SEMA 2015 - Bulletproof Automotive ditches the folding hardtop and windshield for a very unique E89 Z4

[Sticky]

This Z4 easily stood out at the 2015 SEMA show. The most obvious change made by Bulletproof Automotive is that the folding hardtop is gone. The car is now a dedicated roadster offering design somewhat reminiscent of a Porsche Boxster Spyder.

Seeing it in person of course allows one to pick up on all the little details such as the side exit exhaust cut out from the passenger side front fenders. This changes the look of the rear as well as they go with an aggressive carbon rear diffuser without worrying about room for any exhaust pipes or tips.

Carbon accents abound such as in the large rear wing along with the sideskirts and front diffuser. These pieces integrate well with the widebody setup which is clean and molded well. Liberty Walk bolted on pieces with gaps this is not.

Unfortunately further details on the build were not presented with the car. It is somewhat of a shame something like this was just left in a booth without any details. How much weight did they save taking out the folding hardtop and windshield? Did they actually test the aerodynamics? Is this all just for show or is this designed to allow for wider tires and more downforce to hit the track?

Either way it's awesome and well done inside and out with a ton of effort going into this build.

#SEMA2015

[G0TB00ST?]

sooooo it looks fast, but is it all show or is there some go too?

[Sticky]

sooooo it looks fast, but is it all show or is there some go too?

That's a good question I wish I had an answer to.

[ope92]

At the very least it should be a fbo car, and assuming they reduced the weight significantly (hard top is about 400lbs on an e93) car should be quick around a road course. Also the side exhaust is saving quite a bit of weight

[The Convert]

Honestly...looks a little ricey to me. Sorry, but possible performance aside, I just can't get onboard with this thing.

[Tony@VargasTurboTech]

Honestly...looks a little ricey to me. Sorry, but possible performance aside, I just can't get onboard with this thing.

Saw it in person, in my eyes is an abomination. It was the epitome of rice.

[G0TB00ST?]

At the very least it should be a fbo car, and assuming they reduced the weight significantly (hard top is about 400lbs on an e93) car should be quick around a road course. Also the side exhaust is saving quite a bit of weight

im sure they dropped a significant amount of weight, but that's a lot of body work. I'm sure all those panels, wings, and reinforcement probably put the weight back close to stock.

[Sticky]

Honestly...looks a little ricey to me. Sorry, but possible performance aside, I just can't get onboard with this thing.

I don't consider it rice the way I do some of the Liberty Walks garbage I saw.

This actually took some creativity and skill.

It's different but not modded in a cheap Asian style. The bodywork was perfect and the side exhaust might save some weight.

Ditching the folding top is a smart idea to shave weight as well.

There's definitely some major performance benefits to the choices here which by definition is not form over function.

[The Convert]

I don't consider it rice the way I do some of the Liberty Walks garbage I saw.

This actually took some creativity and skill.

It's different but not modded in a cheap Asian style. The bodywork was perfect and the side exhaust might save some weight.

Ditching the folding top is a smart idea to shave weight as well.

There's definitely some major performance benefits to the choices here which by definition is not form over function.

Meh. The lack of a front windscreen would have to kill the aero and there would be no reason to have a huge wing with the airstream now being so much lower due to the lack of a roof. I just think it looks tacky and more idealized than practical aero wise.

[Sticky]

Meh. The lack of a front windscreen would have to kill the aero and there would be no reason to have a huge wing with the airstream now being so much lower due to the lack of a roof. I just think it looks tacky and more idealized than practical aero wise.

It's a good question regarding the aerodynamics but I'm pointing out there are performance benefits to the mods done namely in the weight saving game.

It's different and that's good unlike the LB stuff which is the same everywhere and offers no performance benefit.

[The Convert]

It's a good question regarding the aerodynamics but I'm pointing out there are performance benefits to the mods done namely in the weight saving game.

It's different and that's good unlike the LB stuff which is the same everywhere and offers no performance benefit.

The weight savings of the retractable hardtop is indisputably good. Reducing exhaust weight is not necessarily good in my opinion. You're reducing weight from the bottom of the car which raises the roll center slightly. For a road course car, less benefit than a strip car.

I I don't agree that the LB kits provide no performance. They open the arches for more meat, and that is a performance upgrade.

[Sticky]

You're reducing weight from the bottom of the car which raises the roll center slightly. For a road course car, less benefit than a strip car.

The center of gravity is already tremendously reduced to such a degree that the exhaust change is negligible when it comes to that.

They open the arches for more meat, and that is a performance upgrade.

Seems like we see the arches opened more for 21's and not for 345's. And what is the effect on drag? To me LB is all style over substance. Is anyone really buying the kit for road racing?