Performance + FE suggestion for Hyundai

[DieselHybrid]

Hi,

I just made an interesting observation: The Genesis lead-acid battery in the trunk is absolutley enormous (read: heavy)!
I presume the location was chosen to aid weight distribution. Hyundai's press material proudly touts that the Genesis has a "near ideal 52/48% f/r weight distribution."

This spec must be for the V8 model- as the lighter V6 motor might be closer to the "ideal" 50/50% f/r weight distribution? Can anyone chime in on this?

Additionally, I don't believe the Genesis' over-sized battery was chosen because of vehicle electrical loads- but rather to help offset the additional weight of the Tau V8 in the nose. Again, can anyone confirm this?

Reasoning:
My wife's 8-passenger Toyota Sienna minivan with a passenger DVD entertainment system, seperate front & rear a/c units, electric sliding doors, 13 interior lights, and a JBL 12-speaker system with subwoofer utilizes a much smaller, lighter battery than the Genesis- yet the Sienna clearly has greater electrical demands.

Which brings me to the following conclusion: a lighter dry cell battery can be used to replace the massive OEM battery in the V6 Genesis trunk (not the V8- as it would further disturb the vehicle's weight distribution).

Additionally, removing the large spare tire and replacing it with tire sealant aerosol + repair kit (as BMW has done on select 2008+ model year vehicles) would further reduce unnecessary vehicle mass..

Combined, these two weight saving measures could potentially reduce the vehicle weight by +70lbs and bring the weight distribution closer to the ideal 50/50% in the V6 model Genesis.

Why bother?
Reduced vehicle mass would positively contribute to improved acceleration/deceleration and fuel economy. Hyundai's engineers are well aware of this as demonstrated in their choice of rather expensive aluminum for the hood and various suspension components. The over-sized battery and spare tire seem like low-hanging fruit in comparison.

Hyundai may wish to consider these measures to meet upcoming CAFE requirements.

Meanwhile, present Genesis V6 owners interested in boosting their vehicle's performance and economy may wish to further investigate this.

Peace.

 

[JOwest]

The V6 has the weight ratio of 52/48 f/r. The V8 is 54/46 f/r. Use a smaller battery and remove the spare will tire make the weight distribution even worse! Because the rear will be much lighter than the front. Not good!

 

[DieselHybrid]

@JOwest-

52/48% for the V6 and 54/46% for the V8- thanks! This should help explain the automotive press' preference of the V6's handling over the V8's.

One would think Hyundai engineers could think of a more elegant solution to an ideal weight distribution than stuffing an oversized battery in the trunk. Examples: use a dry sump lubrication system to lower and shift the motor's CG aft. This would lower the CG and also reduce the vehicle's polar moment of inertia.

At +3,748 lbs for the V6 sedan (and over 4,000 lbs for the V8 sedan), there appears to be plenty of room to improve!
To paraphrase Colin Chapman: "For better performance, add lightness!"

It is not my intention to play armchair quarterback to the really commendable work Hyundai has accomplished with the Genesis.
I was merely noting that there is a rather oversized battery in the trunk- when it appears a smaller one would do.

My suggestion could still be beneficial if a similar amount of weight could be removed forward of the vehicle's CG. Anyway, I offer something that current V6 owners may further investigate.

Peace.

 

[Gimli]

I was merely noting that there is a rather oversized battery in the trunk- when it appears a smaller one would do.

I'd much rather have a battery that weighs a bit more than not be sure whether the car will start or not when the temps drop below -20*, which isn't unusual around here.

Japanese cars are known around here for having grossly under-spec'ed batteries which do not support the extreme conditions we drive and live in.

If you're looking for weight savings over functionality you're looking in the wrong category of cars.

 

[DieselHybrid]

@Gimli

Functionality requires having overweight vehicles? Why? Since when have weight savings and functionality been mutually exclusive?

I was merely noting that the Genesis (and most every other vehicle on the road today) could be engineered to be lighter. Why must a "sports sedan" like the Genesis weigh as much as my wife's 8-passenger Toyota Sienna minivan? (Now that's a vehicle that oozes "functionality!")

With more stringent CAFE requirements just around the corner- automakers will have no choice but to further exploit weight savings in their vehicle line-ups.

Peace.

 

[Gimli]

Functionality requires having overweight vehicles? Why? Since when have weight savings and functionality been mutually exclusive?

I never said they were.

I was merely noting that the Genesis (and most every other vehicle on the road today) could be engineered to be lighter.

They could also be engineered to be faster. Or heavier. Or less flexible. Or more expensive. Or any other way the manufacturer figures will sell more. Make no mistake: selling more units is what all manufacturers should be after, not some ideals some people pull out of thin air. Maybe the American manufacturers wouldn't be in so much trouble if they'd just remembered to make cars people wanted to buy at the prices people were willing to pay for.

