2014 C7 Chevrolet Corvette

[thorlius]

Originally Posted by CTB727

I hate the Camaro taillights. Everything else looks good. And it's about time they updated the interior so it doesn't look like it's from a Cobalt.

This exactly. The sunglasses are cartoonish and lame for a sports car. Even the Camaro (I used to frequent the camaro5 forums) guys mostly hate the taillights like that.

The rest of the car looks great.

I drove a Cobalt as a winter car and a C6 as a summer car before selling the former and trading in the latter for the FR-S, and agree 100%. Identical steering wheels was a joke.

I'm pretty happy I made the deal as I would have been very jealous of the C7s on the road if I was driving around in a base C6.

[ZDan]

Originally Posted by serialk11r

450hp is pretty good, but the point was that they gave it truck cams which defeats the purpose.

Max power at 6000rpm => not a truck cam.

If the target is 450hp, use a 5.5-5.7L engine, not a 6.2, and save some cost, mass, fuel, and engine compartment space.

Weirdly enough, one reason they stuck with 6.2 is for fuel efficiency. It will be able to run more of the time as a 4-cylinder than if they'd made it a 5.5.

All else equal, to use a bigger engine to make the same power makes very little sense when you have enough torque to spin the tires off the line.

Torque at the wheels includes torque multiplication from gearing. A 450hp 5.5 would definitely be lower-geared than the 450hp 6.2. Actual torque at the wheels would be similar.

[Dave-ROR]

I hate the rear end, but I'll drive one and would consider buying a Z51 7MT car. In the end I'll probably have the same complaints I always have about modern Vettes.

[Dimman]

Originally Posted by Draco-REX

I can spin the tires off the line in my BRZ with 150lb/f of torque, that argument is kinda meaningless...

As for cost, mass,and engine space, a 5.7 or a 6.2 will take up the same amount of space. The difference in displacement is a matter of cylinder bore and stroke. The block size will stay the same.

The Vette's strength is it's torque and ability to exit corners better than its competition. Going to a small displacement low-tq, high-hp engine just because that's what the europeans do won't do it any favors.

If the engine was optimized as a smaller displacement, it would be smaller, lighter and rev better. Smaller bore with same wall thickness will be shorter longitudinally. Shorter stroke means the lower crankcase can be shorter/engine can be lower. And since the deck height is based on rod length which is also based on stroke, it too would be less, meaning shorter height and narrower width. Plus less rotating inertia from smaller/lighter internal and reduced stroke diameter.

Not saying it would be a massive amount, but it would be smaller and lighter.

[LIKEABOSS]

Laguna Blue with Black Wheels Please!

[BMWDavid]

OK...as the OP of this thread I'm going to chime in here. My first impression is not very good. Car is very flashy, the red is shocking but the gray car in the background did look more mature. I'm not sure about the interior. Going to need to see this car in the flesh.

I know this was a proto-type hence all of the trim fitment issues on the display car. But still you would have thought that GM would present a better first look.

It would have been better to wait until they had the car more dialed in perhaps.

So for now I don't have a case of "gotta have it".

[WingsofWar]

a little bit of analysis on my end..

i love the new C7 corvette, and wears the Stingray Insignia well. Why?

Stingray emblem represents a corvette that is designed for performance. It wants to evolve, and go against the grain, its tradition. It isn't about styling its about an ideal.

The C5-C6 were failures in this because they were focused on a tradition. Which is probably one of many reasons why none of them wore Stingray badges.
The C7 is an evolution of the Corvette, not a child of the Corvette.

From this picture, i do have 2 major issues...
1. The rear end looks horribly designed.
2. the rear vents in question look like they could feed air to an oil cooler..like a transmission oil cooler...rather than serve as a brake cooling ducts. They are much to high to have any real connection to the rear brakes.

[Ryephile]

Like any emotionally tied car, reactions have been all over the map. Those that want to be offended, are. Those that want to love it, do. Instead of being all emotional about it, how about we take a step back and look at the big picture.

