Cars Today Need To Go On A Diet!

[clutch-monkey]

luxury cars espeically are very heavy. why? they're supposed to be sporty. shouldn't they be light? im not talking sub 3000lbs but not close to 4000lbs.

what
no. by definition luxury cars are quieter, more comfortable, have more gismos than typical. it can be 'sporty' but in that sense it's more of a GT car...not a true performance vehicle.
it's sort of a jack of all trades deal - sure you could buy an elise and a mercedes, or you could buy one car that does both but not as well as either.
sure it's a compromise, but people are willing to live with that.
that's why cars like the M3, RS4, and even a carrera S are so popular these days; you get some performance, but you don't sacrifice so much that it's too hard to live with.

I agree. There's two big problems: one is wheels are getting bigger and heavier which adds unsprung weight and requires larger wheel wells leaving less room on the inside.

imo power is to partly to blame here as well- needs bigger brakes to stop, thus bigger wheels to fit them, and stronger components to handle the power so more bracing and reinforcing is needed, etc etc

The Insurance Institute for Highway Safety(USA) has said there is no substitute for weight.

"There are good reasons people buy mini cars. They're more affordable, and they use less gas. But the safety trade-offs are clear from our new tests,"

“All things being equal in safety, bigger and heavier is always better."

well that's just great
just don't crash...
i have a bolt in cage ready for my mini, seeing as it weighs 700kg or so.
defensive driving > safety features imo.

[Ferrer]

what
no. by definition luxury cars are quieter, more comfortable, have more gismos than typical. it can be 'sporty' but in that sense it's more of a GT car...not a true performance vehicle.
it's sort of a jack of all trades deal - sure you could buy an elise and a mercedes, or you could buy one car that does both but not as well as either.
sure it's a compromise, but people are willing to live with that.
that's why cars like the M3, RS4, and even a carrera S are so popular these days; you get some performance, but you don't sacrifice so much that it's too hard to live with.

That still doesn't quite explain why the original Golf GTI weighted 830kg and the current one 1320kg.

So if you want comfort, it has to be fat then?

[LeonOfTheDead]

That's exactly what I expected from my rethorical question.

There's no such correlation with weight and safety.

there is.

Yes there is. It's all relative to impact speed and what two masses meet...but still the heavier the vehicle the safer overall.

The Insurance Institute for Highway Safety(USA) has said there is no substitute for weight.

"There are good reasons people buy mini cars. They're more affordable, and they use less gas. But the safety trade-offs are clear from our new tests,"

“All things being equal in safety, bigger and heavier is always better."

that's incorrect.

an heavier object is carrying more energy.
considering material, design (project and form) of the structure, a smaller and lighter object could still absorb that energy in an impact.
a smaller vehicle carries less energy, therefore a properly designed heavier object isn't directly affected in an impact.
that's a general statement, as tests on the first Audi Q7s demonstrated it was less safe than a lot of other cars (being both heavier and lighter) during Euro NCAP tests, with driver reporting lesions to the feet (an issue then corrected), despite the smaller and lighter Touareg and Cayenne sisters didn't suffer the same problem.

from this restricted point of view, a tank would be the safer way to commute.

On the other hand, while an heavier vehicle decently designed could eb considered safer in an impact with a smaller and equally well designed small car than the same smaller ar itself, it could easily result way less safe in an impact against a concrete wall, for instance.
That because, considering a solid object which is much heavier and even more solid than whatever car, the car would have to absorb it's onw energy rather than discharge it on the smaller car (that's fair, isn't it?).
therefore, with equal materials, design solutions and technology, the heavier car would have to sustain much more energy in the impact, coherently with how much heavier it is than the smaller car.
It's quite obvious the two cars have similar capabilities in absorbing the nergy of an impact being designed similarly. Hence the heavier car is less safe in whichever impact not involving a smaller car.

For what regards a lack of relationship between weight and safety, here is the relationship:
a paper car is light, and completely unsafe.
a rock car is heavy, and fragile, therefore unsafe.
a steel car is somehow heavy, but safe.
an aluminum car is lighter, and safer, given the fact thicker chassis' parts are required.

so it seems there is no correlation.
BUT...Consider steel cars (the vast majority).
in the past years they were lighter than today (wondering how much of this way is chassis related), and they also were less safe. not saying adding weight is safer, but using the same material but in thicker parts IS safer, like saying you can open a sheet of paper with your fist, but try with 20 sheets.

here is the correlation, given certain parameters.
than you can use carbon fiber or other new composite materials, and have safer and lighter cars, but we both know that's not going to happen any time soon.

then you still have to face the possibility of an impact not involving another car as stated previously.

