RE: Light cars are not the answer: Tell Me I'm Wrong
Discussion
Definitely one to argue about over and over.
I got my car due to it being a lightweight special with only two seats.
However, we have a RR Wraith that weighs going on 3000 tonnes, and if it didn't weigh that much wouldn't feel anything like it feels to drive as it is.
Mimicking others, but its horses for courses for sure.
And obviously different cars suit different weights. My Stradale at ~1300kg would be amazing. A Vauxhall Astra at ~1650kg is not a good idea...
I got my car due to it being a lightweight special with only two seats.
However, we have a RR Wraith that weighs going on 3000 tonnes, and if it didn't weigh that much wouldn't feel anything like it feels to drive as it is.
Mimicking others, but its horses for courses for sure.
And obviously different cars suit different weights. My Stradale at ~1300kg would be amazing. A Vauxhall Astra at ~1650kg is not a good idea...
Vetteran said:
I remember years ago I purchased a Porsche 2.7 RS and drove it through France on the Autoroute. I was doing about a hundred when the car seemed to jump slightly.Later when I spoke to Autofarm about this they said "don't worry they all do that". Another time again on the Autoroute there was a huge downpour I slowed to about forty and turned the steering to change lanes nothing happened I just kept travelling in a straight line. I slowed further and eventually pulled onto the hard shoulder and waited for the rain to stop. In my current car Mercedes SL it is completely stable at speed on a motorway and to date no hairy moments in the rain.Apart from the obvious huge differences between the two cars large weight difference
:cough:Tyre technology
Suspension geometry
Weight distribution
Aerodynamics
Driving style
Weight has very little to do with it - your comment is largely specious reasoning / wishful thinking.
The biggest decider on a how "sporting" a car feels to the driver and occupants is the "tuning" and calibration of that car, rather than the basic components. This is because all basic subsystems are engineered to a good enough level, that changes in architecture are only bringing minor improvements.
For example, this is the front suspension of the new XE, which the article hopes will steer "nicely" because it is double wishbone:
And here is another car's front suspension:
So, by relation, that second car must handle and steer really well. However, that second set of independent dual wishbone, all alluminium front suspension is from, yup, an Audi A4.......
It's all about the target audience and the tuning!
For example, this is the front suspension of the new XE, which the article hopes will steer "nicely" because it is double wishbone:
And here is another car's front suspension:
So, by relation, that second car must handle and steer really well. However, that second set of independent dual wishbone, all alluminium front suspension is from, yup, an Audi A4.......
It's all about the target audience and the tuning!
jamieduff1981 said:
For something like a Jag XE, which is first and foremost a passenger car - can you explain how you correctly valve the dampers so that the car offers a good ride quality when empty bar the driver and a few litres of fuel as well as still driving properly when at maximum gross weight?
Clearly, mass damping is a function of the mass to be damped. Cars are indeed a compromise but it's less of a compromise if the sprung mass doesn't really change - e.g. a single seater racing car. The driver remains constant and the fuel load varies - that's it. A 5 seat passenger car with a large boot and a 60 litre fuel tank can probably vary in mass by half a tonne from empty to fully laden. You can't "just get correctly valved dampers" for something which weighs 1500kg one day and 2000kg the next.
In that respect, something like a 2.7 tonne Discovery varying its payload by half a tonne has much less effect on the damping that it has on an 1100kg Sierra varying its payload by half a tonne.
Yes it's possible to change the viscosity of the fluid used with additives in the damper fluid this can be done while the car is moving and has been around for years in various forms. There are also a few people working on adjustable valve dampers. Again this is all down to the fact that there is very little R&D going into lightweight road cars. Engineers find solutions to problems this is a very simple problem to solve.Clearly, mass damping is a function of the mass to be damped. Cars are indeed a compromise but it's less of a compromise if the sprung mass doesn't really change - e.g. a single seater racing car. The driver remains constant and the fuel load varies - that's it. A 5 seat passenger car with a large boot and a 60 litre fuel tank can probably vary in mass by half a tonne from empty to fully laden. You can't "just get correctly valved dampers" for something which weighs 1500kg one day and 2000kg the next.
