Autobild on the 1 Series M Coupe - CF roof optional?

[1978.530i]

I want this car for so many reasons, but a difference in roof weight doesn't even make the top ten list. I'd like a convertible, but the coupe looks so much better, so I'm hoping for a sun-roof.

[silverfox]

This carbon fiber roof is more of a cool look than anything. I get the weight savings bit but give me a sun roof and larger turbos to compensate for the 44 lb add on. Give me 380 HP so I can get a 116 mph trap speed. Oh did I mention how crappy this 3 shade selection is. 50,000 car and the only true color option is orange. I' not buying a Chrysler product here. FN Orange Gimme a break!

[Yogijet]

Originally Posted by penny

Heck. Make A/C optional too. My windows are usually down to hear the exhaust anyways.

Me too, with the BMW PE, and I live in a dustbowl in the tropics!

[Pitkis]

Originally Posted by Kurt_OH

Not sure I agree.

There's nothing stopping a person from ordering a "base" M3 or 1M, then simply pulling the dash/rear or passenger seats/headliner/carpet/trim.

The fact is, almost NO ONE wants that, or they'd do what I said.

Well, that's true, but it's not so simple. CSL is quite hardcore but people are all the time asking for it. Making an own lightweight version is not difficult, but who wants to rape the car, throw away expensive electric seats and all add-ons installed by BMW and ruin resale value? Not very many, not even me yet. But getting a factory-built " very basic" version is totally the different thing and the way to keep your car's resale value in moderate level. I don't mean CSL now, just very simple version of basic car...

And to remember, this plan is reasonable only if you drive on track. I'v done somewhere around 700 laps in my M3 yet. Next season another 300-500 laps to come. There's no sense to modify road-drive cars like I described, but track driving is the different thing.

[Kurt_OH]

Originally Posted by Pitkis

Well, that's true, but it's not so simple. CSL is quite hardcore but people are all the time asking for it. Making an own lightweight version is not difficult, but who wants to rape the car, throw away expensive electric seats and all add-ons installed by BMW and ruin resale value? Not very many, not even me yet. But getting a factory-built " very basic" version is totally the different thing and the way to keep your car's resale value in moderate level. I don't mean CSL now, just very simple version of basic car...

And to remember, this plan is reasonable only if you drive on track. I'v done somewhere around 700 laps in my M3 yet. Next season another 300-500 laps to come. There's no sense to modify road-drive cars like I described, but track driving is the different thing.

Yea, we agree.

I bet a stripped out, track only special would be MORE expensive than taking the least-optioned street version and gutting it/setting it up for track though.

One last thing about CSL - if everyone who gets on a forum claiming they owned one, really did, there would be more of them than 335i! :-)

[Kurt_OH]

Originally Posted by formula M

Bro, your comments^ do not make sense, nor bolster or rebuttal anything.

Given these earlier comments of :"Good grief, my weight could change that much based upon the clothes I wear or how much I indulge over the weekend!"

Your weight is already below the center of gravity, even if you have a 40lbs brick in your shirt pocket, that weight is resting on your lower back and seat, thus it's weight is transfered there... even grade schooler understand this very simple concept... it seems you still don't!

Coincidentally, I was illustrating how erroneous your remarks were, as the over-all point was that top heavy is bad. And that center of gravity was the focus of the discussion (CF roof).

But, given your comments you don't seem to grasp this concept.

I understand your words; I don't agree with them.

Bottom line: those 8 lbs are IRRELEVANT. There's ZERO measurable performance difference, and WAY less difference than just the WEIGHT difference of various drivers, much less driving ability.

Again, keep it about the TOPIC, which is the roof, not about PEOPLE.

As I said before, I'd CONSIDER the roof, but wouldn't pay much for it. I like the look.

[EmmDrei]

If they will actually offer a cf roof option, I'd take it. Park a car with a cf roof in the sun and compare the temperature inside with one that has a steel roof and you'll understand why I like it. Yes, I love the looks too, but that is the main reason for me, why I'd want it again. As far as the "center of gravity" part of the discussion... bs. You'll never notice. I've driven M392 (with and without cf roofing) and M390 back to back. You'll notice, that the weight balance of the M390 is moved slightly to the front, but you can't feel a difference if you're in a car with a cf roof or not. I love looking at it and I like how it keeps the inside of the car cooler (imo, no scientific test undertaken) and... I don't like sunroofs anyhow. And since I'd stick cf on the outside and inside anyway, a cf roof would fit quite nicely. Do it, M GmbH! Please!

Peter

[Pitkis]

Originally Posted by Kurt_OH

Yea, we agree.