In an ideal world, we would all drive carbon fiber Elises.

[Dino Scuderia]

I say if you take the vehicles most commonly used by the masses...the heavier vehicle in collisions in that sample are the safest.

You can always find exceptions.

[clutch-monkey]

That still doesn't quite explain why the original Golf GTI weighted 830kg and the current one 1320kg.

So if you want comfort, it has to be fat then?

i guess?
i'm not talking about the same car gaining weight over the years though, more the difference between 'sporty' cars like the G35 mentioned above and actual sportscars.

as for the golf, some of it would be extra safety features yeah? imo some of it would also be the support for the extra power.

[LeonOfTheDead]

I say if you take the vehicles most commonly used by the masses...the heavier vehicle in collisions in that sample are the safest.

You can always find exceptions.

I don't take an impact against a wall as an exception.

as for the golf, some of it would be extra safety features yeah? imo some of it would also be the support for the extra power.

exactly.

[Dino Scuderia]

I don't take an impact against a wall as an exception.

That is not the common collision.

[LeonOfTheDead]

That is not the common collision.

It isn't even a rare one.
and even considering only collision with another car, by this reasoning it would only lead to heavier and heavier cars as days go by.

[NSXType-R]

The issue is, Leon, I want to agree with you but this link says otherwise.

The tests were by the IIHS, so it's not really a no name test.

Jalopnik - IIHS Small Car Test: Three Gruesome Slow-Motion Crash Videos - small car crash tests

The weird thing though, is that the info on the actual site is different...?

http://www.iihs.org/ratings/ratingsbyseries.aspx?id=593

[LeonOfTheDead]

The issue is, Leon, I want to agree with you but this link says otherwise.

The tests were by the IIHS, so it's not really a no name test.

Jalopnik - IIHS Small Car Test: Three Gruesome Slow-Motion Crash Videos - small car crash tests

The weird thing though, is that the info on the actual site is different...?

IIHS-HLDI: Honda Fit

because, as explained, the vehicle itself is safe.
in those impacts the car matched objectes with higher masses,much more solid and standing, therefore it has only to face it's own energy or that of the fake car in the side impact, and it is pretty good at it.

when facing other deformable and movable object, if they have an higher energy (more mass or either more speed, kinetic energy=mass*speed^2), the small vehicle has to face both his an the other's energies, and therefore it fails at it.
even an Hummer H2 facing an impact against a fully loaded H2 would suffer major damages.

I still stand by my arguments. in this way we would only have to buy the heaviest car every time to be safe...obviously no.
There are cars which "has" to be heavy for certain reasons like, exaggeration, a Caterpillar. But a lot of car are pointlessly heavy, and up to when these car will be running, no matter how well the smaller car is designed, it will be more vulnerable (not less safe) if lighter (by a fair margin).


Take to Fiat 500 as a reference. it's very safe, one of the best cars. Facing an impact with the Audi Q7 it suffered major damages (not that the Q7 was unharmed). but it wasn't, as stated by the ADAC, a 500's fault, but rather the own design of the Q7 not taking into count the size of smaller cars.
so the point is. up to when all cars won't be designed taking into count also other cars, there won't be any kind of really "safe" car.

[Roentgen]

Safety Regulations, new comfort features, more complicated engines.

Oh, and space to accommodate fatter people...

[Equinox]

So today I shall rant about a topic that I became aware of over the weekend. Many of you probably know this and are aware of this already but hey why not rant about it.

What would you consider light for a car these days? I'd say between 3200 and 3500lbs.

Cars are just too heavy and for what reason? with newer technologies we should be making them lighter. Lighter = better fuel economy and performance.

