Just had a thought about CAFE

[Camino LS6]

With many four-cylinder cars now making really big power, and V6s having mpg like V8s without the power, couldn't the automakers dispense with many of the V6 applications?

Might that not create an efficiency situation that would allow for V8 cars to fit more easily under the new CAFE regs while keeping the formerly V6-powered cars at similar power levels while dramatically increasing the CAFE numbers?

Just a thought.

[Intrepidation]

Thing is, V6 are getting to the point where they make power of V8's. For example: the 3.6 DI in the CTS makes more power than the V8 in the Lucerne as I recall.

Some of Ford's EconBoost models are claimed to make like 400 horsepower.

[Camino LS6]

Thing is, V6 are getting to the point where they make power of V8's. For example: the 3.6 DI in the CTS makes more power than the V8 in the Lucerne as I recall.

Some of Ford's EconBoost models are claimed to make like 400 horsepower.

Some do, true.

But a vast number are just engines which are too heavy for their application in cars that might even perform better with a hot 4.

In other words, in many cars a V6 is just a complete waste.

I'm not saying that all V6s should go away, just that their application make more sense. V6s make up a HUGE proportion of all cars sold here, I think that need not be in a majority of cases.

[Camino LS6]

Think of it this way:

Let's say that 7 million cars/trucks are built each year with a V6.

What if a 4 could do the job as well or better in 3 million of those?

See my thinking?

[Satty]

Then wouldn't it also make sense to kill the V8 and use hot V6s in performance models?

[Camino LS6]

I could be wrong, but it seems to me that a 4cyl and V6 with the same power levels differ far more in MPG than a V6 and a V8 with the same power would.

I just see huge gains to be made with this idea.

[Camino LS6]

Then wouldn't it also make sense to kill the V8 and use hot V6s in performance models?

No, apples and oranges, for two reasons.

1. The V6s that make V8 power don't have much , if any MPG advantage over the V8.

2. So few V8s are used outside of truck-based vehicles that there is little to gain there.

[Camino LS6]

We'd need real numbers to flesh this out, but I feel confident that the idea is sound.

[Sixty8panther]

Camino: you might remember I've said exactly that.

baby V8, big V8 and a couple 4-cylinders.

DF: NO V6, no matter how powerful.... Buick 3800 & Nissan's VQ included,

will ever be an acceptable substitute for a V8, no matter how small.

V6s are obsolete.

[Camino LS6]

I wouldn't call the V6 obsolete, but it has always been a compromised powerplant.

Right now, it is the heart of the market, and what better place to look for CAFE gains?

[z28luvr01]

Something to consider now is that, at least in the case of GM, new technologies are being phased in gradually. DI, for example, helps make a turbo 2.0L 4cyl every bit as good as a non-DI 3.6L V6, and a DI 3.6L V6 is every bit as good as a 5.7L V8 from a few years ago. I would really love to see a production V8 fitted with DI, only instead of having the V8s make more power, they'd make the same power but shrink in displacement to increase fuel economy. Couple that with a lighter weight car, and you have a faster, more efficient vehicle.

[Sixty8panther]

Bottom line:

there is NO need to talk of limiting production #s of cars with V8s.

[Camino LS6]

Something to consider now is that, at least in the case of GM, new technologies are being phased in gradually. DI, for example, helps make a turbo 2.0L 4cyl every bit as good as a non-DI 3.6L V6, and a DI 3.6L V6 is every bit as good as a 5.7L V8 from a few years ago. I would really love to see a production V8 fitted with DI, only instead of having the V8s make more power, they'd make the same power but shrink in displacement to increase fuel economy. Couple that with a lighter weight car, and you have a faster, more efficient vehicle.

Z, you should check out my comments in the most recent Camaro thread. :AH-HA_wink:

http://www.cheersandgears.com/forums/index...=25809&st=0

[loki]

DF: NO V6, no matter how powerful.... Buick 3800 & Nissan's VQ included,

will ever be an acceptable substitute for a V8, no matter how small.

V6s are obsolete.

ugh..just update the GNXs!!! lol

if my monte could have a 5speed with a 2.4 / 2.3DI 4 cylinder i'd live with that. the only thing i love about my V6 is the more lower torque, NA 4's just don't putt around at 1500rpm well. since my 3.1 has ~160hp and 170ftlbs. when the 2.4L has more horses and practically the same torque.

i know i've said it before, but i think a small 3.x L v6 with 3valves and DI would be a great compromise of MPG and good power...maybe even fit in a delta II?

[Camino LS6]

ugh..just update the GNXs!!! lol

if my monte could have a 5speed with a 2.4 / 2.3DI 4 cylinder i'd live with that. the only thing i love about my V6 is the more lower torque, NA 4's just don't putt around at 1500rpm well. since my 3.1 has ~160hp and 170ftlbs. when the 2.4L has more horses and practically the same torque.

i know i've said it before, but i think a small 3.x L v6 with 3valves and DI would be a great compromise of MPG and good power...maybe even fit in a delta II?

The car would have better manners overall with a lighter 4 cyl. up front.