In that respect, something like a 2.7 tonne Discovery varying its payload by half a tonne has much less effect on the damping that it has on an 1100kg Sierra varying its payload by half a tonne.
Edited by bnracing on Thursday 8th January 13:35
the whole Nissan weight vs aero vs grip vs general understanding has been done a few times over the years... here is the original article where the infamous quote came from and then the comments where it was discussed and then when Nissan said they were going to shave 8sec off their ring time:
http://www.pistonheads.com/gassing/topic.asp?t=760...
and here
http://www.pistonheads.com/gassing/topic.asp?t=106...
http://www.pistonheads.com/gassing/topic.asp?t=760...
and here
http://www.pistonheads.com/gassing/topic.asp?t=106...
I know an Elise can Eat a Mustang round a track etc etc. Well yes it can in the same way a fly can out manouvere a Turkey.
I think the answer is somewhere in the middle.. There are some good examples of cars that have a fine balance between weight and power. Overall you cannot beat outright power for mid range and top end but there are some heavy cars that handle amazingly well. Most of the time it is down to the driver and I have seen more people run out of talent in an Elise than an M5! But In general I do think that mid size family cars like Golfs etc are far too heavy and laden with crap.. But a big barge is meant to be a sturdy, stout thing and that does not mean it has to be very thirsty or wallowy. Look at something Like a BMW 530D... Cant argue with the overall package of performance, handling and economy.
In sporty cars I prefer something around 1500kg... and at least 300 HP... makes sense to me
I think the answer is somewhere in the middle.. There are some good examples of cars that have a fine balance between weight and power. Overall you cannot beat outright power for mid range and top end but there are some heavy cars that handle amazingly well. Most of the time it is down to the driver and I have seen more people run out of talent in an Elise than an M5! But In general I do think that mid size family cars like Golfs etc are far too heavy and laden with crap.. But a big barge is meant to be a sturdy, stout thing and that does not mean it has to be very thirsty or wallowy. Look at something Like a BMW 530D... Cant argue with the overall package of performance, handling and economy.
In sporty cars I prefer something around 1500kg... and at least 300 HP... makes sense to me
otolith said:
The comment about weight providing more grip seems to be contrary to both basic physics and real world lateral g figures.
I believe Mizuno mis-interpreted the question as 'what benefits does a higher weight bring?'.He seemed to say that the contact patch of the tyre is more consistent, with more weight pressing down on it. Perhaps he confused aero weight with body weight?
I thought that body weight made no difference to the consistency of the contact patch, as the car body is sprung?
I think that most of the difference that people feel between heavy and light cars, is due to the difference in length/wheelbase relative to width/track. Also you need exponentially larger brakes and tyres, to get the same performance from a heavier car. With rear wheel steering, adaptive damping and bigger brakes/tyres, the disadvantage of a heavier weight must be smaller.
You tend to get better value for money with smaller and lighter cars. Buying and running costs tend to be cheaper for the same performance. However there's usually slightly more noise, a slightly worse quality interior, and a slightly less stable ride. It's a trade off,
I know Harris likes small, light French hot hatches, probably because they feel faster at lower speeds. Plus light and short FWD cars, are more likely to have lift off oversteer. Harris loves oversteer.
To me lighter means like for like cheaper to buy, cheaper to run, and a faster response to driver inputs. Heavier means the opposite.
J4CKO said:
I don't buy it that the electronics are responsible for the biggest part of the lap times, it has to be basically right to do it in the first place, the GTR's pace is down to 550 bhp, massive grip, good aerodynamics (for a road car), four wheel drive traction and some very talented engineers.
The electronics work to improve things but switch it all off its still massively fast, in the hands of a pro driver I suspect it wont make much difference to lap its times, it isn't like a Eurofighter, i.e. cant be flown without the computers keeping it all together.
Pull the ecu out of one, and see how far you get... The electronics work to improve things but switch it all off its still massively fast, in the hands of a pro driver I suspect it wont make much difference to lap its times, it isn't like a Eurofighter, i.e. cant be flown without the computers keeping it all together.
They have electronic rear wheel steering, diff/transfer box and highly complicated electronic transmission control.
Thank god I'm only 74, & not as old as this bloke. I wonder how old I'll have to be before I want to drive a truck.