Why do I bring this up? I was on the highway Saturday night driving the G35 calmy. A G37S coupe turned in front of me entering the onramp of the highway so i sped up to play. It was 1:30 AM. I'm expecting the G35 to whoop my ass like no other. My car is 6 years old. I have a full tank of gas and just me, my car weighs 3300lbs give or take and puts out 260 horsepower. The G37 puts out 330 horsepower and its newer and stick. So we get on the highway, on the onramp i hear his exhuast howl, he kicks it into third. so i throw it into manual mode yank the shifter, put my car into third. then he takes off and i take off after him. pedal to the metal. he doesn't pull away much from me at all, i'm keeping up with him. So we do it again, we never managed to line up but i did try to overtake him and he didn't notice but when he did it took him a little while to pull away. i was so surprised, i was proud of my girl. we were doin 120MPH easily at some points. Now i raced an E46 M3 before, he pulled away from me like i was dust. That puts out 330 horsepower but it is a hidden powered BMW.

I got home and looked up specs. A 2009 G37S weighs 3700lbs. He may have had more then 1 person in his car. so all that extra power, goes to weight. an E46 M3 weighs 3300lbs as well, no wonder it pulled away from me like that. Imagine if i had the VQ37HR motor instead of my VQ35DE.

Does weight make that big of a difference in acceleration like that?

I looked up more cars, a new M3 weights 3700lbs too. luxury cars espeically are very heavy. why? they're supposed to be sporty. shouldn't they be light? im not talking sub 3000lbs but not close to 4000lbs.

What is becoming of the auto industry?....

Not to be nit-picky, but their are a few strange comments in the above quote.

Luxury cars are luxury cars. They have more gadgets than a jet fighter (Obviously not, but I was going for exaggeration )

Not all luxury cars are 'supposed' to be sporty. A luxury cars main objective is to be a luxury car, then performance comes second. Unless your Bentley etc. Who do both at the same time. But for them luxury is more important, so they'll be heavy in the first place with the GPS, electric seats, windows, mirrors etc. Imagine all the weight those electric motors add!!!!

Obviously weight makes a difference in acceleration. That is common sense.

Now your fuel economy for this subject doesn't make sense, since your RACING!. Obviously your not going to get good mileage when your pushing your engine to go faster than someone else who is speeding already.

Now your concerns about weight and fuel economy should be the last of your worries since your street racing on public roads. To me that is a bigger issue. (Although I could care less about people racing on streets. It's just for your comment you complain about fuel economy etc. While at the same time say you were racing on a highway going 120 MPH. Ummm... Kinda conflicts does it not!!)

Personally I am happy with the way 'most' cars are now. I really hate the new hatchback look etc. (I don't necessarily mean hatchback per say, more like the shrinking size of our cars) Like the new 370Z. Now don't get me wrong I like the car, but I like to 350Z better. I don't like the round look of some newer cars.

Now am not saying I like 'large' cars, I'm just saying I don't want all of our cars to look like Smart Cars. I mean what's the point of making a car that small? Really, what is the point? Is it not possible to make a car that is just as efficient as the Smart Car, but in a big bigger vehicle. I hate these small cars.. Personally I see no point to them other than making those that drive them look rediculous.

[digitalcraft]

Mazda RX-8 is only slightly over 3000lbs. (its also the only 4-door coupe )

Mazda3 (axela) is only slightly over 3000lbs too (or under for the MT sedan)

Compare that to say the 350Z at 3,600lb, or a mustang at 3,500lb, or even a 599GTB at 3700lbs. Its another reason I like Mazda, they make light cars. :P

The next MX-5 they're actually working to make lighter than the current one by around 10%, which would make it actually lighter than the original 1989 version. What other cars are actually lighter than the old version? It's also likely to have a diesel version.

Both the MX-5 and RX-8 are still 50/50 weight balance too.

[f6fhellcat13]

Mazda RX-8 is only slightly over 3000lbs. (its also the only 4-door coupe )

Mazda3 (axela) is only slightly over 3000lbs too (or under for the MT sedan)

Compare that to say the 350Z at 3,600lb, or a mustang at 3,500lb, or even a 599GTB at 3700lbs. Its another reason I like Mazda, they make light cars. :P

The next MX-5 they're actually working to make lighter than the current one by around 10%, which would make it actually lighter than the original 1989 version. What other cars are actually lighter than the old version? It's also likely to have a diesel version.

Both the MX-5 and RX-8 are still 50/50 weight balance too.

I think modern Corvettes are lighter than their '60s counterparts.

[Niko_Fx]

Compare that to say the 350Z at 3,600lb, or a mustang at 3,500lb.

Got the Z wrong, it's not heavier than a Mustang. The 350Z is actually at 3339lbs and a Mustang GT at 3483.

Is heavy still, I know, but 3600lbs sounds horrendous