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Link Posted: 8/21/2012 5:58:04 PM EST
Originally Posted By SnoopisTDI:

Originally Posted By Banjaxed:
Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.


You're looking for energy from nothing. Running those electronic accessories would take a bigger alternator to power them which would create more drag and negate any gains.

I think BMW does that in Europe with their "efficient dynamics" diesels.


I'll have to look that up but essentially if what he said worked you would see a lot of electric driven superchargers.
Link Posted: 8/21/2012 5:58:17 PM EST
Efficiency in the engine will only carry you so far. Highway MPG is hugely a factor of aerodynamics and rolling resistance.

So design sleek trucks with skinny, high-pressure tires with little tread to them, and combine that with the ultra-efficient engines. Then you'll get a 30MPG truck that nobody will want to buy because they won't look manly.

You can have your cake, or you can eat it. But not both.

Link Posted: 8/21/2012 6:01:38 PM EST
Originally Posted By GlutealCleft:
Efficiency in the engine will only carry you so far. Highway MPG is hugely a factor of aerodynamics and rolling resistance.

So design sleek trucks with skinny, high-pressure tires with little tread to them, and combine that with the ultra-efficient engines. Then you'll get a 30MPG truck that nobody will want to buy because they won't look manly.

You can have your cake, or you can eat it. But not both.



More importantly they will be useless as a truck thus negating their purpose. Might as well have a car.
Link Posted: 8/21/2012 6:02:05 PM EST
All the 4 ton diesel truck guys on this website get that easily.

Link Posted: 8/21/2012 6:02:23 PM EST
[Last Edit: 8/21/2012 6:04:24 PM EST by GlutealCleft]
Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.


Car alternators are notoriously, hugely inefficient. Most times, they only convert about 50% of the mechanical energy to electrical.

Plus, at 12V, it's just not feasible. How many HP does it take to run a turbo/blower? Figure about 75 amps for each HP delivered by the motor, so you'd be talking about alternators about 10x the size they are now, and huge, solid copper bus bar to the motors. There's a reason why electrically-driven cars operate at 400+ volts. Even with a seperate, high voltage alternator for the power electronics, you'd need an alternator at least 10x larger than what you have now.
Link Posted: 8/21/2012 6:05:06 PM EST
Originally Posted By flyinreallyhigh:
Originally Posted By NotAFudd:
Originally Posted By hondaciv:
In before the Cummins guys.


Too late I've been cummins all day



hehehe nice. There was a guy on the 4btswaps board that did an F150 swap that was getting IRC ~30mpg, I know that the was a company that was doing wrangler swaps 2/4 door and claiming 30+ mpg.


If you find the LaRue thread where he showed all those pics of his shop, you can see a Wrangler with a Cummins sticker on the door.
Link Posted: 8/21/2012 6:11:00 PM EST

Originally Posted By flyinreallyhigh:
http://www.dieselpowermag.com/tech/general/0708dp_1997_dodge_ram_3500_dualie_cummins/

Yes I'm a cummins guy, my 2500 QC 4x4 just got 25mpg on the trip back from Yellowstone. The linked article is very legit, the really did everything right. The only spots I would see for improvement would be lowering it, not drastically but every little bit does help. Not being a dually with the wide ass end fenders, A proper air dam up front. and they folded in the mirrors but you could easily swap mirrors from a car onto it.


You know that is all fine and good and all, but I always crack up when I read threads like this about MPG on a fullsize because why the hell are you guys so bent on driving them when you aren't actually pulling something? That is their purpose after all. I too am a 5.9L Cummins guy (06 1 ton QC 4x4 dually longbed) that I only own to pull with (also have an 00 7.3 Ford with the same setup). It will do about 17-18 highway bobtailing, 11-13 pulling and that is all I want out of it. I don't actually use them to go get groceries by themselves or anything.

I have more fuel efficient vehicles for just driving around in. But those vehicles don't get used to tow with either.
Link Posted: 8/21/2012 6:16:02 PM EST
[Last Edit: 8/21/2012 6:17:00 PM EST by JustinOK34]
Originally Posted By gomulego:

Originally Posted By flyinreallyhigh:
http://www.dieselpowermag.com/tech/general/0708dp_1997_dodge_ram_3500_dualie_cummins/

Yes I'm a cummins guy, my 2500 QC 4x4 just got 25mpg on the trip back from Yellowstone. The linked article is very legit, the really did everything right. The only spots I would see for improvement would be lowering it, not drastically but every little bit does help. Not being a dually with the wide ass end fenders, A proper air dam up front. and they folded in the mirrors but you could easily swap mirrors from a car onto it.


