Can a V8 Sports Car be Fuel Efficient?

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ildd
Google "Automation Game" and give them all your money. It's currently in development.
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On topic: Yes, it's possible. Expensive? Maybe.
 
Some one beat me to it...
The Corvette has been capable of good HWY MPG for years now, I mean, even the C5 could run the interstate getting better mileage than many smaller slower cars.
 
Kent
Some one beat me to it...
The Corvette has been capable of good HWY MPG for years now, I mean, even the C5 could run the interstate getting better mileage than many smaller slower cars.
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Probably because they practically idle at highway speeds in 6th gear.
 
I've already been beaten to the obvious Corvette answer, so I'll post something not quite as obvious.

The SLK55 AMG can get 28mpg on the highway, but lol good luck.

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ND4SPD
Super tall 6th gear helps quite a bit. I can only imagine what a C7 can achieve with a 7 speed and cylinder deactivation.
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Best we can guess, I think, would be applying the cylinder deactivation tech from the 6.2L V8 used in the 2014 trucks to the 2015 models. Those trucks benefitted from about a 10-15% increase in fuel economy with the additional tech. Combine that with the Corvette, and maybe even add something like the new 8-speed automatic, and I think you could easily see EPA ratings for the highway go to somewhere near 30-32 MPG.

...Still makes me wish they'd do a 5.3L Corvette.
 
What's wrong with having a smaller engine? Corvettes in the past have been fitted with rather small engines and others have been downsized. So long as the weight and power stays similar to what it is now, I see no reason why they couldn't benefit from a smaller engine.
 
Because that's not what the Corvette is about. It's not a Mother Earth Hero Car. The point is noise and speed - a big nasty V8 spewing greenhouse gases as it delivers freight-train like performance. I like the look of the current Corvette but I think all these touchscreens and all this everything-by-wire garbage need to go.
 
White & Nerdy
Because that's not what the Corvette is about. It's not a Mother Earth Hero Car. The point is noise and speed - a big nasty V8 spewing greenhouse gases as it delivers freight-train like performance. I like the look of the current Corvette but I think all these touchscreens and all this everything-by-wire garbage need to go.
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Welcome to the future. Buy old cars like me.
 
White & Nerdy
Because that's not what the Corvette is about. It's not a Mother Earth Hero Car. The point is noise and speed - a big nasty V8 spewing greenhouse gases as it delivers freight-train like performance.
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And a 5.3L can't do that? Because I have news for you. There are 4.5L V8's out there that will 🤬 all over that 6.2L currently in it. Modern technology can EASILY coax that kind of power out of the 5.3L. Why they haven't done it is simple. Marketing. People like big numbers because big numbers = bragging rights.

White & Nerdy
I like the look of the current Corvette but I think all these touchscreens and all this everything-by-wire garbage need to go.
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This I fully agree with you with.
 
Don't get me wrong I love a 13+ liter big block and I'd love to stuff one in everything but displacement isn't the answer to everything. Even I know that.
 
White & Nerdy
Whatever that 5.3 can do, the 6.2 can probably do better.
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I'm not in concern about the comparision over old and new V8's, nor am I in concern over the size of a V8 engine. I'm just wondering if it's possible to make a V8 sports car that can give an ample amount of performance while conserving gas.

Anyway, the C7 Corvette Stingray and the SLK55 AMG are ones that are able to pull off high MPG figures for a V8 sports car, as I have heard of so far. Are there any other V8 sports cars (C7 & SLK55 AMG can if the driver doesn't have a leadfoot all the time) that can pull off 30+ MPG on the highway?
 
Well, I know my V6 sports truck can't be fuel efficient.

12 MPG FTW!
 
Tyger
Ohhh OK not great then, though that's made me wonder about the Rover/Buick V8...I know the MG wasn't too economical but what about the numerous TVRs that used it, or even the Rover SD1? Of course I could be less of a lazy ass and look all this up myself :)
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The trouble there isn't the engine necessarily but the way those engines were set up. Plenty of old British sports cars given American V8s were pretty lightweight given the engines' usual homes, but a big chuntering 1970s V8 on carbs will never be particularly economical.

The newer ones are genuinely impressive. All the tech involved is delivering engines that are faster, more driveable and more economical than their older counterparts. So you can buy a new Corvette or whatever and mix it with supercars on the race track, and then stick it on the highway home and get decent economy at a cruise. Pretty useful combo.

