Walt White Coupe

It's a whole new world out there now and technology is advancing even more rapidly. It's all about power to weight ratio and handling and technology will take care of the mpg's. We may have to wait a while and a C6 isn't a bad car to wait in.

tdogg21

i'm not sure i understand what your saying. are you saying the corvette is going to have to be at 40 mpg to help the gm fleet reach 35? i don't know the numbers, but i'm guessing malibus and cobalts out sell corvettes by a large number. but let's say it's a 2 to 1 advantage. if that's true, wouldn't that mean that if the corvette stayed around 25-30, the other two cars would need to be at 40 to pull the average over 35? that doesn't seem that difficult to me.

VettedCandidate

Jeez, I'm so sick of all the fearmongering here on this site! We had no real change in this standard for 30 yrs and a little change for the FLEET is being greeted as the end of all things Corvette! Quit freakin' out as the Corvette is a real icon and so is GM! We may need to rethink how performance is delivered but performance will be there to be had!

Vette_DD

But 250 hp & 275 hp engines were available in 73 from GM for extra money.

Corvette Black Book says the hp went up in 74, to 195 for the base engine, 250 hp & 270 hp for extra money.

Hp did go down in 75.

Alex1217

Most likely, engine size might go down to C5 levels at 5.7 liters but hp will probably remain at LS3 levels, if not more. The big change will be in overall size and weight. I have a feeling that the C7 will be smaller than the C6 by a few inches. Cabin size will hopefully stay the same. Use of a standard aluminum frame, carbon fiber panels, LED headlights and other weight savings techniques will bring the weight down.

One thing is for certain, 1/4 mile times and track times will improve, otherwise, GM risks losing sales in an increasingly competitive Sports Car market.

gogetum

windmill and/or solar powered

INTELinside

C7 should have this chassis with LS3 engine tweaked for better fuel efficiency (variable cylinder management that uses 4 cylinders in normal driving, 3 for cruising, and all 8 when you stomp it)



Just improve this chassis and GM will have the finest corvette ever produced.

Low Flight

As long as I can still recognize it as a Corvette by it's lines, and it has high performance, then I don't care how they get it. It's more about power to weight and aerodynamcics anyhow, so if they can reduce the weight enough and decrease the CD then less HP is not an issue. That being said, moe is always nice!

Things change though; technology progresses. Remember the '53 had an inline 6 cylinder. I don't necessarily see a V8 as being the be all/end all of Corvette heritage.

Also, the 35MPG CAFE standard applies to the overall fleet. If they make enough cars that make the standard then it really doesn't matter what the Corvette makes. I would hate to see it become subject to a gas guzzler tax though.

FortMorganAl

I'm saying that not only did they raise the required fleet average by more than 25% but they also rolled the larger vehicles than now get less than 20mpg into the mix. Not only will all vehicles have to get more than 25% better mileage but the smaller ones will have to get even more to make up for the bigger ones that don't have a chance of getting anywhere close to 35mpg. The only salvation will be to make the SUVs and large pickups that are currently exempt weigh more than 10,000 pounds to escape the new average requirement. That's how we got Hummers from the last changes in CAFE.

BTW, the current average is barely above 28mpg so the Corvette is an "average" mileage car and will certainly have to be above 35mpg for the new average to be met when a lot of 15-20mpg vehicles are added.

Robs98Z28

If Active Fuel Management, Direct Injection and variable valve timing (like the viper has) where added and you had as many carbon fiber panels on the base vette as you do on the ZR1, I think you could see a corvette with mileage of 30 city and 40 highway.

It would take alot of engineering effort, but I see it as a possibility in the near future.

What do you guys think?

Kappa

It never ceases to amaze me how radical people will go when trying to predict what the next Corvette will have. Eventually, they just refine the same concept they've always used.

I can see them going down in engine size, weight, and power. Won't really matter much if the performance is still there.

harddrivin1le

The Sky/Solstice isn't much lighter than a C6 - despite the fact that it uses a little 4 cylinder.

