here's a good question RE: the new Z4

[z4M]

here's a good question RE: the new Z4
does it have 50/50 weight distribution with the steel hard top up? or down?

hmmmm

I guess the best alternative gets a bit 'philosophical'....

[scottpettit]

[tom_m]

...the center of gravity will definitely be lower with the top down.

That might make more difference than the F/R distribution.

Tom M.<img src="http://members.roadfly.org/tom_m/high_voltage_sign_spinout_md_wht_17652.gif" height=120 width=120>

"All of us get lost in the darkness
Dreamers learn to steer by the stars
All of us do time in the gutter
Dreamers turn to look at the cars" - N. Peart

[scottpettit]

Here is what my contact in Germany has sent:

"'we don't have communication numbers for the weight distribution with the roof down as this isn't required for the homologation. But for your information: there is almost no difference between the roof up or down as almost all parts stay in about the same longitudinal position - the only part of the roof that changes place is the part over the drivers head.

In spite of this the little bit of weight that changes backwards is positive for the acceleration numbers."

As I get more info, I will post it here.

Scott Pettit
President
BMW-ZSCCA

[2zero]

What kind of answer is that??

That's BS!!!

It's a 200LB piece of steel it has to make a huge difference.

They didn't want to move the battery out the trunk to keep the weight distribution even.
Now they say it's not an issue!!

[rustyh]

No disrespect to Mr. Pettit, and I certainly have no clue who is "contact" may be, but from an engineering perspective that's just not how it works. Sounds more like someone trying to make an intelligent comment based on a novice's observation of what happens when the top lowers. I suppose there could have been some confusion depending on how the question was posed to this person, but if BMW has managed to keep the weight distribution the same either way, I'm sure a whole lot of other car companies, aircraft companies, NASA, etc would love to know how. lol

I wouldn't go so far as to say you're shifting 200 lbs of sheet metal one direction. That's not likely what's happening either. Some pieces move one way, others move another. But it's not going to balance out exactly.

Mr. Pettit, does this "contact" purportedly work for BMW or is this just someone that happens to live in Germany (and may/may not) actually own a BMW? :-) (just kidding...no offense)

Scott

[\]

[z4M]

[2zero]

200 lbs I was being sarcastic!!
The top can't weight 200LBs but it certainly weighs more than a battery!!

[scottpettit]

[scottpettit]

Regensburg.

I don't know if New Jersey is filtering the info but what they tell me I pass on to you.

In regards to who my contact is, you can't get much higher.

By the way, there will be 3 new Z4's at [Oops!] and BMW has asked me if I will be there. Unfortunately I cannot go due to as I just returned from the OBX CruiZe in North Carolina and I need to work this weekend. If anyone on this forum goes, please get some answers.

Scott Pettit