To go back to the thread title though, as others have said - "fuel efficiency" is relative. For someone used to doing 15 mpg, a 30 mpg car is ridiculously efficient. For someone used to 50 mpg, not so much. Will regular V8s hit the latter? Not for some time, I suspect. Possibly never, without hybridization. Is it impressive they're hitting mpg in the 30s though? Yes, considering it wasn't that long ago they were using twice the fuel over a given distance.
 
I really think those fat pigs of v8s from the 70s would have been more fuel efficient without all that emissions garbage.
 
Slash
I really think those fat pigs of v8s from the 70s would have been more fuel efficient without all that emissions garbage.
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Possibly so, but it's worth pointing out that the fat pigs from the 60s or 50s were hardly sipping fuel either. The "fat pig" part was probably more of a problem (since cars really did get heavy in the 70s) but otherwise those sort of engines are just inherently inefficient. Which is fine, because that's not what they were designed for.
 
The current M6 can get a realistic (I.e. Not stupid test conditions that exaggerate the figures) 20mpg mixed so imagine it could get. 25 maybe 30 on long runs.
 
Though with modern gearing, the 1960s ones at least can do much better than originally. I recall more than one first generation Camaro with T56 in it and 20+ claims.
 
Tornado
Though with modern gearing, the 1960s ones at least can do much better than originally. I recall more than one first generation Camaro with T56 in it and 20+ claims.
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Yeah, gearing plays a big part. Turning over at little over idle thanks to gearing, and being able to pull at that speed thanks to low-down torque, is what makes some of the current V8s quite frugal for their type.
 
homeforsummer
Possibly so, but it's worth pointing out that the fat pigs from the 60s or 50s were hardly sipping fuel either. The "fat pig" part was probably more of a problem (since cars really did get heavy in the 70s) but otherwise those sort of engines are just inherently inefficient. Which is fine, because that's not what they were designed for.
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True but I think that was more so due to the fact that stock parts on them absolutely sucked as far as flow go, hence why aftermarket is popular (for fuel economy and power).

Tornado
Though with modern gearing, the 1960s ones at least can do much better than originally. I recall more than one first generation Camaro with T56 in it and 20+ claims.
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I agree with this. Those old cars were geared for decent acceleration (depending on the car) and not fuel economy as so many cars are now, though some cars with smaller engines had "highway" gears n the axle. Considering most new muscle cars at best come with a 3.55 rear axle ratio and if you are lucky a 3.73, that was considered low to mid end back in the days when cars rolled out of the factory with up to 4.56 gears in some applications while others were in the mid 2's for 6 cylinder variants. That still wasn't enough though when everything was stuck with high geared 3 and 4 speeds. This is one of those tricks to get those claimed 25-30mpg out of small blocks in those big Bronco's I previously mentioned (but most are indeed built for economy). A cleaner burning and freer breathing engine with fuel injection and low, LOW gearing and 6 gear transmissions is what did it. You have to remember, with those high gears out back, 65mph you were turning almost 3,000rpm, and sometimes more.

Today, with that 6th+ gear, you can almost make it back down to idle. It wasn't uncommon for 4 cylinder carbureted cars with highway gears of the 70s to actually get 30mpg. In fact, the Pinto and Mustang II with the 4 cylinder applications did quite well on gas, for the time. I've read that they averaged about 30 and some as good as 34. So I do believe that with the right gearing those old pigs of V8's could actually do quite decent. I mean hell, the manual 2.3L in the first gen Fox Body was rated 40mpg highway and consistently got 33mpg combined. That was in 1979.
 
Slash
I agree with this. Those old cars were geared for decent acceleration (depending on the car) and not fuel economy as so many cars are now, though some cars with smaller engines had "highway" gears n the axle.
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That's oversimplifying it a little - it's worth pointing out that modern performance cars are typically quicker than old ones regardless of gearing, and that fuel economy is a byproduct of inherently more efficient engines than cars used to have. Tighter tolerances, better fueling, more efficient intake designs and of course more gears in the transmission in the first place - several for acceleration and several as overdrives, effectively.

The average econobox these days has gearing biased towards efficiency, but then that's arguably how it should be.

I suppose it's also worth noting that the pursuit of efficiency is a lot more refined than it used to be. As you noted, in the 1970s they just slapped emissions controls on everything, strangling the engines in order to reduce emissions. Now, you can make an engine continually more powerful yet improve its fuel efficiency too.

To spin the "efficiency" thing another way, efficiency in terms of fuel used goes hand-in-hand with performance. In F1 at the moment the car with the most powerful powertrain (the Mercedes) also uses the least fuel over the course of a race... speed and efficiency are not mutually exclusive.
 

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