You know that is all fine and good and all, but I always crack up when I read threads like this about MPG on a fullsize because why the hell are you guys so bent on driving them when you aren't actually pulling something? That is their purpose after all. I too am a 5.9L Cummins guy (06 1 ton QC 4x4 dually longbed) that I only own to pull with (also have an 00 7.3 Ford with the same setup). It will do about 17-18 highway bobtailing, 11-13 pulling and that is all I want out of it. I don't actually use them to go get groceries by themselves or anything.

I have more fuel efficient vehicles for just driving around in. But those vehicles don't get used to tow with either.


You don't "need" an AR-15 just to go to the range to shoot holes in paper. A bb gun would do the same thing.
Link Posted: 8/21/2012 6:18:23 PM EST

Originally Posted By gomulego:

Originally Posted By flyinreallyhigh:
http://www.dieselpowermag.com/tech/general/0708dp_1997_dodge_ram_3500_dualie_cummins/

Yes I'm a cummins guy, my 2500 QC 4x4 just got 25mpg on the trip back from Yellowstone. The linked article is very legit, the really did everything right. The only spots I would see for improvement would be lowering it, not drastically but every little bit does help. Not being a dually with the wide ass end fenders, A proper air dam up front. and they folded in the mirrors but you could easily swap mirrors from a car onto it.


You know that is all fine and good and all, but I always crack up when I read threads like this about MPG on a fullsize because why the hell are you guys so bent on driving them when you aren't actually pulling something? That is their purpose after all. I too am a 5.9L Cummins guy (06 1 ton QC 4x4 dually longbed) that I only own to pull with (also have an 00 7.3 Ford with the same setup). It will do about 17-18 highway bobtailing, 11-13 pulling and that is all I want out of it. I don't actually use them to go get groceries by themselves or anything.

I have more fuel efficient vehicles for just driving around in. But those vehicles don't get used to tow with either.

But you could fit more groceries in the truck, reduce your number of grocery trips, and possibly be more efficient in the truck!
Link Posted: 8/21/2012 6:22:33 PM EST
Originally Posted By memsu:
I think its very possible if the manufacturers offered Diesel engines in 1/2 ton trucks.

Now I don't mean by putting a 500HP Diesel in them like the 3/4 and 1 ton trucks. Something like a 4 or 6 cylinder Diesel with around 300HP and lots of torque.

I could see the lighter 1/2 ton trucks getting close to 30 mpg on the highway with a setup like that. However, here in America we're supposed to embrace the hybrid cars for some reason.




The Germans are offering 6 cylinder diesels in the US.
The BMW (265hp/425lb-ft) gets 19 city/26 hwy.
Mercedes Bluetec (240hp/255lb-ft) gets 20mpg combined.

No 1/2 ton rated truck is going to get 30mpg.
Link Posted: 8/21/2012 6:40:02 PM EST

Originally Posted By SnoopisTDI:

Originally Posted By gomulego:

Originally Posted By flyinreallyhigh:
http://www.dieselpowermag.com/tech/general/0708dp_1997_dodge_ram_3500_dualie_cummins/

Yes I'm a cummins guy, my 2500 QC 4x4 just got 25mpg on the trip back from Yellowstone. The linked article is very legit, the really did everything right. The only spots I would see for improvement would be lowering it, not drastically but every little bit does help. Not being a dually with the wide ass end fenders, A proper air dam up front. and they folded in the mirrors but you could easily swap mirrors from a car onto it.


You know that is all fine and good and all, but I always crack up when I read threads like this about MPG on a fullsize because why the hell are you guys so bent on driving them when you aren't actually pulling something? That is their purpose after all. I too am a 5.9L Cummins guy (06 1 ton QC 4x4 dually longbed) that I only own to pull with (also have an 00 7.3 Ford with the same setup). It will do about 17-18 highway bobtailing, 11-13 pulling and that is all I want out of it. I don't actually use them to go get groceries by themselves or anything.

I have more fuel efficient vehicles for just driving around in. But those vehicles don't get used to tow with either.

But you could fit more groceries in the truck, reduce your number of grocery trips, and possibly be more efficient in the truck!

This is true, but you failed to factor in that these trucks could haul some serious groceries and that would mean that I'd need to build a building just for all the freezers. And freezers and electricty and buildings cost money dontcha know?

Link Posted: 8/21/2012 7:20:12 PM EST
4BT/6BT transplanted into an F150?
Link Posted: 8/21/2012 7:48:21 PM EST
as promised earlier:

Link Posted: 8/21/2012 8:02:53 PM EST
I took my K30 from KCMO to Central Texas on one tank of diesel. That is 20 gallons and 800 miles.



BUT the K30 was being towed . KCMO had diesel at $3.39/gallon so I filled all tanks.
We averaged about 14 MPG.