The Corvette was in desperate need of a radical makeover. Yet another warmed over aesthetic dating back to 1984 would've been a white flag for innovation and much needed respect. They had to design in some shock factor to make people even pay attention. In this respect, GM has succeeded in getting people to pay attention and talk about it.

There are two obvious sides to the Corvette story; the long-time owners and the hopeful conquests [i.e. us]. Most of us want a car that fits our personal preferences rather than love the car for what it is. The died-in-the-wool owners are foaming at the mouth rabid and will either react strongly positively or negatively to the next generation. That's been consistent for generations of Corvettes, or any model for that matter.

The fundamentals of the Corvette as we've known it for a long time are still there; massive front-mid mounted V8 with rear transaxle, limited slip diff, transverse leaf springs, plastic fantastic body [in various executions] and classic long-hood/low-cowl/short-deck proportions. I'll add that it also has an innovative transmission [remember 4+3?], and a decidedly archaic slushbox [remember 4AT in early C6?]

Most of us are just bench racing and we won't even bother to realistically entertain buying the C7, so whatever bitching is just philosophical or academic. I really want to like the C7, and I'll go drive one when they hit showrooms later this year, but I'm not expecting anything either way. If it's good I'll appreciate it, and if not I'll be logical about it.


[warning rant]
All that said, I'll still provide my initial emotional feedback. I think the exterior looks fantastic; it's clearly at least one generation "newer" looking than the C6, and makes the C5 look bloated and flabby. The interior is a mixed bag. I like the materials, but the C4-facelift meets Supra Mk4-esque design isn't my favorite. I don't like interiors that segregate the passenger and invoke an aura of compartmentalization. I much prefer open interior aesthetics like the S2000, MINI, and Elise, where ergonomics and aura trump materials choices and decidedly irrelevant jet-fighter-inspiration.

While the idea of more power and better fuel economy is awesome on paper, in reality, how much power is too much? Would the Corvette had been better off eschewing the false pretenses of lap-times and gone slightly greener? I can't help but ponder, would a small 350HP V8 + 100HP IMA be a 1-2 knockout for both straightline and fuel economy, or is the demographic simply too ignorant or rebellious to accept such solution? In any case, the car that comes out will undoubtedly be amazing. The only question would be; is it what you're looking for?
[/rant]

[Ryephile]

Originally Posted by WingsofWar

....
2. the rear vents in question look like they could feed air to an oil cooler..like a transmission oil cooler...rather than serve as a brake cooling ducts. They are much to high to have any real connection to the rear brakes.

The press release states the rear fender inlets and taillight outlets are for transmission and differential heat exchangers in the Z51 package. The rear brake cooling ducts are beneath the side sills.

[M-17]

Originally Posted by Ryephile

Like any emotionally tied car, reactions have been all over the map. Those that want to be offended, are. Those that want to love it, do. Instead of being all emotional about it, how about we take a step back and look at the big picture.

The Corvette was in desperate need of a radical makeover. Yet another warmed over aesthetic dating back to 1984 would've been a white flag for innovation and much needed respect. They had to design in some shock factor to make people even pay attention. In this respect, GM has succeeded in getting people to pay attention and talk about it.

There are two obvious sides to the Corvette story; the long-time owners and the hopeful conquests [i.e. us]. Most of us want a car that fits our personal preferences rather than love the car for what it is. The died-in-the-wool owners are foaming at the mouth rabid and will either react strongly positively or negatively to the next generation. That's been consistent for generations of Corvettes, or any model for that matter.

The fundamentals of the Corvette as we've known it for a long time are still there; massive front-mid mounted V8 with rear transaxle, limited slip diff, transverse leaf springs, plastic fantastic body [in various executions] and classic long-hood/low-cowl/short-deck proportions. I'll add that it also has an innovative transmission [remember 4+3?], and a decidedly archaic slushbox [remember 4AT in early C6?]