Why must a "sports sedan" like the Genesis weigh as much as my wife's 8-passenger Toyota Sienna minivan? (Now that's a vehicle that oozes "functionality!")

Why must you compare apples to oranges?

With more stringent CAFE requirements just around the corner- automakers will have no choice but to further exploit weight savings in their vehicle line-ups.

Weight reduction is only one of countless factors that affect fuel mileage. Only looking at one aspect, to the detriment of others, is counter-productive.

 

[DieselHybrid]

@ Gimli

"If you're looking for weight savings over functionality you're looking in the wrong category of cars."
Not sure what you attempted to communicate- but you appear to imply that functionality requires additional weight.

I compare an 8-passenger minivan to the Genesis "sports sedan" because, sadly, they weigh about the same.

Finally, there really isn't a "countless" number of factors that affect fuel efficiency. Probably the biggest modifaction one can do to improve efficiency is to adjust the nut that connects the driver's seat to the steering wheel.

Anyway, here's a short list of controllable design factors that have a direct effect on vehicular fuel economy:

Engine losses (heat loss, internal friction: cylinder, valvetrain, bearings)
Aerodynamic Drag
Tire Rolling Resistance
Drivetrain losses (hydraulic losses, internal friction)
Vehicular peripheral losses (electrical, hydraulic, pwr systems)

Please explain how reducing vehicle weight would be detrimental to any one of them.
Thanks!

Peace.

 

[Gimli]

"If you're looking for weight savings over functionality you're looking in the wrong category of cars."
Not sure what you attempted to communicate- but you appear to imply that functionality requires additional weight.

Read the rest of my post, that may help you understand.

I compare an 8-passenger minivan to the Genesis "sports sedan" because, sadly, they weigh about the same.

...so I guess I should compare my Genesis to my brother's Corvette because they're both black.

Finally, there really isn't a "countless" number of factors that affect fuel efficiency. Probably the biggest modifaction one can do to improve efficiency is to adjust the nut that connects the driver's seat to the steering wheel.

Anyway, here's a short list of controllable design factors that have a direct effect on vehicular fuel economy:

Engine losses (heat loss, internal friction: cylinder, valvetrain, bearings)
Aerodynamic Drag
Tire Rolling Resistance
Drivetrain losses (hydraulic losses, internal friction)
Vehicular peripheral losses (electrical, hydraulic, pwr systems)

Please explain how reducing vehicle weight would be detrimental to any one of them.

*sigh*
Again, apples to oranges. Please note that weight is not on that list. Since there are countless factors that can affect your "short list", including weight, my previous statement stands.

 

[DieselHybrid]

I wrongly assumed you might have a rudimentary understanding of basic Physics.

I mentioned the rather unfortunate similarity between an 8-passenger minivan and the Genesis sedan is that they both happen to weigh a rather portly ~4,000lbs. This is a simple statement of fact in a discussion centering around vehicular weight.

Physics:
With the exception of aerodynamic drag, reducing vehicular weight would directly and indirectly benefit every one of the factors that affect fuel economy.

Engine losses- reduced as the engine does not need to work as hard to overcome vehicular inertia. Frictional losses are smaller and less fuel is burned- which also lowers heat loss.

Drivetrain losses- reduced as the transmission frictional forces decrease with reduced load.

Peripheral losses- reduced in the case of reduced power steering requirements, and lower engine cooling losses

But possibly the biggest benefactor of reduced vehicular weight is Rolling Resistance (RR)
Rolling resistance is directly proportional to vehicular weight:
RR= Crr*tire contact area*weight

As a vehicle travels on a road surface, the tires themselves elastically deform and release energy in the form of both sound and heat- with every revolution. Additionally, on the molecular level, the tire both adheres and forcibly separates to/from the road surface- again with every revolution. Combined these phenomena are said to create a rolling resistance (RR) which is always present and offers a constant resistance to rotation that the vehicle's powerplant must overcome. Up to about 35mph, rolling resistance is greater than aerodynamic drag. Beyond 40mph, aerodynamic drag is greater and increases as the square of velocity. (Power to overcome aero drag varies as the cube of velocity.) But, as I mentioned, RR is always present & constant regardless of vehicle speed.

Therefore we can see why reducing vehicular weight is both beneficial and desirable in our quest to improve efficiency.

Peace.

 

[Gold Z]

Diesel is correct. However, to reduce weight from the rear of the car might improve efficiency but it is counter productive it it shifts weight forward on an already nose heavy vehicle thus negatively effecting handling and braking.