The best handling car I ever drove was my 1962 F2 Brabham. It sat on the grid at 1056 Lbs., & had all the grip you could ask for.
A simple streamlined car, no wings or any other synthetic garbage required. It easily out cornered heavier, be-winged, 5 years younger F1s, & even at Bathurst could out lap most of them in the wet. Yes I did lap quicker in the F1 Brabham Repco, but those 2 long straights had a bit to do with that.
For a long drive, I'll take the TR8 every time. At 1085 Kg it is the best long distance car I've ever driven. Hell I can even walk at the end of 1100 kilometres in it, & I've yet to find anything else I can say that about, except the TR7 of course.
The best handling car I ever drove was my 1962 F2 Brabham. It sat on the grid at 1056 Lbs., & had all the grip you could ask for.
A simple streamlined car, no wings or any other synthetic garbage required. It easily out cornered heavier, be-winged, 5 years younger F1s, & even at Bathurst could out lap most of them in the wet. Yes I did lap quicker in the F1 Brabham Repco, but those 2 long straights had a bit to do with that.
For a long drive, I'll take the TR8 every time. At 1085 Kg it is the best long distance car I've ever driven. Hell I can even walk at the end of 1100 kilometres in it, & I've yet to find anything else I can say that about, except the TR7 of course.
bnracing said:
Ride comfort has nothing to do with weight. If you have correctly valved dampers and correctly setup suspension with low unsprung weight you will have a fantastically comfortable and rewarding car to drive.
I am a massive Alfa fan but they have never been known for building cars with correctly setup dampers for English roads. Also another down fall of the 4c is its massive heavy wheels and low profile tyres neither of which suit a lightweight car.
Who, out of todays manufacturers would you consider to have correctly set up suspension for British roads? Ford and Jaguar?I am a massive Alfa fan but they have never been known for building cars with correctly setup dampers for English roads. Also another down fall of the 4c is its massive heavy wheels and low profile tyres neither of which suit a lightweight car.
Edited by bnracing on Thursday 8th January 12:40
I thought that the Peugeot 306 was a good compromise of ride and handling at the time but maybe I'm looking through rose tinted glasses.
bnracing said:
For me as a Automotive and motorsport designer lightweight is the only way.
There are no advantages to heavy cars other than the added comforts inside for a world of lazy drivers. To think that once we had to manually wind down a window seems a very distance memory. Most of us would rather carry around all the extra weight or motors and electrics because it's too much effort to move our arms a little.
Ride comfort has nothing to do with weight. If you have correctly valved dampers and correctly setup suspension with low unsprung weight you will have a fantastically comfortable and rewarding car to drive. Oh and wheels and tyres that are suitable for a light weight car does not mean 19inch wheels with low profile tyres. The lighter the car the smaller the wheel diameter and the bigger the tyre profile required.
It's also down to development, you need to look at how many good 1500kg+ cars are designed and built each year, thousands of them. Compared to the number of mass produced good quality low weight cars under 900kg designed each year which you could count on one hand if any at all.
There has been very little development into lightweight cars and suspension, damping and steering for light weight road cars.
I have seen a post about heavier cars having better steering feel. This is crazy and completely wrong. Weight has nothing to do with this. A lightweight car will always be more responsive and with a good steering systems give far better feedback due to very little if any assistance needed.
I am a massive Alfa fan but they have never been known for building cars with correctly setup dampers for English roads. Also another down fall of the 4c is its massive heavy wheels and low profile tyres neither of which suit a lightweight car.
Agree 100 %
Have had quite a few different cars ...ones that stand out for me were
Peugeot 205 gti
Lotus Elise series 1
Porsche 914-6
All light ...and so much fun ..lots of feel and soul .
Another good one is my mgf vvc ....a very underrated car , around 1100 in weight ? 140 ish hp ...
