Why is the F-type so heavy?
#1
Why is the F-type so heavy?
Aug Road & Track has a comparo of the Porsche Boxster & Jag F-type. Curb weight for the v-6 turbo f-type is 3839 lbs. Boxster: 3155. A difference of almost 700 lbs! Thats the weight of 3 full sized adults. Both have similar dimensions. Both are 2 wheel drive 2 seaters. The Boxster is composed of a steel/aluminum chassis & body. The Jags chassis & body are all aluminum. I love the look of the f-type. But its porky at 3839 lbs. Thats only a few hundred lbs less than the current XK model.....
#2
#3
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Seems like Jaguar has suffered weight problems for a long time.
On older Jags it was fairly easy to see where the weight came from. Crawl through, around, and under the car and there was an obvious "built-like-a-tank" appearance to most everything.
Not sure why the F-Type be portly, given modern materials and engineering. Ten years ago Jaguar managed to lop several hundred pounds off the XJ8 sedan bringing it down to 3600 pounds or so, as I recall.
As always, taking it off and keeping it off are two different things
Cheers
DD
On older Jags it was fairly easy to see where the weight came from. Crawl through, around, and under the car and there was an obvious "built-like-a-tank" appearance to most everything.
Not sure why the F-Type be portly, given modern materials and engineering. Ten years ago Jaguar managed to lop several hundred pounds off the XJ8 sedan bringing it down to 3600 pounds or so, as I recall.
As always, taking it off and keeping it off are two different things
Cheers
DD
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Brutal (08-21-2014)
#5
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Apparently.
And the air is very heavy over in Old Blighty so even the tires come under scrutiny
Over the last few years I've became slightly familiar with Porsche 911s. Seems to me that the construction is "potatoe chip" ("potatoe "crisps"?) compared to Jags...even the compared to the old E-types (which probably ended up heavier than desired or intended).
That's not a criticism of old 911s, mind you. I love 'em.
Oh well. I'm talking out of my hat. I'm really not familiar with how modern Jags (or Porsches) are built.
Cheers
DD
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#9
Pobably because the Porsche makes use of a steel body. Following is my guess:
By weight most Aluminum alloys are substantially stonger than steel alloys in terms tensile strength so there is a weight advantage to using them in a structural member with a tensile load.
When you move to non-structural sheets in a street car elasticity and stiffness are more important than tensile strength and steel has an advantage there. You could use very thin aluminum in a body and come out lighter than steel but it would dent very very easily (like the aluminum bodied cars from the 60s did). Drive on the highway for 100 miles and you have a series of dents on the rockers from small stones kicked up by the front tires. Close the door a bit too hard and you have a dent. To prevent this in a mass market car you have to make the aluminum thicker and that makes it weigh more than a comparable steel sheet.
By weight most Aluminum alloys are substantially stonger than steel alloys in terms tensile strength so there is a weight advantage to using them in a structural member with a tensile load.
When you move to non-structural sheets in a street car elasticity and stiffness are more important than tensile strength and steel has an advantage there. You could use very thin aluminum in a body and come out lighter than steel but it would dent very very easily (like the aluminum bodied cars from the 60s did). Drive on the highway for 100 miles and you have a series of dents on the rockers from small stones kicked up by the front tires. Close the door a bit too hard and you have a dent. To prevent this in a mass market car you have to make the aluminum thicker and that makes it weigh more than a comparable steel sheet.
Last edited by auburn2; 04-24-2014 at 09:16 PM.
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pabanker (04-26-2014)
#10
Interesting question.
The F-Type is larger than the Boxster, so using some rough math (see image), the difference in weight is about 20% and the difference in size accounts for about half of that, or 10%.
I'd speculate a small fraction of the remainder is heavier furnishings (leather trim, etc) in the F-Type, but most of it is less efficient engineering =(
Pity, cos in addition to higher performance the 10% difference in material cost would make for some nice savings
The F-Type is larger than the Boxster, so using some rough math (see image), the difference in weight is about 20% and the difference in size accounts for about half of that, or 10%.
I'd speculate a small fraction of the remainder is heavier furnishings (leather trim, etc) in the F-Type, but most of it is less efficient engineering =(
Pity, cos in addition to higher performance the 10% difference in material cost would make for some nice savings
#11
Motorized steering wheel, motorized mirrors, motorized dash vent, motorized seats, motorized door handles, battery in trunk (more heavy copper wire), 2nd battery in trunk for ECO...
Convertibles usually weigh more than coupes due to the need for additional stiffening, and the F-type seems to be pretty stiff.
Convertibles usually weigh more than coupes due to the need for additional stiffening, and the F-type seems to be pretty stiff.
Last edited by DJS; 04-25-2014 at 08:26 AM.