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[Gimli]

I wrongly assumed you might have a rudimentary understanding of basic Physics.

Whatever. I thought you had a rudimentary understanding of the English language but you seem determined to argue points I don't make and ignore the points I do make.

Have fun in your dream world where you can't be wrong.

 

[DieselHybrid]

Diesel is correct. However, to reduce weight from the rear of the car might improve efficiency but it is counter productive it it shifts weight forward on an already nose heavy vehicle thus negatively effecting handling and braking.

Agreed! The over-sized battery appears to serve a secondary purpose as ballast. If this excess weight is removed from the rear- weight must also be removed forward of the CG to preserve balance- which appears to be best left to Hyundai's engineers. Don't try this at home, unless you have accurate wheel scales and you think you know what you're doing.

@Gimli-
Sorry to hear you feel that way. Really. In retrospect, I should have worded my quote above differently. Sorry! I tried to address every point of your responses patiently and as best I could. Please don't go away mad.

Peace.

 

[Tufast]

Although, I did find the above conversation interesting, I don't believe that the huge battery in the Genesis' trunk was designed to be large & heavy just to address the desire for near perfect weight balance geometry by positioning it in the rear of the vehicle. Instead, that large heavy battery is being used to operate all the numerous electrical systems & cool amenities that this vehicle comes packed with, then still have the capacity to start the thing in extreme hot or cold temperatures.

After Hyundai seen that they were going to have to use such an enormous battery to supply the juice to keep this mobile land yacht functioning, did they decide "hey lets put in the rear to help balance out some of this weight bias". I don't blame them because my 4,050 lb BMW 540i has a huge frickin battery as well & guess where, yep, in the trunk.

If you take the time to look under the hood of Hyundai's upper end vehicles: Azera, Veracruz, Entourage, SantaFe, etc, they all have large 700cca batteries as well. Hell, there's even a TSB out from Hyundai to their svc/sales depts to remove the IAD fuse from the Veracruz until the vehicle is going to be looked at by a customer to be sold in order to reduce battery drain from all the operating systems still running on the vehicle even though it is parked & off. After a couple of weeks of sitting if it is not cranked, the battery will be dead & have to be charged.

DieseHybrid, I guess Toyota has just got it together with regards to the draw their electronics has on their batteries since your Sienna uses such a small battery & the Hyundai Entourage uses a fairly large battery. Not to mention the enormous battery that the Genesis sedan uses. Although. it does not take that much juice to run most systems, yet it does take alot of cold cranking amps to start a vehicle. But, if your trying to save weight, which I know a little about, just switch over to an Odyssey dry cell or something of the like. But, I agree that a sedan is not a car that most people buy with the intention of lightening up.

 

[Mark_888]

I compare an 8-passenger minivan to the Genesis "sports sedan" because, sadly, they weigh about the same.

The Genesis will hold 8 people so long as 3 of them are dead. It really makes no sense to compare a sedan with a mini-van having a squared off back-end. If all 8 people had to be alive, I would put 5 in the Genesis and make the other 3 walk or ride a bike to save energy.

Also, the Toyota Sienna minivan (2009) has a 6 cylinder engine and weighs 4,310 lbs, and the Genesis V6 is 3,748 lbs, and the V8 is 4,012 lbs. So your numbers are a bit off. Hyundai actually did a number of things to reduce the weight, such as using aluminum for the hood instead of steel.

It seems doubtful to me that they would “oversize” the battery to any significant degree, but more info is needed on that. Of greater concern is where can one find a replacement (it doesn't appear to be a standard size—but I don’t know that for sure), and how much will it cost if I have to buy one at a dealer?

 

[DieselHybrid]

The Genesis will hold 8 people so long as 3 of them are dead. It really makes no sense to compare a sedan with a mini-van having a squared off back-end. If all 8 people had to be alive, I would put 5 in the Genesis and make the other 3 walk or ride a bike to save energy.

Also, the Toyota Sienna minivan (2009) has a 6 cylinder engine and weighs 4,310 lbs, and the Genesis V6 is 3,748 lbs, and the V8 is 4,012 lbs. So your numbers are a bit off. Hyundai actually did a number of things to reduce the weight, such as using aluminum for the hood instead of steel.

It seems doubtful to me that they would “oversize” the battery to any significant degree, but more info is needed on that. Of greater concern is where can one find a replacement (it doesn't appear to be a standard size—but I don’t know that for sure), and how much will it cost if I have to buy one at a dealer?

Yet again, the ONLY reason why I even mentioned the Genesis and the Sienna minivan in the same breath was due to their similar weights- not passenger capacity (whether alive or dead).