The hydrates suspension .. Very very comfy on bumps but also a fun blast on twisty bits ...mgf vvc engine I believe only weighs 100 kg ...car goes to 60 in 7 sec
Where our audi tt has 225 hp ? Weighs over 1400 kgs ...only half a second faster to 60 ...and is dead drive ...solid but dead
Weight loss for the car and owner ... All feels better
Eating pies might give you more grip on your plates of meat but your love handles get all wobbly in the corners
January 12:40[/footnote]
There are no advantages to heavy cars other than the added comforts inside for a world of lazy drivers. To think that once we had to manually wind down a window seems a very distance memory. Most of us would rather carry around all the extra weight or motors and electrics because it's too much effort to move our arms a little.
Ride comfort has nothing to do with weight. If you have correctly valved dampers and correctly setup suspension with low unsprung weight you will have a fantastically comfortable and rewarding car to drive. Oh and wheels and tyres that are suitable for a light weight car does not mean 19inch wheels with low profile tyres. The lighter the car the smaller the wheel diameter and the bigger the tyre profile required.
It's also down to development, you need to look at how many good 1500kg+ cars are designed and built each year, thousands of them. Compared to the number of mass produced good quality low weight cars under 900kg designed each year which you could count on one hand if any at all.
There has been very little development into lightweight cars and suspension, damping and steering for light weight road cars.
I have seen a post about heavier cars having better steering feel. This is crazy and completely wrong. Weight has nothing to do with this. A lightweight car will always be more responsive and with a good steering systems give far better feedback due to very little if any assistance needed.
I am a massive Alfa fan but they have never been known for building cars with correctly setup dampers for English roads. Also another down fall of the 4c is its massive heavy wheels and low profile tyres neither of which suit a lightweight car.
Agree 100 %
Have had quite a few different cars ...ones that stand out for me were
Peugeot 205 gti
Lotus Elise series 1
Porsche 914-6
All light ...and so much fun ..lots of feel and soul .
Another good one is my mgf vvc ....a very underrated car , around 1100 in weight ? 140 ish hp ...
The hydrates suspension .. Very very comfy on bumps but also a fun blast on twisty bits ...mgf vvc engine I believe only weighs 100 kg ...car goes to 60 in 7 sec
Where our audi tt has 225 hp ? Weighs over 1400 kgs ...only half a second faster to 60 ...and is dead drive ...solid but dead
Weight loss for the car and owner ... All feels better
Eating pies might give you more grip on your plates of meat but your love handles get all wobbly in the corners
January 12:40[/footnote]
As I said in the GT-R article, weight is good for grip only if the car is moving in a straight line. When you turn into a corner that weight is fighting AGAINST the grip as it wants to go straight on. The comparison to an F1 car's downforce is complete b
ks. The F1 car is still lightweight, so doesn't have the 1000kg downforce as 1000kg of inertia to turn into a corner.
ks. The F1 car is still lightweight, so doesn't have the 1000kg downforce as 1000kg of inertia to turn into a corner.otolith said:
The comment about weight providing more grip seems to be contrary to both basic physics and real world lateral g figures.
Quite. Weight is the downward force caused by gravity acting on a cars's mass (F=mg), this can be augmented by aerodynamics so that the car's weight is effectively increased. However, the mass is unchanged (Relativistic effects notwithstanding), and its this that will figure in the (fictitious) centrifugal force the car experiences when cornering. Using increased Edited by SteveO... on Thursday 8th January 14:46
BritishRacinGrin said:
Having said that, Lotus suspension is fantastically compliant considering how well they handle, this is a trick many manufacturers can't pull off.
Indeed on UK roads Evora actually rides slightly better than my Audi A6 did. It has the same size and profile tyres on the rear as the Audi had all round and it is considerably lighter"One company I like very much is Jaguar Land Rover. Oh it plays the lightness publicity game for all it's worth, for example bellowing about the weight saving achieved by the new aluminum body on the forthcoming Jaguar XE. But when the kg figure was finally revealed at 1,470kg for the lightest petrol-engined version, there was disappointment in these parts."
Noticed that too when it came out...
So the "leightweight" (and not so big) Jaguar Xe is quite a bit heavier than the Alfa Romeo 159, which was decleared as being too heavy by half the European car press.....
We live in a strange world.
Noticed that too when it came out...
So the "leightweight" (and not so big) Jaguar Xe is quite a bit heavier than the Alfa Romeo 159, which was decleared as being too heavy by half the European car press.....
We live in a strange world.
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