I bet a stripped out, track only special would be MORE expensive than taking the least-optioned street version and gutting it/setting it up for track though.

One last thing about CSL - if everyone who gets on a forum claiming they owned one, really did, there would be more of them than 335i! :-)

Sure, think about P911. GT3 is clearly more expensive. There's much more than stripping off in GT3, but anyway...

I'm afraid that F30 M3 won't get my vote in the first phase. My E92 has been great, driven over 60 000 km so far (only summertime). Best in the class and absolutely great machine. But give me one reason, why to upgrade? Ok, we haven't seen the car yet, but if we speak about street use, I have no idea why to upgrade to new one...but speaking about track use, there's a lot of potential to improve M3. If there comes next CSL, I'm sure it will catch many current M3 users upgrades instead of going to, say, 911. "Normal" M3 upgrade feels not to be a solution for many current E9xM3 drivers.

[EmmDrei]

Originally Posted by formula M

Therefore, I reject your (& others) mindless comments.

Honestly, "bro"... maybe you should stop talking and try driving a performance car instead. Reading car mags is one thing, being able to feel 5-10kg of weight being moved in a 1.500kg car is another. Get serious!

[Cameraeye]

Originally Posted by formula M

No, you're right... I see tons of DTM/ALMS cars with moonroof, because weight on the roof, doesn't matter.

Good Job!

[Evice]

Originally Posted by formula M

lulz...

Bro, its extremely odd (at this point in the discussion) that you still don't understand the concept of center of gravity in vehicles. Also, the actual weight removed, doesn't matter. It is WHERE it's removed from and that even 8lbs, on the very top of the car, once removed, lowers the over-all center of gravity of the car...

Coincidentally, that is why these companies spend BILLIONS in research and engineering, for lighter structural steel, nvh, stiffness, etc.


Therefore, I reject your (& others) mindless comments.

They don't reflect physics, nor reality. A Carbon Fiber roof is every bit of a performance option any other exotic structural material, or even a tail fin, etc.

Specially if you value very tossable cars. (ie: E30 M3/Taunus RS)




ps: (again) but it comes @ a premium.

I am 100% sure that if they let you drive 2 cars, exactly the same, one with CF roof and one with non-CF roof (so 8lbs. difference), there is NO WAY that you can understand the difference in public roads. Hell, even on track you will have absolutely no idea while the other parts of the car isn't 100% track ready.

Any car that is not prepped for track and with CF, is purely cosmetic in my opinion. Just think it this way. You have the damn back seats that's almost 50lbs and you are stuck with that 8 lbs difference? and if you wanna talk physics, 8 lbs on the top of the car vs. 50 lbs at the mid height of the car, in a sweeper turn will create roughly the same amount of body roll due to it is torquing vs. level length.

In addition, you are giving examples from DTM/ALMS cars, which are RACE cars, stripped down to the max where there is no weight to shave off. YES THEN the damn roof will be a weight savings and very important.

So in my opinion, all of your crying and moaning is quite pointless unless you wanna cry about why they give you back seats as well. MOOT MOOT MOOT.

[Haywood]

Adding more fuel...

http://www.topgear.com/uk/james-may/...bre-2007-12-01

[amalgamman]

Originally Posted by formula M

Your statement is illogical.

Your saying weight matters, but not in this instance, because it's only 8lbs (or whatever it may be).

So which is it..? Weight matters, or it doesn't..



Secondly, "cosmetic" implies it purely aesthetic & doesn't save weight... which we both know CF roof do. Perhaps you're trying to say you don't find any value in a CF roof..?

The point he is trying to make is that 8lbs extra on the roof will not make much difference at all on how the car handles, and I tend to agree.

I'd like the CF roof, it would look great but I'm not expecting that it will make the car corner any better.

[EmmDrei]

Originally Posted by formula M

No, you're right... I see tons of DTM/ALMS cars with moonroof, because weight on the roof, doesn't matter.

Good Job!

Honestly... if you don't know, what you're talking about, don't make yourself look worse! Fact is, you know nothing about racing.

The DTM does not allow carbon roofs (See DTM rules & regs Art. 5.0.1 - only available in German). Neither does the ALMS, unless the homologated serial car has a cf roof. Both the DTM, as well as the ACO (which is actually the governing body that set's the rules & regs for the GT1, GT2 and GT3) require rescue hatches (through which a driver can be rescued while strapped into his/her seat) in a cars roof and these can be made from cf. The form and size of these hatches are pre-defined.