Most of us are just bench racing and we won't even bother to realistically entertain buying the C7, so whatever bitching is just philosophical or academic. I really want to like the C7, and I'll go drive one when they hit showrooms later this year, but I'm not expecting anything either way. If it's good I'll appreciate it, and if not I'll be logical about it.

Right there with you. I'll make a proper assumption once I can get behind the wheel on one of these.

[serialk11r]

Originally Posted by LSxJunkie

All else being equal.....except valvetrain?

It would have taken a lot more than 11.5:1 compression to make 450hp out of a 5.5-5.7 OHV motor and still hit the fuel mileage and drivability goals they were looking for. That's a midrange aftermarket cam. No smooth idle, no 26+mpg highway, certainly no 17mpg city.

It's not that simple when it comes to cams, it is possible to get better gas mileage and more top end power. With 11.5 compression and cylinder deactivation, idle shouldn't be a problem if overlap is kept in check.

Originally Posted by Draco-REX

I can spin the tires off the line in my BRZ with 150lb/f of torque, that argument is kinda meaningless...

As for cost, mass,and engine space, a 5.7 or a 6.2 will take up the same amount of space. The difference in displacement is a matter of cylinder bore and stroke. The block size will stay the same.

Uh, I'll believe it when I see it. Clutch drops don't count. Mind you, the BRZ also has a front weight bias and skinny tires, but I still don't believe you if you say that flooring your BRZ on smooth, dry pavement in a straight line makes the tires spin. A 5.7 can be designed to take up less space than a 6.2 if they want it to, the crank can be smaller if the stroke decreases and the block can be smaller either way. The engine was designed from the bottom up supposedly so this is something they could've done.

Originally Posted by ZDan

Max power at 6000rpm => not a truck cam.

Weirdly enough, one reason they stuck with 6.2 is for fuel efficiency. It will be able to run more of the time as a 4-cylinder than if they'd made it a 5.5.


Torque at the wheels includes torque multiplication from gearing. A 450hp 5.5 would definitely be lower-geared than the 450hp 6.2. Actual torque at the wheels would be similar.

Max power is at 6000rpm, but max power is a weak 72.6hp/L at 6000rpm. My 15 year old Corolla engine with a lower rev limit, no direct injection, smaller cylinders (inherently lower efficiency at max load) does better than that at its 6000rpm power peak. Furthermore, they were bragging about the torque from 1700rpm and up or something, another indication that the cams are very much low end focused. The power peak being at 6000 just tells you that the friction and combustion are better optimized so that the power doesn't drop as much as it traditionally does.

The point about the torque was that spinning the tires on dry pavement off the line means you have more low end torque than you can actually use. A 450hp 5.5 would be lower geared than the 6.2, but with the same power in the high rpm range it would improve acceleration in lower gears. They could keep the gears the same and just reduce the torque delivered to the wheels, reduce spinning the tires, and keep the top end acceleration.

You do bring up a good point about being able to run in 4 cylinder mode more often. I still don't think it's very clear cut how much that affects fuel economy though, because half of 5.5L is still over 2.7L. Even though they have monstrously tall gearing, and taking into account the fact that the OEM would want to run in 4 cylinder mode *less* of the time for emissions reduction, 2.7L is still quite a bit of displacement to work with so cruising at slightly supralegal speeds in 4 cylinder mode should still be possible. Admittedly, the OEM doesn't want too much load in 4 cylinder mode because even though that's better for fuel economy, it would be a little worse for emissions and those are tougher to meet, so they probably have 8 cylinders kick in when they need ~35% max torque, which is probably a significant decrease in efficiency from running in 4 cylinder mode, but I would expect that 45% load on 8 cylinders is not any worse than 90% load on 4 cylinders because there are still 8 cylinders being dragged along, and 90% is typically past the peak efficiency point.

You have to remember that with cylinder deactivation, you gain efficiency from pumping loss reduction and a higher combustion temperature, but friction is not improved upon at all (probably made even worse), and friction is the primary culprit for poor efficiency at low load.

