach to the Porsche guys can be taken. I'm literally overwhelmed by troubleshooting. My take is that I had to retire the car. I actually did buy the the 7 year warranty for the car but I soon realized it doesn't actually fix the design challenges, and there are too many to deal with.

johnglenntwo

Bad Gas or Hot!

SBC_and_a_stick

It's been doing this for a year now on 91 octane, many gas stations. It also hesitates on throttle on 95 octane, just a bit less. As I mentioned before it also hesitates in ideal ambient conditions ~65*. But yes, there is something heat related as it runs best as it warms up for the first few minutes. Once it starts oscillating power there is no stopping it.

johnglenntwo

Make sure your ducks are in a row and flog-on as much as possible. And remember like an officer with a Vette once told me up here, "It has enough to get me in trouble!"

THE ORIGINAL AIR BUBBLE THREAD?
This was before Gspeed's cavitation determination:
https://www.corvetteforum.com/forums...oler-tank.html
It's again not your problem, and a warranty issue!


AND ANOTHER TANGIBLE WARRANTY ISSUE!
A valve job is an operation which is performed on any four stroke cycle, internal combustion engine, the purpose of which is to resurface the mating surfaces of the poppet valves and their respective valve seats that control the intake and exhaust of the air/fuel mixture that powers the motion of the pistons after the start cycle.

In the earliest automotive engines, the valves needed to be removed and the sealing surfaces sanded, ground or lapped multiple times during the life of a typical engine. As the decades passed, however, engines ran cleaner and the addition of tetraethyllead in gasoline meant that such maintenance became less frequent. Today, valve jobs are rarely done on passenger cars for the purpose of maintenance, although they are still quite common with high-performance cars. Some reasons that may induce the need for a valve job in a modern passenger include: excessive RPM, high mileage, overheating, material failure, and foreign object damage (FOD).
https://en.m.wikipedia.org/wiki/Valve_job

HPT

Her G-Wagen was more.

johnglenntwo

That suckers MPG is obviously.....

YOUR WELCOME!

johnglenntwo

https://www.quora.com/How-does-overh...e-a-car-engine

NicD

Are people seriously comparing the Porsche blown motor issue to the C7Z overheating at the track? One is a $50k motor replacement and the other you just wait until it cools down and you drive it home.

Jesus if it's really that much of an issue either spend the money on a better cooling system or sell the car and find another one that fits your criteria better. Hell most cars are going to need cooling upgrades anyways for hotter weather if pushed hard enough. For a serious track rat the aftermarket cooling system upgrades are well worth it and less than actually racing in events between gas, tires, brakes, etc. Bitching about it on the internet won't fix a thing and nobody is going to change anybody's mind on the situation.

johnglenntwo

I think that takes your involvement to another level, but, again I will take this moment to reiterate and make it clear, "I really do prefer the gals!"

johnglenntwo

Yep, just like the rev limiter and traction control on the C5 put more in our hands, Autonomousness will too.
If the Vette program makes it!?
Dribble aside you can hit the spot - !

Warp Factor

"Johnflenntwo", do you have a job, and have you been taking your psychosis meds on schedule?

b4i4getit

This would never happen with GM since it would cost too much. This company is not about goodwill, its about profit.

rikhek

Word!

johnglenntwo

Doesn't a boat have cooler water pouring through its systems!? Emissions!? Does it have all of a street cars condition variables!? Will it be running and degrading like the Vette on track, or will it just be running consistently! etc! etc!

Some people (usually originally standard learning disabled) can think of three or more concepts at once, and some people have trouble with just one - !