Weight kills city mileage. Aerodynamic drag kills highway mileage. Trucks have both weight and aerodynamic drag.
Link Posted: 8/21/2012 8:09:47 PM EST

Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.

How much power does the air conditioner take? Bare minimum is 1 HP. Alternators are 80% efficient, electric motors are again about 80% efficient. So your bare minimum 1 HP air conditioner now requires 1.56 HP. Yeah, that is the ticket.

Now, IF the AC compressor could be run at its most efficient speed, say 2000 RPM for a typical Sanden SD7, the increase in the coefficient of performance could be kept above 2.00, meaning slight reduction in power draw but this would require complex control system. Sanden and others noticed this and introduced their variable displacement compressor series (SD7V16) line of compressors so when driven off the standard multi-V serpentine belt, offer all the benefits without the need for a variable frequency electric drive compressor.


Link Posted: 8/21/2012 8:36:09 PM EST
Originally Posted By memsu:
Originally Posted By chipdog4:
I've heard that Nissan will be adopting the new Cummins V-8.
This engine was supposed to go in half ton Dodges.
I would expect this engine to get upper 20's.



Yeah, Nissan is supposed to have a new Titan out for 2014. It was supposed to be a rebadged Dodge Ram, but that cancelled because of the bailout situation in 2008-2009. I'm actually glad that happened, because I love my Nissan Titan and definitely don't want a Dodge. I'd rather Nissan build their own Titan.

From what I'm hearing Nissan is working with Cummins on a department of energy funded project that will last till 2014. Hope something good comes of it.


Engineers are testing the diesel engines in some of the new Nissan vans in Middle TN. The engines will be available in vans and the Titan. They are testing in the vans because it fits and nobody suspects the test engine for the titan in a van. It is not an 8cyl diesel.

Also developed an infinity version of the Leaf. The charging system is nuts, if the gov't approves. It will lead to big leaps in battery charging tech.


My 4.6 2V reg cab f150 gets 24 MPG highway @ 70. 17 in town.
Link Posted: 8/22/2012 3:48:47 AM EST

Originally Posted By LIINTLICKR:
Originally Posted By skin290:
Originally Posted By Admiral_Crunch:

Originally Posted By LIINTLICKR:

I would love a Taco, but I'm not sure my 6'2" frame would appreciate it.

I'm 6'2", and I love my Tacoma. The '05s and up are bigger than the last gen.


I see this all the time, 6'2"? Have you even tried to fit in one? C'mon, that isn't that tall ––MOST cars actually do fit you. (I am 6' and drive a civic with no problem)––my friend is 6'8" and has no problem (surviving) with an s-10.


I'm also not a skinny guy. But I'm going to test drive one this week.

I look like a former linebacker who's let himself go. You should be fine.
Link Posted: 8/22/2012 4:14:08 AM EST
Originally Posted By gomulego:
You know that is all fine and good and all, but I always crack up when I read threads like this about MPG on a fullsize because why the hell are you guys so bent on driving them when you aren't actually pulling something? That is their purpose after all. I too am a 5.9L Cummins guy (06 1 ton QC 4x4 dually longbed) that I only own to pull with (also have an 00 7.3 Ford with the same setup). It will do about 17-18 highway bobtailing, 11-13 pulling and that is all I want out of it. I don't actually use them to go get groceries by themselves or anything.

I have more fuel efficient vehicles for just driving around in. But those vehicles don't get used to tow with either.


For some people, owning a second car is not cost-effective, so they look for a truck with the best fuel mileage. By the time I buy another car, even just a beater, and pay registration and insurance all year long, I can put a lot of gas in my truck. I'm much better off DDing my full size pickup and it makes sense to find one that's fuel efficient, relative to other similar trucks.
Link Posted: 8/22/2012 5:23:10 AM EST

Originally Posted By Keith_J:

Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.

How much power does the air conditioner take? Bare minimum is 1 HP. Alternators are 80% efficient, electric motors are again about 80% efficient. So your bare minimum 1 HP air conditioner now requires 1.56 HP. Yeah, that is the ticket.

Now, IF the AC compressor could be run at its most efficient speed, say 2000 RPM for a typical Sanden SD7, the increase in the coefficient of performance could be kept above 2.00, meaning slight reduction in power draw but this would require complex control system. Sanden and others noticed this and introduced their variable displacement compressor series (SD7V16) line of compressors so when driven off the standard multi-V serpentine belt, offer all the benefits without the need for a variable frequency electric drive compressor.



The Prius gets away with it because it runs the electric AC compressor off the traction battery, not the 12 volt system. 200 volts/6.5 Ah

Other vehicles would have to have a similar setup to make it work...

Link Posted: 8/22/2012 5:50:49 AM EST
Originally Posted By Hamel:

Originally Posted By memsu:
Originally Posted By brian4wd:
Originally Posted By memsu:
I think its very possible if the manufacturers offered Diesel engines in 1/2 ton trucks.