Besides... I did not write it doesn't matter. I wrote, that you (and I) will not feel the difference, because of the ratio of that weight in comparison to the cars total weight. Do you know how much weight where influences a cars track time? Ever actually balanced and set up a race car? No. So please just stop going on about stuff you know absolutely nothing about. Thanks!

[JB135MDCT]

CF does matter, but it is to small to detect as a singular difference. Every time you decrease weight of the car, it will lower the center of gravity. In terms of 8lbs, the percent difference is to small for you to detect.

A sunroof is a deal breaker for me. If I have to pay some ridicules price for CF, I will, but only to not get a sunroof.

NO M car should have a sunroof, it is the GAY.

[EmmDrei]

Sorry, I give up. I am not sure if your problem is reading or understanding. You can probably find someone to read texts to you. Having someone interpret and explain them, may be a little more expensive. But it may be worth a try.

[niuniu]

Guys you're all saying the same thing - that removing 8lbs does make the car lighter. And in theory on some scale of measurement that that should make the car faster, but just that in normal road going conditions and actual noticeable performance you won't feel it, because it's only 8lbs.

[Kurt_OH]

Originally Posted by niuniu

Guys you're all saying the same thing - that removing 8lbs does make the car lighter. And in theory on some scale of measurement that that should make the car faster, but just that in normal road going conditions and actual noticeable performance you won't feel it, because it's only 8lbs.

Yup, that's right. You won't feel it, can't measure it via vehicle performance: it doesn't matter.

[therealm3]

Originally Posted by niuniu

Guys you're all saying the same thing - that removing 8lbs does make the car lighter. And in theory on some scale of measurement that that should make the car faster, but just that in normal road going conditions and actual noticeable performance you won't feel it, because it's only 8lbs.

Sorry guys, but I am going to have to chime in here. If you are a half way decent driver you will notice the difference. On my E30 M3, using a slightly different motor mount which lowers the motor by 1/4 of an inch from stock, makes a perceptible difference in handling of the car. Yes, only 1/4 OF AN INCH. It turns in more precisely/quickly and feels more nimble on its feet. I wasn’t a believer till I tried it. And now that did not remove any weight at all, just moved the center of gravity down a smidge. In other words the same effect as taking 8 or 44 lbs off the roof. If all you do is drag race or stop light race, then yes the roof will make little to no difference, but in terms of handling it does matter.

And BMW please make a blue for this car so I will have no reason not to buy.....

[niuniu]

Originally Posted by therealm3

Sorry guys, but I am going to have to chime in here. If you are a half way decent driver you will notice the difference. On my E30 M3, using a slightly different motor mount which lowers the motor by 1/4 of an inch from stock, makes a perceptible difference in handling of the car. Yes, only 1/4 OF AN INCH. It turns in more precisely/quickly and feels more nimble on its feet. I wasn’t a believer till I tried it. And now that did not remove any weight at all, just moved the center of gravity down a smidge. In other words the same effect as taking 8 or 44 lbs off the roof. If all you do is drag race or stop light race, then yes the roof will make little to no difference, but in terms of handling it does matter.

And BMW please make a blue for this car so I will have no reason not to buy.....

Moving 500lbs (engine weight) or so 1/4 of an inch is a big deal! How can you compare that to removing 8lbs I have no idea.

[HBspeed]

Originally Posted by therealm3

Sorry guys, but I am going to have to chime in here. If you are a half way decent driver you will notice the difference. On my E30 M3, using a slightly different motor mount which lowers the motor by 1/4 of an inch from stock, makes a perceptible difference in handling of the car. Yes, only 1/4 OF AN INCH. It turns in more precisely/quickly and feels more nimble on its feet. I wasn’t a believer till I tried it. And now that did not remove any weight at all, just moved the center of gravity down a smidge. In other words the same effect as taking 8 or 44 lbs off the roof. If all you do is drag race or stop light race, then yes the roof will make little to no difference, but in terms of handling it does matter.

And BMW please make a blue for this car so I will have no reason not to buy.....

+1 on everything you said.

Especially needing a BLUE!

[Kurt_OH]

Originally Posted by niuniu

Moving 500lbs (engine weight) or so 1/4 of an inch is a big deal! How can you compare that to removing 8lbs I have no idea.

Actually I'm certain it CAN be compared, in at least 2 ways:

1. Test it. Put the cars on a track and see what happens.

2. Calculate it. How much difference in the angular momentum is generated by each change (steel w/sunroof, steel w/o sunroof, CFRP w/o sunroof).

So far, no one here has done either, which means it's ALL a bunch of hot air and nothing else, from both opinion perspectives. Yea, that includes my own - the "8lbs is a meaningless change" opinion.