[pow]

Six-cylinder engines still make sense in many applications... I mean, looking at our driveway, we have a 4400-lb minivan (Odyssey) with a 3.5L V6. Turbocharged four-cylinders tend to guzzle in heavy cars, so that won't work, and a V8 would be too powerful and even thirstier. There isn't a single non-hybrid V8, car or truck, that gets more than 16 mpg EPA city.

And the 5-series... the choice of a six-cylinder also makes sense. BMW's twin-turbo 3.0L performs as well as their 4.8L V8, yet it gets several more MPGs.

Edited September 30, 2008 by empowah

[pow]

By the way, with all the gloom and doom over CAFE... the regulations really aren't as tough as they seem.

From another thread...

An average of 35 mpg seems impossible if you use EPA consumer mpg testing methods. Fortunately CAFE uses pre-2008 numbers, and unadjusted numbers at that. For example, a Prius is rated 48/45 mpg (2008+) and 60/51 mpg (pre-2008), but for CAFE purposes, it's 66/62 mpg. The E85 1.2mpg credit helps as well.

The 2009 Malibu mild-hybrid gets 26/34 mpg, but for CAFE purposes, its average is 40 mpg.

CAFE is now industry-wide mpg, like in Europe, meaning manufacturers that sell larger vehicles have a lower target.

For instance, GM passenger cars will have to average 34.7 mpg by 2015, whereas VW passenger cars will have to average 39.6 mpg.

GM trucks will have to average 27.4 mpg by 2015, whereas Mercedes trucks will have to average 31.9 mpg.

Here's the mpg (CAFE) for some existing GM light trucks...

VUE Hybrid (BAS): 37 mpg

Silverado Hybrid: 27 mpg

Traverse: 26 mpg

Silverado XFE: 23 mpg

[2015 target: 27.4 mpg]

CAFE mpg of some existing GM cars...

Malibu/AURA Hybrid: 40 mpg

Cobalt XFE: 40 mpg

Vibe: 38 mpg

CTS: 29 mpg

[2015 target: 34.7 mpg]

Edited September 30, 2008 by empowah

[Sixty8panther]

automakers refuse to adapt the I6 for use in the 21st century... Suzuki aside,

it's a terrible waste that the Atlas motors are being killed off and were never

utilized beyond a couple trucks.... inline/slant SIXES beat the crap out of 99%

of V6s and so that right there turns me off to most of today's sixes.

Edited September 30, 2008 by Sixty8panther

[Sixty8panther]

And the 5-series... the choice of a six-cylinder also makes sense. BMW's twin-turbo 3.0L performs as well as their 4.8L V8, yet it gets several more MPGs.

you have your anti-V8 stigmate and it makes you an ANTI-enthusiast.

That's BMW...GM's pushrod V8s wipe the floor with almost any stupid 4-cam

V8 in terms of MPG while retaining hp & torque. I've said it a million times, a

am-in-block, pushrod, OHV motor with ONE camshaft is a lot less parasitic

at low rpm and REAL world applications than a BIGGER, HEAVIER motor with

FOUR camshafts and twice the valves!

Bring down the displacement and external size (by extension weight) of GM's

Ls-series and you have a force to be reckoned with!

[Camino LS6]

I never said that the V6 should be abandoned, only that its use be tempered.

I know that mileage is calculated differently for CAFE purposes, but the requirements are progressive going forward and more headroom underneath the limits can only be a good thing.

My premise here is that so many cars are equipped with relatively thirsty v6s that offer little or no benefit to their owners. If they were to be replaced with a very good 4cyl, no apprecciable loss would appear. Further, there are so many such cars on the market that huge reductions in consumption could be realized. Given the nature of such cars and their buyers, I doubt that many would notice the change except when they fill up.

A large enough trend in this direction could then allow the manufacturers to broaden the range of their powerplant offerings in cars that are best optimized with a V6 or V8.

More choice, less fuel consumption, and all the power we want.

Everyone wins.

[PurdueGuy]

I can't help but feel that the main reason behind this argument is just a psychological attachment to the number 8 as it relates to cylinders. Seems like it all starts with "I want a V8, how can I justify that?" rather than "considering current technology and needs, what is justified?" I'm not against 8's, but I just see this whole argument as a defensive move to displace the threat away from the 8 toward anything else, in this case the 6cyl.

[Camino LS6]

I can't help but feel that the main reason behind this argument is just a psychological attachment to the number 8 as it relates to cylinders. Seems like it all starts with "I want a V8, how can I justify that?" rather than "considering current technology and needs, what is justified?" I'm not against 8's, but I just see this whole argument as a defensive move to displace the threat away from the 8 toward anything else, in this case the 6cyl.

Not so.

The V6 is currently the fat middle of the market, so any meaningful progress on CAFE needs to take place there. Even if you were to eliminate the V8 from all cars, the effect would be minimal - so the V8 is not a valid place to look for CAFE gains at this point.

[PurdueGuy]

There will certainly need to be action taken regarding 6's. I would expect a great number of them to be replaced by large displacement and/or turbo 4's. Of course, some vehicles will need more power than that, so not everything can become a 4. At that point, the question becomes whether the remaining needs are better filled by 6's, 8's, or some of both.