Now I don't mean by putting a 500HP Diesel in them like the 3/4 and 1 ton trucks. Something like a 4 or 6 cylinder Diesel with around 300HP and lots of torque.

I could see the lighter 1/2 ton trucks getting close to 30 mpg on the highway with a setup like that. However, here in America we're supposed to embrace the hybrid cars for some reason.

I think very soon we'll start seeing more Diesel cars and trucks in the states, because the European emissions standard will be close to what the EPA has already set for us.

EDIT: Think about this.

15 mpg average for a gasoline V8 engine
28 mpg average for a Diesel engine

Current Gas Prices in my Area
87 Octane Gas = $3.44
Diesel Fuel = $3.90

Extra $$ for Diesel option = $3000

Say you drive 15K a year.

15K/15mpg = 1000 gallons of gasoline. So, that's $3,440 a year.
15K/28mpg = 535 gallons of Diesel. So, that's $2087 a year.

That's a difference of $1353 a year. So, it would take about 2.95 years to pay for the Diesel option on a 1/2 ton truck.

Well worth it in my opinion. That is of course if we were ever offered that option from any 1/2 ton truck.


Current diesel upgrade cost on 3/4 ton trucks is closer to $7,000 IIRC - don't have any good reason to believe it would be cut in half on half-ton trucks.

Friend had a mid 80's 2wd GM 1/2 ton with the 6.2 NA diesel - I think it got 25mpg on the highway unloaded at a steady 60mph. Not exactly the way people are going to drive on a regular basis.

Brian


I think the demand would be great enough to push down the price of the Diesel upgrade. Plus a lot of manufacturers already have Diesels over in Europe. When the European emissions standards come closer to the EPA standard I think it would become more cost effective. This way they don't have to develop one Diesel for the US and one for Europe. The Diesel option on Mercedes ML350 is only $1000. Mercedes and VW are really serious about having Diesels in the US.

Diesels are perfect for 1/2 ton trucks, and with the new fuel economy regulations they are going to have to find ways to get 1/2 ton fuel economy up. One of the easiest ways will be to have Diesel engines. That alone is worth around a 30% improvement in fuel economy.

Are there any diesel hybrids over in Europe or anywhere else for passenger cars and trucks or is the hybrid car movement more of an American thing?


Peugeot plans to come out with a diesel electric hybrid that has the potential to get 65 mpg using the European fuel economy test. It's a midsized sedan. Now currently diesel electric cars are expensive, because you're paying for the diesel and the hybrid technology. For the short term use I think diesel is the way to go.

The main issue I have with hybrids is they are carrying all the weight of the batteries at HWY speeds. Yeah, they get great mpgs in the city, but in the US lots of people have to travel on the highways to get to work. The VW Passat with the diesel is rated at 43 mpg on the hwy. That's not too far away from the Toyota Prius, and the Passat is a full sized car. So, in this case the VW is nearly 90% as fuel efficent on the hwy as a Toyota Prius (48 mpg hwy). Hybrids have their place for some people, but definitely not everyone in the US. The VW Passat can do 90% of what the Prius can do and not have the complications of a Hybrid powertrain.
Link Posted: 8/22/2012 5:55:31 AM EST
I think one reason we don't have many 1/2 ton diesels is it would take away sales of the 3/4 and 1 ton trucks from the Big 3. Those trucks are huge money makers for them and if people had a diesel option in the 1/2 ton they would buy it instead of the 3/4 or 1 ton truck.
Link Posted: 8/22/2012 6:17:36 AM EST

Originally Posted By imq707s:
Originally Posted By alc1343:
A regular cab, base model Ford F150 with an Ecoboost and 3.15's would probably get close to 25 mpg on the highway, maybe more with a tune.

You could probably pick one up for around 25K or less.


I know a guy with a new Ecoboost....and he gets around 20 on the highway.....with a tail wind.
Supercrew? 4x4? Gears? That all makes a huge difference.

Link Posted: 8/22/2012 6:20:16 AM EST
[Last Edit: 8/22/2012 6:22:50 AM EST by alc1343]

Originally Posted By Banjaxed:
Originally Posted By alc1343:
A regular cab, base model Ford F150 with an Ecoboost and 3.15's would probably get close to 25 mpg on the highway, maybe more with a tune.

You could probably pick one up for around 25K or less.


Ecoboost is not available in regular cabs. Even then it still will not get 30mpg. A 2wd extended cab which is a marginal weight increase over a regular cab will only get 24mpg.
It is, in a long bed configuration, I believe.

