No Need to Fear the Front Bumper Scrape - 2015 BMW M235i Convertible Long-Term Road Test

Edmunds.com

No Need to Fear the Front Bumper Scrape - 2015 BMW M235i Convertible Long-Term Road Test

Just because our long-term 2015 BMW M235i is a sporty coupe, doesn't mean it has to scrape on driveways and parking barriers

Read the full story here

daryleason

Which just goes to show that either A) BMW is willing to sacrifice fuel economy for practicality in some areas, or they came up with a way to channel the air to where the higher front fascia clearance didn't negatively impact fuel economy.

What I'm waiting for is a car company to combine accident avoidance sensors with a powered front airdam than raise & lower itself electronically while at higher speeds to reduce airflow as much as possible, but still prevent damages. We know cars already have powered rear diffusers/wings, such as the Porshe 911 & Chrysler Crossfire. Now, with the larger implementation of the radar/sonar/laser/magic of adaptive cruise control, you wouldn't think it'd be too hard to write a computer algorithm to that could also scan ahead to adjust a front splitter's height to avoid upcoming obstacles at speed, maybe also include a requirement that it doesn't lower into place until you hit 40 mph.

mercedesfan

@daryleason,

The Porsche 911 Turbo actually does have an adjustable front air dam. It retracts into the bumper at low speeds to prevent impacts, but at 75mph it activates to increase down force on the front axle.

daryleason

@mercedesfan : So it sounds like Porshe is part way there. It's speed-dependent, but if you come up on something in the road (like a sharp dip or incline) it stays in the same position, correct?

opfreak

It will scrape. I know first hand.

mercedesfan

@daryleason,

Well yeah, if you hit something at 75mph it will definitely scrape. Then again, you are in bad shape anyway if you hit debris or a big dip at that speed!

daryleason

@mercedesfan : What you said is true...but what I'm actually thinking of is this. With a normal front air splitter, it's normally just mounted with those plastic tab/screws. If it gets ripped off, you either go back for it, or buy a new one, then pop in some new plastic whatevers, and you're typically good to go. However, when you add in the whole "raise/lower" aspect, now you're talking about some sort of electric motor, an armature or screw system setup, possibly a frame-track. I'm wondering about the aftermath of an impact with it.

opfreak

mercedesfan said:

@daryleason,

Well yeah, if you hit something at 75mph it will definitely scrape. Then again, you are in bad shape anyway if you hit debris or a big dip at that speed!

the wheel stops in the edmunds example are short. While the m235 bumper is not extermly low, its still far lower then most cars, and if there is a decent size wheel stop, or regular size curb (that a standard car would clear). The m235 wont.

longtimelurker

Those parking blocks are relics of another automotive age...before cars had air dams to improve fuel economy and performance in windy conditions, to prevent air from getting under the car.

Most people with modern cars understand by now that you can't pull into a parking space until your front tires hit the parking block, because you'll damage the car. You should not have to use that block as a means of telling where your front - or rear - tires are...you're supposed to be able to tell just by having...I dunno - driving ability - ?

tlangness

Look at the picture again lurker. See any tires touching the block? The ability to pull further forward gets the tail end in line with other cars in the parking lot. It's the courteous thing to do, with... I dunno - driving ability - ?

What's more, the parking blocks help SUVs, Trucks, and other high-riding vehicles from parking with their nose over the curb and getting in the way of foot traffic. The also help avoid curb damage and are generally useful at keeping cars from mounting the curb and hitting the building.

longtimelurker

tlangness said:

Look at the picture again lurker. See any tires touching the block? The ability to pull further forward gets the tail end in line with other cars in the parking lot. It's the courteous thing to do, with... I dunno - driving ability - ?

What's more, the parking blocks help SUVs, Trucks, and other high-riding vehicles from parking with their nose over the curb and getting in the way of foot traffic. The also help avoid curb damage and are generally useful at keeping cars from mounting the curb and hitting the building.

Wait - I was not casting aspersions on YOUR driving ability - just saying that the idea of using these blocks to do all of the things you're talking about here is no substitute for actually knowing where one's car is within the parking space. That's all.

The fact that many cars can pull forward over the block and many cannot, coupled with the great disparity in car, truck and SUV lengths, coupled with varying block heights, means there's very little chance that the tail ends of cars are going to line up in any event.

In most of the car-hits-building instances I see, the presence or absence of a parking block was a minor factor.