The turbo versions are making 260 HP now and they run lower 14s @ 98 MPH.

40 more HP (your proposed 300 HP) would perhaps yield high 13s @ 101 MPH. That's hardly fast by today's standards.

harddrivin1le

A Toyota Yaris hatch weighs 2,300 pounds, produces 106 HP from its 1.5 liter 4 cylinder and has Direct Injection and variable valve timing.

It's EPA rated @ 29 city/38 highway.

So...you're dreaming.

brentil

No matter how much I love my Solstice, the platform is not meant for larger engines or for the size needed to really provide the features expected in a Corvette. The amount of engineering required would be fairly extensive, and that's not going to happen since the rumors the current Solstice will be the last Solstice are probably true it seems.

Huh, 10,000 lbs? Hummer H2 weighs 6,600 lbs and a 3/3 ton Suburban 4x4 is 6,500 lbs. Yeah their GVWR is like 8,600 lbs but that's not what's used for calculations. GM is in no way going to make these vehicles weigh 10,000 lbs to try to get passed some sort of regulations. No one would ever buy a vehicle like that, it would make a vehicle with fuel economy values so horrible.

The current CAFE requirement is 27.5 mpg "combined" fuel economy for cars and not the highway value. The 2008 Corvette has a combined fuel economy of 19 mpg which is in no way near average. I'm pretty sure as CAFE goes up we'll also start seeing the definition of Gas Guzzler go up, and GM is going to want to avoid that.

30 city & 40 highway, you'll never see numbers like that on a pure V8 no matter how modern it is or how light the car is. As mentioned it takes a 2300 lbs car with a 1.5L i4 to get values like that. To greatly boost city values you would need to mix a lot of new/exotic technologies to try to reach that. Light/full hybrid system, start/stop technology, HCCI (once it's perfected), DI, VVT, variable compression, etc etc.

This is not going to happen anytime son in the next 5+ years from GM. GM has already killed the high feature V8 program (DI, VVT, DOHC) they were developing for the next generation of Cady's. This was done well over 6 months ago and was officially announced by GM. I'll give you one guess what other canceled car redesign this engine would more than likely have been used in as well. So whatever the C7 is going to use, it's not going to be a high featured V8. My guess is either a tweaked LS3, smaller displacement LS3 variant that's boosted to compensate for it's size, or TT V6.

I run 14.1s 1/4 mile runs in my stock Solstice GXP and I have no idea what I'm doing. Solstice GXP can do the 1/4 mile in the high 13s (we've seen several 13.8s in stock cars). The Stage II kit coming from GM next month (290 HP & 310 lbs-ft) should easily put it in the very low 13s and could do even lower with proper tires and driver. We've got members on our forum pushing 290~300 rwhp just from tuning the ECM that still maintain 23+ mpg city and 32+ mpg highway. Not bad for a little 4 cylinder.

Just an fyi, the Yaris engine does not have DI, it does have "Toyota Direct Ignition" which is Toyota buzzwords for individual coil packs per cylinder. DI injection version would be getting far better power and fuel economy values in relation to other like sized engines.

brentil

We've actually had some long discussions on the possibility of a V6 C7 at the solsticeforum. As I just mentioned GM was developing a high feature V8 that would have been the future Cady and more than likely C7 engine but the project was officially canceled. GM has two main options at this point;

1. Pushrod V8 variants
   1. Evolution of the LS3 as some sort of future version - easiest development of them all, could provide small quick turn around but will provide the least HP/MPG benefits, could be shared across Corvette/Camaro/CTS/G8
   2. Smaller displacement super/turbo pushrod V8 version - could provide more HP and better fuel economy, maintains V8 image, possibly more development time and cost, could be shared across Corvette/Camaro/CTS/G8
2. Twin Turbo V6 VVT and DI - would require the most upfront development but could provide the largest benefit (weight/cost/mpg), could be shared across any of GM's vehicles using a V8/V6 currently greatly lowering costs overall by increasing volume greatly

GM is bleeding money like there's now tomorrow. They just don't have the money to keep throwing at specialty items anymore. They killed the high feature V8 because they knew it just wouldn't be worth it in the long run. After killing that engine they're not going to start development up again of an engine like it again for a very long time.