Link Posted: 8/22/2012 6:27:27 AM EST
Originally Posted By alc1343:

Originally Posted By Banjaxed:
Originally Posted By alc1343:
A regular cab, base model Ford F150 with an Ecoboost and 3.15's would probably get close to 25 mpg on the highway, maybe more with a tune.

You could probably pick one up for around 25K or less.


Ecoboost is not available in regular cabs. Even then it still will not get 30mpg. A 2wd extended cab which is a marginal weight increase over a regular cab will only get 24mpg.
It is, in a long bed configuration, I believe.



You're right. I looked it up again. In regular cab it is only available with an 8' bed.
Link Posted: 8/22/2012 6:28:20 AM EST
Link Posted: 8/22/2012 7:02:05 AM EST

Originally Posted By SouthEndXGF:
as promised earlier:

http://i856.photobucket.com/albums/ab122/southendxgf/13d03665.jpg

If you had that tuned, who did it?

My new eco supercrew 4wd is nothing close to that. Around 17.5 mixed being easy on the throttle and running 89 oct.


Link Posted: 8/22/2012 7:13:18 AM EST
Originally Posted By BrandonB:

Originally Posted By SouthEndXGF:
as promised earlier:

http://i856.photobucket.com/albums/ab122/southendxgf/13d03665.jpg

If you had that tuned, who did it?

My new eco supercrew 4wd is nothing close to that. Around 17.5 mixed being easy on the throttle and running 89 oct.




It's an instant number - it could have been reading 12mpg a few seconds later. I know if I'm rolling along in my VW and seeing a steady 30mpg, even the slightest incline can knock it into the teens or put it up in the 40s.

That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.
Link Posted: 8/22/2012 7:17:26 AM EST
Originally Posted By SnoopisTDI:
Originally Posted By BrandonB:

Originally Posted By SouthEndXGF:
as promised earlier:

http://i856.photobucket.com/albums/ab122/southendxgf/13d03665.jpg

If you had that tuned, who did it?

My new eco supercrew 4wd is nothing close to that. Around 17.5 mixed being easy on the throttle and running 89 oct.




It's an instant number - it could have been reading 12mpg a few seconds later. I know if I'm rolling along in my VW and seeing a steady 30mpg, even the slightest incline can knock it into the teens or put it up in the 40s.

That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.


In the picture SouthEndXGF posted, it shows average MPG of 25.2. The instant is somewhere north of 30.
Link Posted: 8/22/2012 7:41:30 AM EST
Originally Posted By TinLeg:
Originally Posted By SnoopisTDI:
Originally Posted By BrandonB:

Originally Posted By SouthEndXGF:
as promised earlier:

http://i856.photobucket.com/albums/ab122/southendxgf/13d03665.jpg

If you had that tuned, who did it?

My new eco supercrew 4wd is nothing close to that. Around 17.5 mixed being easy on the throttle and running 89 oct.




It's an instant number - it could have been reading 12mpg a few seconds later. I know if I'm rolling along in my VW and seeing a steady 30mpg, even the slightest incline can knock it into the teens or put it up in the 40s.

That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.


In the picture SouthEndXGF posted, it shows average MPG of 25.2. The instant is somewhere north of 30.


Oops, you're correct!

Is the average over the 1900 miles shown on the odometer, or is that since the last fill-up or... ?
Link Posted: 8/22/2012 8:12:48 AM EST
I think the answer to the original question is no. We have several GMC work trucks the 5.3 2wd gets about 18mpg mixed city use my 4.8 4x4 gets about 19mpg with 33s no tune just a K&N the 2500 4x4 gets maybe 14mpg on a good day. I'd speculate that a 2wd reg cab with the 4.8 would do over 20mpg
Link Posted: 8/22/2012 8:22:07 AM EST
Originally Posted By SnoopisTDI:
That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.[/div]

If a vehicle does not require premium and you run premium....you really are not giving it any help....
Now if it requires premium then that is a different thing.
Link Posted: 8/22/2012 8:25:18 AM EST
[Last Edit: 8/22/2012 8:27:13 AM EST by graysonp]
Originally Posted By SnoopisTDI:
It's an instant number - it could have been reading 12mpg a few seconds later. I know if I'm rolling along in my VW and seeing a steady 30mpg, even the slightest incline can knock it into the teens or put it up in the 40s.


The number in the image is the average MPG since the calculator was reset. It could be calculated based on a few miles, or since the truck was new. Just depends on when/if he reset it. The "instant MPG" text is part of the menu, that's not referring to the number displayed.

Link Posted: 8/22/2012 8:26:12 AM EST
I miss my Diesel Nnissan double cab 32mpg daily 37 freeway my wife's diesel ford Orion got 57mpg
Link Posted: 8/22/2012 8:34:49 AM EST
Originally Posted By Visable-assassin:
Originally Posted By SnoopisTDI:
That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.[/div]

If a vehicle does not require premium and you run premium....you really are not giving it any help....
Now if it requires premium then that is a different thing.


