[SeanJP]

Does anyone know how much weight is saved if you forego the moonroof on an M240i? Google gets me inconsistent answers, and none from primary sources. Here is an interesting thing I found. If you “build your own” M2 on the BMW website, BMW claims the M Carbon Roof option only reduces weight by 48 pounds. That’s 48 pounds with using carbon fiber and deleting the moon roof: “Enhance driving dynamics by lowering your vehicle's center of gravity and reducing the overall weight by 48 pounds with a sleek, contrasting roof made from carbon fiber reinforced plastic (CFRP). Important: This option will remove the standard moonroof.”

This seems to suggest removing the moonroof (by itself) reduces very little.

Also, what are other weight savings that could be had? For example, I’m going to leave off the “lumbar support” seats. I actually don’t care for electric seats with a dozen buttons.

[Pentland]

There was a recent thread on this. It’s about 15kg.


Ps don’t get hung up on vehicles weight. If you want to reduce the vehicle weight, look at the nut on the drivers first.

[SeanJP]

Originally Posted by Pentland

There was a recent thread on this. It’s about 15kg.


Ps don’t get hung up on vehicles weight. If you want to reduce the vehicle weight, look at the nut on the drivers first.

It’s going to be a fun weekend car that I occasionally take to the drag strip. While I don’t obsess over every little pound, weight matters to me. If I can get a substantive amount of weight reduced by foregoing options I can live without, I’ll do it.

[Pentland]

Originally Posted by SeanJP

It’s going to be a fun weekend car that I occasionally take to the drag strip. While I don’t obsess over every little pound, weight matters to me. If I can get a substantive amount of weight reduced by foregoing options I can live without, I’ll do it.

In that case, not only would I not option the sunroof, I wouldn’t option the M240i.

[SeanJP]

Originally Posted by Pentland

In that case, not only would I not option the sunroof, I wouldn’t option the M240i.

Why?

[Pentland]

Originally Posted by SeanJP

Why?

Because cars like Caterham’s and Lotus Emera exist.

[SeanJP]

Originally Posted by Pentland

Because cars like Caterham’s and Lotus Emera exist.

Not what I’m looking for my weekend car. A 240i xDrive gives me the luxury, beauty, and other attributes I’m looking for in a weekend fun car. With a few mods It will do plenty well at the drag strip. Hell, even stock it puts up respectable numbers.

[Dinosoar]

To me, weight is the most important design feature to a sports car. It improves all three dynamics of a car's performance. Makes it easier to have a stable car too.

I agree, one cannot obsess about it for a street car, but it is a paramount factor. Of course, so many cars, BMW included, have gotten so heavy, seems a moot point half the time. But for me, I will be optioning my M240 with no moon roof, RWD only, and replace the wheels with forged wheels.

[SeanJP]

Originally Posted by Dinosoar

To me, weight is the most important design feature to a sports car. It improves all three dynamics of a car's performance. Makes it easier to have a stable car too.

I agree, one cannot obsess about it for a street car, but it is a paramount factor. Of course, so many cars, BMW included, have gotten so heavy, seems a moot point half the time. But for me, I will be optioning my M240 with no moon roof, RWD only, and replace the wheels with forged wheels.

I agree that it’s a critical factor, hence my OP question. And you’re right, all cars seem to be steadily gaining weight over time. A drag race is mostly power to weight ratio + traction. Getting a good launch is huge, so IMO the benefits of AWD outweigh (pun intended) the cons. If it was a single purpose drag vehicle I am after, a BMW would be entirely the wrong choice. And also for a single purpose vehicle, you can make up for not having AWD with things like having smaller wheels, and big drag tires in the rear. AWD allows me to get lots of traction without having to sacrifice any of the driving dynamics for its “weekend fun car” duties.

[Dinosoar]

Originally Posted by SeanJP

I agree that it’s a critical factor, hence my OP question. And you’re right, all cars seem to be steadily gaining weight over time. A drag race is mostly power to weight ratio + traction. Getting a good launch is huge, so IMO the benefits of AWD outweigh (pun intended) the cons. If it was a single purpose drag vehicle I am after, a BMW would be entirely the wrong choice. And also for a single purpose vehicle, you can make up for not having AWD with things like having smaller wheels, and big drag tires in the rear. AWD allows me to get lots of traction without having to sacrifice any of the driving dynamics for its “weekend fun car” duties.

I hear you. I'm a road racer, so I am far more into a balanced vehicle and generally don't want AWD.

Are you allowed to use launch control at the drag strip...spooling up the BMW turbo is key...and an XDrive M4 may be the ticket...such a damn quick car!! I know that's a very different budget tho.

[SeanJP]

Originally Posted by Dinosoar

I hear you. I'm a road racer, so I am far more into a balanced vehicle and generally don't want AWD.

Are you allowed to use launch control at the drag strip...spooling up the BMW turbo is key...and an XDrive M4 may be the ticket...such a damn quick car!! I know that's a very different budget tho.

Yep, you see cars revving and spooling up all the time at the start line. You’ll see every manner of pre-race prep, including nitrous guys purging their lines. They have a burnout box too for those who want to clean and heat their tires just before getting on the line.

My last toy car was a heavily modified Challenger making 671 to the wheels. Whenever I lined up against guys with AWD, they would leap off the line, way out in front every single time. Most of the time I would reel them back in, but not always.

[SeanJP]

One other thing, drag strips are welcoming to everyone. You’ll see everything from drag only trailer queens ruining 8’s, to 16 second Honda Civics, and everyone is cool with each other. I’m sure you know this, but it’s not at all like the “you owe me a 10 second car” F&F macho culture like in the movies. If you’re running bad times, no one is going to care or even notice. They’ll even give you pointers if you ask.

[RockCrusher]

Originally Posted by Pentland

There was a recent thread on this. It’s about 15kg.


Ps don’t get hung up on vehicles weight. If you want to reduce the vehicle weight, look at the nut on the drivers first.

It is about 15kg but it removes this weight from very high up which helps lower center of gravity.

I've never driven an M2 with a moon roof so I have nothing to compare my M2 with its CF roof to.

But I owned a Scat Pack, then a Hellcat, then a 2nd Scat Pack. All 3 had moon roofs. But the Scat Pack didn't have a supercharger on top of the engine.

In the Scat Pack, the 2nd Scat Pack (after owning the Hellcat for 33 months and putting around 27K miles on the car) I could feel the difference in weight -- ~200lbs less than the Hellcat -- but I could really feel the difference with the car's lower center of gravity.