[Draco-REX]

Originally Posted by serialk11r

Uh, I'll believe it when I see it. Clutch drops don't count. Mind you, the BRZ also has a front weight bias and skinny tires, but I still don't believe you if you say that flooring your BRZ on smooth, dry pavement in a straight line makes the tires spin. A 5.7 can be designed to take up less space than a 6.2 if they want it to, the crank can be smaller if the stroke decreases and the block can be smaller either way. The engine was designed from the bottom up supposedly so this is something they could've done.

You said off the line. That means from a a stationary position.

Here: My BRZ spinning 235 Yokohama AD08s from a standing start.

[ame="http://www.youtube.com/watch?v=pajbe6HGMIs"]8/19/12 OVR SOLO Inside Camera - YouTube[/ame]

[Draco-REX]

Originally Posted by Dimman

If the engine was optimized as a smaller displacement, it would be smaller, lighter and rev better. Smaller bore with same wall thickness will be shorter longitudinally. Shorter stroke means the lower crankcase can be shorter/engine can be lower. And since the deck height is based on rod length which is also based on stroke, it too would be less, meaning shorter height and narrower width. Plus less rotating inertia from smaller/lighter internal and reduced stroke diameter.

Not saying it would be a massive amount, but it would be smaller and lighter.

But these engines aren't designed for each specific displacement. A single block is designed to handle as wide of a displacement race as possible to reduce development and production costs. The block casting needs to work for a 5.3L truck motor up to a 7+L ZR1 motor. So in actuality, a 6.2L engine would be a little bit lighter than a 5.7L.

Keep in mind that the LS1 (and now its successor the LT1 in the C7) is a very small and light engine for its displacement compared to its DOHC competitors. It's a pushrod engine so the heads, and hence the cylinder banks, are smaller and lighter than they would be in a DOHC engine. THe LS1 makes such a good swap candidate because it's only 50-80 or so lbs heavier than a cast-iron block 4 cyl. Hell, the RX7 LS1 swaps are so popular because it barely changes the weight distribution of the car, even though the stock rotary engine can fit on an end table.

There's a great picture used in another thread showing the size difference between a LSx engine and a Toyota DOHC V8.

[Dimman]

Originally Posted by Draco-REX

But these engines aren't designed for each specific displacement. A single block is designed to handle as wide of a displacement race as possible to reduce development and production costs. The block casting needs to work for a 5.3L truck motor up to a 7+L ZR1 motor. So in actuality, a 6.2L engine would be a little bit lighter than a 5.7L.

Keep in mind that the LS1 (and now its successor the LT1 in the C7) is a very small and light engine for its displacement compared to its DOHC competitors. It's a pushrod engine so the heads, and hence the cylinder banks, are smaller and lighter than they would be in a DOHC engine. THe LS1 makes such a good swap candidate because it's only 50-80 or so lbs heavier than a cast-iron block 4 cyl. Hell, the RX7 LS1 swaps are so popular because it barely changes the weight distribution of the car, even though the stock rotary engine can fit on an end table.

There's a great picture used in another thread showing the size difference between a LSx engine and a Toyota DOHC V8.

The exercise here is about an optimized 5.X vs the 6.2. If bigger is better, there is no reason for them not to go to 7.0 for the base car. I think GM is approaching the limits on where they can go next with big OHV motors.

And besides cost is hardly an issue with the rest of the car.

As for the RX-7 weight distribution, I don't believe it. I've handled pretty much every single component of both a 12A and 13B. They are ridiculously tiny motors. Eccentric shaft on a 13B (equiv to crank on a real motor) probably weighs as much as an LSx's camshaft.

When we look at the efficiency gains that DOHC engines keep making compared to the OHV, I think GM is running out of displacement options and tech trickery to keep OHV relevant in the future. There is a point where they will not be able to just make bigger motors to suck in air.

Edit: Compact DOHC v8