You are correct. So many people believe that running premium in a vehicle that does not require it gives them a performance gain. Higher octane gasoline enables the fuel to withstand higher combustion pressures before it reahes a stage of igniting before spark is added.
The fuel itself does not ad performance, it's the compression ratio of the engine that determines that.

As for the full size truck issue discussed, a 2004-2009 Duramax 2500HD can yield 30+ mpg regularly if it is kept in tune. 2010 models cannot yield the same economy due to DPF and DEF.
EPA killed the economy in the newer units with added emissions regulations.
Link Posted: 8/22/2012 8:34:50 AM EST
I've got a 2009 Dodge Ram 1500 quad cab 4x4, with Hemi 4x8. Meaning when not needed it's only firing 4 cylinders. I'm averaging 17.5. That's about 3/4 hwy and 1/4 city. I live out in the country and drive 50 miles a day round trip to work. I need a pickup for hauling corn and wood. Don't think I'll find anything better than that though.
Link Posted: 8/22/2012 4:07:35 PM EST

Originally Posted By DriftPunch:

Originally Posted By Keith_J:

Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.

How much power does the air conditioner take? Bare minimum is 1 HP. Alternators are 80% efficient, electric motors are again about 80% efficient. So your bare minimum 1 HP air conditioner now requires 1.56 HP. Yeah, that is the ticket.

Now, IF the AC compressor could be run at its most efficient speed, say 2000 RPM for a typical Sanden SD7, the increase in the coefficient of performance could be kept above 2.00, meaning slight reduction in power draw but this would require complex control system. Sanden and others noticed this and introduced their variable displacement compressor series (SD7V16) line of compressors so when driven off the standard multi-V serpentine belt, offer all the benefits without the need for a variable frequency electric drive compressor.



The Prius gets away with it because it runs the electric AC compressor off the traction battery, not the 12 volt system. 200 volts/6.5 Ah

Other vehicles would have to have a similar setup to make it work...


Still takes a LOT of power to run an air conditioner. Sure, the hybrids use traction motor voltage, using a special hermetic sealed compressor with brushless DC permanent magnet motor. This allows precise speed control of the electric motor since it is electronically commutated with a variable frequency drive.

Still, 2.5-5 kW is the norm for maximum output. 746 Watts per horsepower, in a hybrid vehicle, this still must be generated from burning hydrocarbons. 200 volts at 6.5 amps is equal to 1.75 horsepower over a one hour discharge. The 24 volt system in my truck is bigger, 100 amp-hour at 24 volts.
Link Posted: 8/22/2012 4:10:38 PM EST

Originally Posted By memsu:
I think one reason we don't have many 1/2 ton diesels is it would take away sales of the 3/4 and 1 ton trucks from the Big 3. Those trucks are huge money makers for them and if people had a diesel option in the 1/2 ton they would buy it instead of the 3/4 or 1 ton truck.

No, still emissions related. Even though they are all the same now. Direct injection gasoline engines have the SAME thermodynamic efficiency of a diesel, thanks to modern emissions regulations. This is the Ford Eco-Boost and why it gets great mileage.

Link Posted: 8/22/2012 4:40:51 PM EST
Originally Posted By Banjaxed:
Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.


You're looking for energy from nothing. Running those electronic accessories would take a bigger alternator to power them which would create more drag and negate any gains.


Not necessarily. Things like fans and water pumps work efficiently at a certain speed and driving them directly off the engine puts more drag than necessary on the engine.

I read an article a couple years ago about a diesel hot rod shop that built a Cummins and dropped it in a half ton standard cab 2 wd
truck and it would run in the 11s. They drove it across Georgia and averaged over 50mpg. Having driven a few Cummins trucks I have no doubt that they could get some really awesome mileage with a few tweaks and much higher gears.

Link Posted: 8/22/2012 4:56:04 PM EST
Now this is just in my mind, but I have always thought an 03 dodge diesel 2500 or 3500 2wd regular cab long bed with the standard output Cummins and auto tranny would be a good combo to build one of these high mpg trucks.

Throw in a gear splitter/overdrive, 3.55 or 3.73 gears, and lighten it up as much as possible to start with. Then I would go with a more efficient turbo, intake, and exhaust, then go for a different set of injectors. Some mods to the computer and I believe you could hit high 20's.

I base this off my experience with an 03 3500 dodge 4wd with the standard output Cummins and auto tranny with 4.10 gears. The highest I ever got was 23mpg on a road trip, and thats with nothing but an open exhaust. I would routinely get 21 mpg on road trips.