#12
Aug Road & Track has a comparo of the Porsche Boxster & Jag F-type. Curb weight for the v-6 turbo f-type is 3839 lbs. Boxster: 3155. A difference of almost 700 lbs! Thats the weight of 3 full sized adults. Both have similar dimensions. Both are 2 wheel drive 2 seaters. The Boxster is composed of a steel/aluminum chassis & body. The Jags chassis & body are all aluminum. I love the look of the f-type. But its porky at 3839 lbs. Thats only a few hundred lbs less than the current XK model.....
Its a V6 Supercharged, not turbocharged
Curb weight for a V6S is 3,558 lb, not 3839. I dont know where Road and Track got that number.
The F-Type is almost 100mm longer and wider.
The F-Type isnt supposed to be a little nimble track day car.
Its a sporty muscle car. Even with the smaller engine, the Porsche is still a mid engine car. Of course it will be more responsive.
Porsche is one of the best car manufacturers in the world in the terms of technology. You cant expect a luxury car company to come out with a car and it is instantly better than the comp. It needs time. and the Boxter has had MUCH time.
Also, idk about you but i would much rather be carving some roads in an F-type than a Boxter.
I see an F type, ill turn my head. Chances are i wont even notice a Boxter in the streets.
At the end of the day it all comes down to personal preference. Each car has things it does better.
Last edited by JaguarTampa; 04-26-2014 at 11:34 AM.
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swajames (04-25-2014)
#13
Agree. Bottom line is anyone with an F Type could have bought a Boxster or Cayman. I tested the Boxster pretty extensively this time around, and I'm a prior owner of two 997s, so I know the cars and the brand well. For me, the F Type was by far the better car and that's why I bought one and didn't buy the Porsche. The Porsche is a good car, but is best described as clinical. It has little to no character and soul. The F Type has both in spades.
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#15
Aug Road & Track has a comparo of the Porsche Boxster & Jag F-type. Curb weight for the v-6 turbo f-type is 3839 lbs. Boxster: 3155. A difference of almost 700 lbs! Thats the weight of 3 full sized adults. Both have similar dimensions. Both are 2 wheel drive 2 seaters. The Boxster is composed of a steel/aluminum chassis & body. The Jags chassis & body are all aluminum. I love the look of the f-type. But its porky at 3839 lbs. Thats only a few hundred lbs less than the current XK model.....
Actually the F type is wider than the Porsche by 5 inches.
#17
Interesting question.
The F-Type is larger than the Boxster, so using some rough math (see image), the difference in weight is about 20% and the difference in size accounts for about half of that, or 10%.
I'd speculate a small fraction of the remainder is heavier furnishings (leather trim, etc) in the F-Type, but most of it is less efficient engineering =(
Pity, cos in addition to higher performance the 10% difference in material cost would make for some nice savings
The F-Type is larger than the Boxster, so using some rough math (see image), the difference in weight is about 20% and the difference in size accounts for about half of that, or 10%.
I'd speculate a small fraction of the remainder is heavier furnishings (leather trim, etc) in the F-Type, but most of it is less efficient engineering =(
Pity, cos in addition to higher performance the 10% difference in material cost would make for some nice savings
#18
1. Ian Callum wanted to retain the elongated hood for the F-type (to reflect the E-type heritage...he's on record on this point), so the car had to be a little longer stylistically. He's a big believer in proportionality so the width of the car was likely influenced by a desire to retain aspect proportionality for the length.
2. Jaguar wanted a car that could be comfortable for (increasingly wider) Western body shapes -- their traditional customer base -- so the cabin reflects that: the 5" difference in width is exactly reflected in a 5" larger cabin shoulder width for the F-Type.
#19
#20
I think:
1. Ian Callum wanted to retain the elongated hood for the F-type (to reflect the E-type heritage...he's on record on this point), so the car had to be a little longer stylistically. He's a big believer in proportionality so the width of the car was likely influenced by a desire to retain aspect proportionality for the length.
2. Jaguar wanted a car that could be comfortable for (increasingly wider) Western body shapes -- their traditional customer base -- so the cabin reflects that: the 5" difference in width is exactly reflected in a 5" larger cabin shoulder width for the F-Type.
1. Ian Callum wanted to retain the elongated hood for the F-type (to reflect the E-type heritage...he's on record on this point), so the car had to be a little longer stylistically. He's a big believer in proportionality so the width of the car was likely influenced by a desire to retain aspect proportionality for the length.
2. Jaguar wanted a car that could be comfortable for (increasingly wider) Western body shapes -- their traditional customer base -- so the cabin reflects that: the 5" difference in width is exactly reflected in a 5" larger cabin shoulder width for the F-Type.
Well said. And, I think it's also due to the fact that underneath it uses XK chassis. Which is a big car to start off with.