M Roadster Roll Bar Options?

[AllThingsGhetto]

I was skimming through the threads and saw various harness/roll bar options for the coupes. Are there any 4 point options for the Roadsters while being able to keep the hardtop? I've searched various boards and even *cringe* Ebay, but none to my finding that would be functional.

Any help pointing me in the right direction is greatly appreciated.

[gmushial]

You might see if a HardDog rollbar would meet your needs.

[fuz9]

Back when I had my roadster I wanted to get a Hard Dog bar in polished finish and then mount a fire extinguisher to it. It would have looked epic commuting to work

http://forums.bimmerforums.com/forum...-Roadster-Pics

[AllThingsGhetto]

That Hard Dog roll bar is pretty sweet. I'm reading that it will not work with the hardtop. I'm intending on keeping the hardtop on the vehicle and was interested in one that would work with it. Of course, I'd remove it to fit it on, but clearance issues are what worry me.

[Gregor54]

Pretty much all race shops will fabricate a bar to any spec. Forget the tuner places. You need a shop that builds race cars. Will be more money, but they can build you exactly what you want. One thing to watch is that most clubs require the so called broom test, i.e. they need to be able to put a broom on the top of the windshield and have it clear the top of your helmet. So, if you make the bar too low, it may not be high enough to pass muster. I have seen people slant their seats back a bit to gain a bit of clearance, but...

Also, typically the bars mount to the shock strut towers, so to change the shock mounts, you typically need to remove the bar. Accordingly, a removable link piece which can be removed without taking out the entire bar will save huge headaches later on. And, finally, there should be plates under the car to reinforce the mounting points for the roll bar. If you are going to do belts, you should be thinking about it now. Not a really good solution with the stock seats for the groin belt as many clubs are unhappy with them going around the front of the seat. I have cut-outs in my seat backs that take the belts to the cross bar on the roll bar. These are all things a good race shop will know. Find someone good, and then you can see if it is feasible. Watch what it will cost, as mine was not cheap by time it was all in.

[AllThingsGhetto]

Thank you very much for your reply. I actually just contacted a local shop near me that participates in various race events, etc. Cost for a chromoly cage would be about a grand. I'm still doing my research as I definitely want the form and function on this if I'm going to spend the money.

[328 Power 04]

I have the Hard Dog roll bar with cross member on the white Z3. It will not fit hard tops. With slight modification you can get it to clear the power top. Looks amazing, and is extremely solid.

[gmushial]

I have the Hard Dog roll bar with cross member on the white Z3. It will not fit hard tops. With slight modification you can get it to clear the power top. Looks amazing, and is extremely solid.

Care to elucidate w/re slight modification? Likewise, any sense of added stiffness to the roady?

[z3papa]

Care to elucidate w/re slight modification? Likewise, any sense of added stiffness to the roady?

You have to notch the backing plate which is not really recommended by Hard Dog. Good news is the bar is made with such strict tolerances, if your car is tweaked at all, it takes a whole lot of persuasion to get it in which means it will take and more to get it out of your car making it stable regardless. It definitely stiffens up the chassis of the car.

[328 Power 04]

You have to notch the backing plate which is not really recommended by Hard Dog. Good news is the bar is made with such strict tolerances, if your car is tweaked at all, it takes a whole lot of persuasion to get it in which means it will take and more to get it out of your car making it stable regardless. It definitely stiffens up the chassis of the car.

Haha, so true, I had beat it in a little too deep, but I wanted to provide maximum height without interfering with the top, so then I attached it to a machine shop crane with straps, and lifted it while hitting it with a rubber mallet... could have lifted the whole car up, and it wasn't bolted in at all. It wouldn't budge, now the top's headliner just very gently rubs past it. Just perfect. I doubt it would be easy to remove from the car though.


You have to create a channel in the left side of the backing plate for the hydraulic piston from the top to clear. It will not reduce its strength as long as you don't go crazy with the cutting.

[gmushial]

Haha, so true, I had beat it in a little too deep, but I wanted to provide maximum height without interfering with the top, so then I attached it to a machine shop crane with straps, and lifted it while hitting it with a rubber mallet... could have lifted the whole car up, and it wasn't bolted in at all. It wouldn't budge, now the top's headliner just very gently rubs past it. Just perfect. I doubt it would be easy to remove from the car though.


You have to create a channel in the left side of the backing plate for the hydraulic piston from the top to clear. It will not reduce its strength as long as you don't go crazy with the cutting.

I have this image of the Z hanging by the HardDog... and not letting go :-) W/re the top: if one converts it back to manual top, then this isn't a problem?

- - - Updated - - -

You have to notch the backing plate which is not really recommended by Hard Dog. Good news is the bar is made with such strict tolerances, if your car is tweaked at all, it takes a whole lot of persuasion to get it in which means it will take and more to get it out of your car making it stable regardless. It definitely stiffens up the chassis of the car.

Seriously sounds like a recommendation - thanks, as always.

[Coldaccord]

Haven't been able to find any straight side profile shots of the bar. Curious if it will clear my helmet, I'm 5'11" so not too tall.

I don't mind getting fixed back seats to lower my driving position

Would like to be able to pass tech for track days

[Vintage42]

Haven't been able to find any straight side profile shots of the bar. Curious if it will clear my helmet, I'm 5'11" so not too tall...

If you google hard dog roll bar bmw z3, there's a lot of photos, some of which seem to answer your question.