The thing is I don't see any of them as being downgrades for the Corvette in my opinion at least. I want a car that performs, and I don't need to have a V8 to feel like I have a performance car, but I wont say no to one. I agree a good majority of current Corvette owners would not be happy with a V6 at this time in the Corvette. That's why I think it should be a base engine for the cheapest version, but at the same time still offer a V8 like the LS3 in the Corvette as a slight upper option. Make the TT V6 20+ HP less than whatever V8 is in there at the time. Like a 400HP V6 and a 430HP V8 or higher if they have a better version by then. That way those current Corvette owners who don't care have a choice and anyone out there who what engines is in the Corvette isn't as important as the overall car. I could see the TT engine bringing in a new crowd of people possibly too.

GM has shown prototype TT 3.6L DOHC, VVT, DI in one of the Buick Concept cars producing 400 HP & 400 lbs-ft. Not too bad for a prototype engine shown over a year ago. A setup like this would match a LS3 for overall weight. However a lower displacement V8 based off the LS3/LS7 that's turbo/super would also provide a basis for a lot of power with much improved fuel economy and low design costs. However this will add weight beyond a normal LS3's weight.

robvuk

I'm curious where all you guys ever got the impression that smaller displacement turbo engines get better mileage than equivalent hp pushrod V8's????? Or that they are physically smaller??? Or that they weigh less????? Let me just say right here that you are WRONG! The world is full of perfect examples from Europe and Japan. The only time a small displacement engine gets better mileage is at idle or stop and go traffic. This is easily matched by disabling uneeded cylinders in a V8 which is probably the next step.

humvet

2012 secret prototype - turbine.

gengiskhan

i think is goin to be smaller slightly at about base 3100lbs DOD, 7 speed tranny, maybe an adaptation of the hybrid system used in the the hybrid trucks/suv they have
the tech is ther already and incorporating it with out to many issues is possible
maybe a lower cd of drag all that would improve gas mpg by about 4-5mpg with a slight increse in price

now a 5.3 supercharged motor making 450hp with dod and 7 speed tranny that could happen and get 30 plus on the freeway but its a big leap

CPhelps

I haven't seen any solid numbers for the LLT 3.6L DOHC engine's weight (if anyone has them [fully dressed preferably] I'd be interested to see) so I'm not convinced it is necessarily lighter than an LS-aluminum V8 engine. The DOHC heads would probably have issues fitting under the Corvette hood line as well, as we saw with the ZR1 that GM had to go to great lengths to ensure the LS9 was only minimally larger than the other LS engines in order to fit. Add in associated turbo hardware, and any weight advantage likely disapears.

We don't have a great basis to compare the LLT fuel efficiency wise with the Gen IV V8s, since the vehicles they appear in from GM are quite different, but I'll give it a shot. The new CTS weighs 3874lbs, makes 304hp/273lbft of torque and returns 17/26mpg figures with the LLT 3.6L DOHC DI v6. The slightly lighter (3712lbs) Chevy Impala equipped with the 5.3L LS4 (with AFM/DoD) makes 303hp/323lbft of torque and returns 18/28mpg using a 4-speed auto compared to the Caddy's 6speed. Again, not a perfect comparison since the Chevy is slightly lighter and has 2 less gears, but I think it is one of the best we can make at this time.

The abundance of "low end" V8 torque also makes things like CAGS skip shift possible, while not a hugely popular solution, it did allow GM to circumvent the GG tax on many Corvettes.

Either way, neither engine is going to be getting great mpg when being pushed hard, and I am just skeptical that the TT V6 is the solution to better mileage figures from the Corvette.

ZO6 Fan

And w/ Displacement on demand technology