I could only imagine the 2wd would do better, and with doing the right mods to it you should be able to get even better fuel mileage. Might not price inside your range with all of the mods though.
Link Posted: 8/22/2012 5:21:52 PM EST

Originally Posted By Wirebrush:
Originally Posted By Banjaxed:
Originally Posted By pedorrero79:
I think it could exist. IF a lot of the belt-driven accessories were removed from the engine and replace with electronically-driven accessories, I think we'd see a lot better fuel mileage and, possibly, longer lasting engines. That's just my $0.02. It's only an idea though, I've never actually sat down to crunch the numbers so I couldn't really say one way or the other whether it's actually feasible to do that.


You're looking for energy from nothing. Running those electronic accessories would take a bigger alternator to power them which would create more drag and negate any gains.


Not necessarily. Things like fans and water pumps work efficiently at a certain speed and driving them directly off the engine puts more drag than necessary on the engine.

I read an article a couple years ago about a diesel hot rod shop that built a Cummins and dropped it in a half ton standard cab 2 wd
truck and it would run in the 11s. They drove it across Georgia and averaged over 50mpg. Having driven a few Cummins trucks I have no doubt that they could get some really awesome mileage with a few tweaks and much higher gears.


Impossible to get 50 MPG in a full size truck with that engine, unless you are doing 25 MPH constant speed at 1400 RPM. Drag limits highway mileage, kinetic energy losses from braking/accelerating kill city mileage.
Link Posted: 8/22/2012 5:29:33 PM EST
Originally Posted By LIINTLICKR:
Does this animal exist?

eta: mpg


only if pulled by another vehicle.
Link Posted: 8/22/2012 5:34:17 PM EST
Originally Posted By TinLeg:
Originally Posted By SnoopisTDI:
Originally Posted By BrandonB:

Originally Posted By SouthEndXGF:
as promised earlier:

http://i856.photobucket.com/albums/ab122/southendxgf/13d03665.jpg

If you had that tuned, who did it?

My new eco supercrew 4wd is nothing close to that. Around 17.5 mixed being easy on the throttle and running 89 oct.




It's an instant number - it could have been reading 12mpg a few seconds later. I know if I'm rolling along in my VW and seeing a steady 30mpg, even the slightest incline can knock it into the teens or put it up in the 40s.

That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.


In the picture SouthEndXGF posted, it shows average MPG of 25.2. The instant is somewhere north of 30.



Those on board mileage computers are notoriously optimistic. Ill believe it if he hand calculates it.
Link Posted: 8/22/2012 5:36:44 PM EST
Originally Posted By Dagger41:
Originally Posted By Visable-assassin:
Originally Posted By SnoopisTDI:
That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.[/div]

If a vehicle does not require premium and you run premium....you really are not giving it any help....
Now if it requires premium then that is a different thing.


You are correct. So many people believe that running premium in a vehicle that does not require it gives them a performance gain. Higher octane gasoline enables the fuel to withstand higher combustion pressures before it reahes a stage of igniting before spark is added.
The fuel itself does not ad performance, it's the compression ratio of the engine that determines that.

As for the full size truck issue discussed, a 2004-2009 Duramax 2500HD can yield 30+ mpg regularly if it is kept in tune. 2010 models cannot yield the same economy due to DPF and DEF.
EPA killed the economy in the newer units with added emissions regulations.


No way in hell any dmax is getting 30mpg. Not a chance.
Link Posted: 8/22/2012 5:49:33 PM EST

Originally Posted By Dagger41:
Originally Posted By Visable-assassin:
Originally Posted By SnoopisTDI:
That said, if you ran a tank of 93 you'd probably see at least a 2mpg improvement. Might not save any money, but I'd feel better knowing my engine is running better.[/div]

If a vehicle does not require premium and you run premium....you really are not giving it any help....
Now if it requires premium then that is a different thing.


You are correct. So many people believe that running premium in a vehicle that does not require it gives them a performance gain. Higher octane gasoline enables the fuel to withstand higher combustion pressures before it reahes a stage of igniting before spark is added.
The fuel itself does not ad performance, it's the compression ratio of the engine that determines that.


Just because it doesn't require premium doesn't mean there's no benefit to it. In this case, we're talking about turbocharged, direct injected engines. It's not a riding lawn mower. ;) They will definitely take advantage of high octane gas.
Link Posted: 8/23/2012 8:09:18 AM EST
Originally Posted By SnoopisTDI:

Just because it doesn't require premium doesn't mean there's no benefit to it. In this case, we're talking about turbocharged, direct injected engines. It's not a riding lawn mower. ;) They will definitely take advantage of high octane gas.



