BMW M3 / M4 - Smartly Light, Rigid, Precise: Deep Dive and Interview

[bradleyland]

Originally Posted by Cuz5150

^^^this^^^

Is this the reason why its made out of steel?
I myself find it odd, that in 2014 BMW is not making rear sub-frames out of Aluminium As far as i know, no other manufacture is rocking this set up. Its either expensive chunk of Aluminium or hard to mold, weld together

The interview says it's a space consideration:

... the rear one is made of steel; there wouldn't have been enough space available for an aluminium construction.

Aluminum, being a weaker raw material than steel, requires more material to deliver the same strength.

[TankerJoe]

It was amazing to watch the production of M3 and M4 cars on the same line as the 3 and 4 series and X3 vehicles in Munich yesterday. Though the Mcars share many of the same components as their brother models, BMW is extremely meticulous to ensure that specialized M parts go onto Mcars. If you've never been to a BMW plant tour, it's well worth it. I am now a true believer in the quality that goes into the BMW vehicle.

[rick berry]

Excellent interview. The level of technical information and the thought that goes into M cars is impressive. Thanks Jason for another gem!

[Jockey]

So some people don't think this car is an engineering feat, ok..

[tooch]

Great read. My first M , can't wait....

[amzbimmer]

That technology is progressing, and machines can multitask better.

[Miko M3]

All this articles that I am reading just drives me crazy. Can't wait to drive it!! 5 more weeks.

[khanyam4]

[jonasaurus]

[Saphirschwarz]

i need that roof

[4er_Meister]

I cannot wait to get my hands on one of these!!

[JoeFromPA]

I thought it was interesting too that the rear subframe being made out of steel was considerered acceptable because:

1. It cut costs (which can be used elsewhere)
2. It required less space due to steel needing less material for a given strength rating compared to aluminum.
3. It wasn't deemed as important there anyway due to it keeping the weight low and to the rear - a valid point.

[G80indy]

I wonder how extensive damage would be/result by hitting a curb hard, for example...
Wheel to Suspension to Frame etc etc

[bradleyland]

Originally Posted by 330indy

I wonder how extensive damage would be/result by hitting a curb hard, for example...
Wheel to Suspension to Frame etc etc

Don't hit curbs

[G80indy]

Originally Posted by bradleyland

Don't hit curbs

Don't intend to.
Wondering if it will drive up my insurance!

[bradleyland]

Originally Posted by 330indy

Don't intend to.
Wondering if it will drive up my insurance!

In all seriousness, it is a valid concern. A suspension without any bushings -- from a pure engineering perspective -- is more likely to be damaged in an accident, but only slightly.

Having a vehicle totaled because of suspension impact damage is like playing the lottery. The lack of bushings increases the energy that will transfer to the chassis, but the line between damage and no-damage is very thin. Basically, if you hit something hard enough to damage a non-bushing chassis, there's a very, very good chance it was strong enough to damage a bushing chassis too.

[Kef9]

Sorry for the thread bump but it’s crazy to think looking back at this and the weight saving measures applied to the F80 and comparing it to what happened with the G80. Where is this information and explanation for the latest vehicle?

[M3SQRD]

Originally Posted by Kef9

Sorry for the thread bump but it’s crazy to think looking back at this and the weight saving measures applied to the F80 and comparing it to what happened with the G80. Where is this information and explanation for the latest vehicle?

When you keep increasing power/torque, adding AWD, increasing size…the mass will continue to increase. The e46 M3 was the perfect size M3 and if you wanted a bigger car then you’d buy a M5. Current M3/4 is the size of a 5 series from a decade ago.

[dezzracer]

Originally Posted by JustChris

Love it.

You just KNOW this has been thought through so well. Lightweight application is the future and BMW is right in the leading pack.

You mean like the 5300 lb G90 M5 hybrid pig coming in 2025? 1700 lbs more than my F80. Leading the pack is right.

[JustChris]

Originally Posted by dezzracer

You mean like the 5300 lb G90 M5 hybrid pig coming in 2025? 1700 lbs more than my F80. Leading the pack is right.

Indeed. They were trying with the F8X, with the CF driveshaft, bootie etc but now sheesh they’re just bloated beyond belief and it’s all about the luxo HP wars.

Whatever happened to carbon core cars that were trumpeted with 7 series launch and such. Lost it to some degree….yet sales are better than ever.

[Kef9]

Exactly. It’s perplexing to me. I’m just done with the latest cars really with all the tech I don’t want and the screens which will all date really badly. I don’t do many miles so I’m hoping my F80 and F87 do me for as long as possible.