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Why is the Z4 Coupe 10kgs heavier than the convertible?

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Old 09-15-2007, 07:21 PM
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Why is the Z4 Coupe 10kgs heavier than the convertible?

I've asked this on another forum w/o success. Very strange why the coupe is heavier. Any enlightened answer? Thanks.
 
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Old 09-16-2007, 12:01 AM
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The roof extends all the way to the end/back of the car and thats a whole lotta roof to be covering up
 
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Old 09-16-2007, 12:15 AM
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Metal is heavier than canvas.
 
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Old 09-16-2007, 02:46 AM
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^ But traditionally convertibles are heavier because even though they lack a solid roof, they require steel supports inside the frame and chassis and body to make up for lost rigidity. Compare 997 variants or E46 M3s...
 
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Old 09-16-2007, 03:29 AM
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why? because the Z4 was originally designed as an open top sports car. so it was always designed to have a rigid frame to make up for the lack of roof.

so as others have said, metal weighs more than fabric, and the metal roof reaches alot further aft than the canvas roof has to.
 
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Old 09-16-2007, 03:29 AM
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Originally Posted by vtgts300kw
why? because the Z4 was originally designed as an open top sports car. so it was always designed to have a rigid frame to make up for the lack of roof.

so as others have said, metal weighs more than fabric, and the metal roof reaches alot further aft than the canvas roof has to.
Precisely, its almost always the other way around but not with the Z.
 
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Old 09-16-2007, 03:41 AM
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Originally Posted by vtgts300kw
why? because the Z4 was originally designed as an open top sports car. so it was always designed to have a rigid frame to make up for the lack of roof.

so as others have said, metal weighs more than fabric, and the metal roof reaches alot further aft than the canvas roof has to.
That makes sense, but I dunno why they didn't remove some of the rigidity now that it has a proper roof, thereby lowering the weight.
 
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Old 09-16-2007, 03:48 AM
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^^^^^

I made sense, you however do not.

They would have to re-engineer the whole car to do that. Waste of $$

I prefer the roadster. The Coupe looks awkward. And i actually prefer driving the roadster to for some reason.

And where have you been Felix? You must have some new pics for us.
 

Last edited by vtgts300kw; 09-16-2007 at 03:50 AM.
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Old 09-16-2007, 05:29 AM
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Originally Posted by vtgts300kw
^^^^^

I made sense, you however do not.

They would have to re-engineer the whole car to do that. Waste of $$

I prefer the roadster. The Coupe looks awkward. And i actually prefer driving the roadster to for some reason.

And where have you been Felix? You must have some new pics for us.
Ok, so it's not as simple as just removing the extra weight then (or else they would've done so, I suppose). I see. Then again, there were significant weight savings when Porsche evolved the Boxster into the Cayman, even though the engines are slighter different, so I still don't get it.

Btw, not saying you're not making sense. Chill dude.
 

Last edited by tranquility; 09-16-2007 at 05:31 AM.
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