If the motor isn't designed or tuned for premium fuel you are doing more harm than good. My truck is blown and requires premium and nothing less unless I pull the blower belt then I can run lower octane fuel, but a 8.5:1 compression motor even with cams, heads and exhaust is a dog, but unless I feel like venting my block there is no way around it. Even direct injected engine unless they are designed or tuned for the stuff its pointless.
Link Posted: 8/23/2012 8:17:16 AM EST
2013 ram 1500 will get up to 27mpg
Link Posted: 8/23/2012 8:23:51 AM EST
Originally Posted By Visable-assassin:
Originally Posted By SnoopisTDI:

Just because it doesn't require premium doesn't mean there's no benefit to it. In this case, we're talking about turbocharged, direct injected engines. It's not a riding lawn mower. ;) They will definitely take advantage of high octane gas.



If the motor isn't designed or tuned for premium fuel you are doing more harm than good. My truck is blown and requires premium and nothing less unless I pull the blower belt then I can run lower octane fuel, but a 8.5:1 compression motor even with cams, heads and exhaust is a dog, but unless I feel like venting my block there is no way around it. Even direct injected engine unless they are designed or tuned for the stuff its pointless.


The Ford owner's manual recommends Premium fuel for best performance when towing. Something like a Camry would see no benefit from higher grade fuel.

Link Posted: 8/24/2012 11:54:21 AM EST
I just saw this, it looks like the 2013 Ram with the new Pentastar V6 will be rated at 25 MPG highway. Not bad for 305 HP.

http://www.autonews.com/apps/pbcs.dll/article?AID=/20120824/OEM04/120829952/1493
Link Posted: 8/24/2012 2:47:39 PM EST

Originally Posted By mr_camera_man:
I just saw this, it looks like the 2013 Ram with the new Pentastar V6 will be rated at 25 MPG highway. Not bad for 305 HP.

http://www.autonews.com/apps/pbcs.dll/article?AID=/20120824/OEM04/120829952/1493

305 horsepower is only at wide open throttle and at a certain RPM. It does NOT generate 305 HP all the time. Likewise, fuel consumption is based on the total drag force and speed. Say it has 150 pounds force of drag at 60 MPH, that is 150 lbf X 88 ft/second. That is 13,200 lbf*ft/sec, as each HP is 550 lbf*ft/second, that is 24 HP. Most gasoline engines consume 0.45 to 0.55 pounds of fuel (mass) per horsepower-hour. So in this example, that is 10.8 pounds per hour, as each gallon weighs 6 pounds, that is 1.8 gallons per hour. Since the vehicle was covering 60 miles in that hour, that is 33.33 miles per gallon.

Diesel engines consume far less fuel per horsepower-hour, usually in the 0.36 pounds per hp-hour. This is because they have lower pumping losses, higher compression ratio (increases Carnot theoretical cycle efficiency by raising combustion temp) and diesel has slightly more energy per gallon.

Now, larger gasoline engines can be less efficient as they cruise at higher manifold vacuum which REDUCES the actual compression ratio (compress a vacuum, also why normally aspirated engines lose power at altitude). But a steep overdrive can compensate, bringing the engine into higher manifold pressure at lower RPM.


Link Posted: 8/24/2012 2:55:12 PM EST

Originally Posted By Keith_J:

Originally Posted By mr_camera_man:
I just saw this, it looks like the 2013 Ram with the new Pentastar V6 will be rated at 25 MPG highway. Not bad for 305 HP.

http://www.autonews.com/apps/pbcs.dll/article?AID=/20120824/OEM04/120829952/1493

305 horsepower is only at wide open throttle and at a certain RPM. It does NOT generate 305 HP all the time. Likewise, fuel consumption is based on the total drag force and speed. Say it has 150 pounds force of drag at 60 MPH, that is 150 lbf X 88 ft/second. That is 13,200 lbf*ft/sec, as each HP is 550 lbf*ft/second, that is 24 HP. Most gasoline engines consume 0.45 to 0.55 pounds of fuel (mass) per horsepower-hour. So in this example, that is 10.8 pounds per hour, as each gallon weighs 6 pounds, that is 1.8 gallons per hour. Since the vehicle was covering 60 miles in that hour, that is 33.33 miles per gallon.

Diesel engines consume far less fuel per horsepower-hour, usually in the 0.36 pounds per hp-hour. This is because they have lower pumping losses, higher compression ratio (increases Carnot theoretical cycle efficiency by raising combustion temp) and diesel has slightly more energy per gallon.

Now, larger gasoline engines can be less efficient as they cruise at higher manifold vacuum which REDUCES the actual compression ratio (compress a vacuum, also why normally aspirated engines lose power at altitude). But a steep overdrive can compensate, bringing the engine into higher manifold pressure at lower RPM.



I agree with everything you said... That's why I drive a diesel Passat myself. Just trying to give the guy what he asked for.
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