That's where there seem to be the two theories:

a) 6's can put out the power that 8's did not long ago easily & reliably, so why bother with 8's

b) 8's can put out the power of 6's and more

From there, a logical look at the situation would look at the advantages/disadvantages of both:

6's) should be able to get marginally better fuel economy, lighter, fewer parts, should be cheaper to build & maintain

8's) more potential hp/torque, easier to design to be naturally balanced

So... how much power do vehicles need? If the needed power of trucks means a need for 8's, then maybe GM SHOULD look into polarizing their engine lineup into 4's and 8's, make the 8's standard in full size trucks, and sometimes slip 8's into large & enthusiast focused cars. If 6's can easily give all the power that GM's trucks need (keep in mind, they're selling/have sold their commercial truck biz), then it might be more logical (if less appealing to enthusiasts) for GM to focus on 4's and 6's?

I personally like the idea of owning an 8cyl sports car, but I'm trying to approach this from a logical standpoint.

[Camino LS6]

There will certainly need to be action taken regarding 6's. I would expect a great number of them to be replaced by large displacement and/or turbo 4's. Of course, some vehicles will need more power than that, so not everything can become a 4. At that point, the question becomes whether the remaining needs are better filled by 6's, 8's, or some of both.

That's where there seem to be the two theories:

a) 6's can put out the power that 8's did not long ago easily & reliably, so why bother with 8's

b) 8's can put out the power of 6's and more

From there, a logical look at the situation would look at the advantages/disadvantages of both:

6's) should be able to get marginally better fuel economy, lighter, fewer parts, should be cheaper to build & maintain

8's) more potential hp/torque, easier to design to be naturally balanced

So... how much power do vehicles need? If the needed power of trucks means a need for 8's, then maybe GM SHOULD look into polarizing their engine lineup into 4's and 8's, make the 8's standard in full size trucks, and sometimes slip 8's into large & enthusiast focused cars. If 6's can easily give all the power that GM's trucks need (keep in mind, they're selling/have sold their commercial truck biz), then it might be more logical (if less appealing to enthusiasts) for GM to focus on 4's and 6's?

I personally like the idea of owning an 8cyl sports car, but I'm trying to approach this from a logical standpoint.

Trucks needing 8s is a given, beyond the half tons no 6 will cut it.

That said, a complete polarizing of 4s and 8s can't cover everything. Sixes will still be needed in certain applications.

But I think those applications are far fewer than in the recent past.

[loki]

The car would have better manners overall with a lighter 4 cyl. up front.

ok, but some people will never go to 4's...i was saying that a small 3L v6 would be great for people that want NA power above ~200 hp but not want more ..like how much the 3.6 puts out.

i know this thread isn't about eliminating the 6's but seeing what is possible... could the same "argument" be said of europe, sorta... 3's and 5's, why use 4s so much? or go back about 10 years and why not 6's and 12's instead of 8's?

i'd love a V8, something around 4L - 5L but a v6 is just what i'm used to and does very well. i don't really have experience driving 4's other than a ~90? corrola 5 speed (carbed).... that hardly counts.

[Camino LS6]

ok, but some people will never go to 4's...i was saying that a small 3L v6 would be great for people that want NA power above ~200 hp but not want more ..like how much the 3.6 puts out.

i know this thread isn't about eliminating the 6's but seeing what is possible... could the same "argument" be said of europe, sorta... 3's and 5's, why use 4s so much? or go back about 10 years and why not 6's and 12's instead of 8's?

i'd love a V8, something around 4L - 5L but a v6 is just what i'm used to and does very well. i don't really have experience driving 4's other than a ~90? corrola 5 speed (carbed).... that hardly counts.

It's all about optimizing each package with the proper powerplant, it is just that V6s are applied wholesale and sloppy. So it's time to cull the herd a bit.

[loki]

It's all about optimizing each package with the proper powerplant, it is just that V6s are applied wholesale and sloppy. So it's time to cull the herd a bit.

couldn't you say the same about v8s in some areas? not that that will continue much if things keep going the way they are.

is the widespread v6's a sign that there are too many similar models on the market?

[Camino LS6]

couldn't you say the same about v8s in some areas? not that that will continue much if things keep going the way they are.

is the widespread v6's a sign that there are too many similar models on the market?

V8s are so few and far between that I don't think a problem exists there at all. But you have a point about the V6 being a sign that too many similar models are on the market generally.

Even so, I think that way too many cars offer a v6 that should not, and that too many V6 cars are built when an option over a 4.

For years, people yearned for at least a 6 (perhaps because they missed having an 8 ). The manufacturers responded by offering a V6 in cars that had previously only offered a 4. Then they promoted the v6-equipped cars heavily. The dealers responded by trying to stock more V6 cars and less with a 4. In the process, everyone got a bit lazy and we ended-up with a V6 in damn near everything. So, what I'm saying is that a more critical eye on which cars to equip with a V6 is in order going forward.