Our 2005 8-passenger Sienna weighs 4170lbs with the 8th seat installed, 4080lbs without. Sorry to hear that the newer Sienna's are also following the same weight gain trajectory as the rest of the car market. (it wasn't all that long ago when the average vehicle weighed a whopping ~2,800 lbs). Yes, yes, we've come a long way in the name of safety.

The fact is you CAN make cars both "safer" AND lighter- you just need to be smart about it.

While the Genesis' (V6 at 3748lbs, and V8 at 4012lbs) listed weights may seem "acceptable" for a "sports sedan" in today's market. It appears to me that all new cars and trucks need to go on a strict diet!

I applaud the use of aluminum and forged components in the Genesis. (I'd hate to think how much more it would have weighed had Hyundai "cheapened" the Genesis with conventional steel components for US consumption.) I look forward to the day when aluminum, carbon composites, polymers, and titanium components will become commonplace on vehicles.

LED headlights and lighting systems would help reduce vehicular electrical loads- and perhaps reduce the need for a large lead-acid battery in the trunk.

Combined, these weight saving features would enable the use of smaller- turbocharged direct injection engines with similar if not better overall performance- further reducing vehicular weight and decreasing our consumption of foreign oil.

Suggestion for Hyundai:
Consider a Genesis sedan powered with the upcoming coupe's 2-liter turbo 4 cyl. Add direct injection for +260hp & 260ft-lbs torque, making it ~200lbs lighter than the V6 Genesis sedan (~<3500lbs), and a 50/50 weight distribution, allowing +26/32mpg cty/hwy, all with a -$2000 lower pricepoint. Just a thought to consider when CAFE limits are increased. Oh, and it's coming!

Improved safety and performance, with better fuel economy...? It's a welcomed trend!

Peace.

 

[ConceptVBS]

Genesis Coupe curb weights:

CURB WEIGHT

V6 manual / automatic


3,389 / 3,397 lbs.

2.0-liter manual / automatic


3,294 / 3,362 lbs.


The weight distribution is around 54/46. Yeah, slight understeer.

 

[scottdk]

In reference to the battery being so large, the dealership explained the size was do to all the electronic load with the Tech package.

The 5 extra lbs. it weighs is changes nothing.

 

[SCVDon]

Don't want to add any flaming material, but I just hope the battery used in our Genesis lasts longer than the OEM batteries in our previous Hyundai cars. Both our formerly owned XG350 and our still owned Sonata had batteries that lasted about 2-1/2 years after purchase. Both were pro-rated since warranty doesn't fully cover cost to replace them after 2 years. Don't know if S. Calif. heat killed them or just normal expected lifetime. Our always in the shop Lincoln had a battery that went 9 years before needing replacement. About the only good thing regarding the LS that I could brag about.

 

[Mark_888]

Hyundai will be introducing direct injection technology, probably in the upcoming Sonata makeover expected in early 2010. I doubt there are any plans for a 2.0 Turbo on the Genesis Sedan, but maybe a slightly larger turbo could be offered.

The volume of Genesis sedans right now is not enough for Hyundai to worry about how it affects CAFE, but it were an issue, why would they offer the V8?.

 

[Tufast]

Don't want to add any flaming material, but I just hope the battery used in our Genesis lasts longer than the OEM batteries in our previous Hyundai cars. Both our formerly owned XG350 and our still owned Sonata had batteries that lasted about 2-1/2 years after purchase. Both were pro-rated since warranty doesn't fully cover cost to replace them after 2 years. Don't know if S. Calif. heat killed them or just normal expected lifetime. Our always in the shop Lincoln had a battery that went 9 years before needing replacement. About the only good thing regarding the LS that I could brag about.

Don, I know exactly what you're talking about regarding Hyundai "factory" batteries. The batteries that actually come in all Hyundais, except the Genesis, are by a company named Solite & are a POS. The replacement batteries that go in when you have them replaced (under warranty or not) at the dealer are manufactured by Interstate Battery Corp & are very good quality batteries. I would rank them above DieHard & they retail in the Hyundai parts computer for $165.00 for the 700cca for the 6cyls.

I wish Hyundai would just put the expensive batteries in the car in the 1st place. But, if they are coing to cut corners, I'd rather it be a cheap easy fix like a battery, rather than a more expensive, hard to get to part...LoL

Since I work for a Hyundai dealership, I get some insight that others may not have. My personal guess to the reason Hyundai uses these "cheap" batteries to start with is that these cars do a lot of sitting at docks, holding lots, on trucks, & on dealers lots, giving ample time for the battery to get drained & go dead. We replace a lot of batteries on the lot at the dealership I work at. At $140.00 (4cyl), $155.00 (6cyl), & Genesis even more^^^, I don't think Hyundai wanted to drop the expensive batteries in there from the get go.