MPG difference between Coupe and Roadster?
- Thread starter Breaker
- Start date
As a discussion sub-topic, I would think that a roadster with a wind screen in place has less drag then one without. And as far as coupes (Si) and air conditioners go...they're electric so we don't need to roll with the windows down. 
Even so, because its a roadster it would still need a more sturdy chassis adding weight. But for the coupe it wouldnt thus being lighter and better mpg.
This is unless BMW use exactly the same chassis for the roadster and coupe. If this is the case then the coupe would be much heavier (as it has a hard roof) which would mean the roadster should have a better mpg…
This is unless BMW use exactly the same chassis for the roadster and coupe. If this is the case then the coupe would be much heavier (as it has a hard roof) which would mean the roadster should have a better mpg…
M Roadster is 1485kg and M Coupe is 1495kg.
As has been mentioned the Z4 was designed as a roadster from the outset with the Coupe coming along as an "afer thought" hence no additional stiffening required like on most cars which are designed as a Coupe initially eg 350Z.
MPG who cares? If i was bothered about economy i wouldnt be buying an M car.
As has been mentioned the Z4 was designed as a roadster from the outset with the Coupe coming along as an "afer thought" hence no additional stiffening required like on most cars which are designed as a Coupe initially eg 350Z.
MPG who cares? If i was bothered about economy i wouldnt be buying an M car.
Gave BMW a chance to improve on the initial concept.pvr said:Love the "after thought" bit
pvr said:Incompatible said:Gave BMW a chance to improve on the initial concept.pvr said:Love the "after thought" bit
Last time, Frankenstein was created as an afterthought
Breaker said:pvr said:jokuhl said:I am a roadster girl .....we are such nice people too!
So .. are you saying that Coupe drivers are not nice people?
No, she's saying roadster drivers are girls!
Bit of fun!
Back to topic, I can't find anything on the net about this either as far as MPG goes. What about performance with the roof up or down?
(Bored at work!!)
Not quite the same thing but Alpina quote a top speed for Roadster S of 265kmh with the roof up and 270kmh with the hardtop fitted, gives you an idea of the difference the aerodynamics make. I guess putting the roof down would lose another 5 - 10 kmh.
reading this thread is so much fun, hahaha :lol:
2 things
1. if you are driving at 70 mph for an extended period of time, would you really be driving top down? some would, some wouldn't
2. if you are worried about fuel economy at 70 mph, wouldn't you just put the top up? therefore, the roady might be better on fuel since it is 10kg lighter
not that i'm saying there is anything wrong w/ the coupe
2 things
1. if you are driving at 70 mph for an extended period of time, would you really be driving top down? some would, some wouldn't
2. if you are worried about fuel economy at 70 mph, wouldn't you just put the top up? therefore, the roady might be better on fuel since it is 10kg lighter
not that i'm saying there is anything wrong w/ the coupe
But of course....what's a friend for? (Yes, it's a guy thing.)chetalien said: