Roll Over Protection discussion

[93_Clubman]

There is also a pic around (on this forum or its predecessor) of an SP that rolled up in NE NSW somewhere(I think).

Think this is the one you're refering to GM:

silverspforumsizexi8 (3).jpg

[greenMachine]

Yes that is it.

Thanks for posting.

[Gdekwant]

On the note of head clearance, from what I have been reading on the forum and around the internet it seems that the BD bar and the MX5+ bar both sacrifice some height in favour of being able to fit a hardtop to the vehicle? If this is the case is there some validity in getting a rollbar made that sits higher but will only accommodate a soft top?

Also in terms of head clearance, mounting a seat directly to the floor of the car is obviously the easiest way to mount it the lowest, but does anyone know what certain models of seat may be the thinnest/lowest or whatever term you prefer and hence provide sufficient clearance?

I've tried looking around alot and get an answer of, maybe and no idea for the above questions. Only reason I ask is I am 6'2" and intend on tracking the car, and whilst it is somewhat unnecessary, I do prefer to take precautions for my own safety.

Thanks in advance.

[Guran]

My BD rollbar touches both my softtop and hardtop. The rollbar could not be any higher without restricting the use of both tops. I have a race seat which is mounted on stock rails. There are seats that can sit lower, but I haven't been forced to go looking (yet). With what I have, and at my height of 5'6", my helmet is less than 50mm below the top of the rollbar. It's close though - about another 20mm would probably do it. In any case, it doesn't matter for a road registered car doing trackdays - you're still much better off than no rollbar - and they are permitted for use with road registered cars. The 50mm clearance only applies to nonregistered cars that are CAMS logbooked. And in those cars, a legal rollbar will usually require running with no roof, or with holes cut in it, or a lot of mucking around to find a seat that maximizes head clearance.

So for anyone who wants to get into trackdays, I'd recommend you get a BD or MX5 Plus rollbar for your NA or NB. Those with an NC already have some rollover protection in the stock roll hoops and strengthened A pillars. Stronger rollbars are available for NCs if you want extra peace of mind (still allowing softtop operation).

[greenMachine]

On the note of head clearance ... I am 6'2" and intend on tracking the car ...

It is not your height that is the issue, it is how long your legs are! Put another way, the critical dimension is how high above the seat is your head. If you have long legs/short torso, you are in a better position than someone who is short legged but with a long torso.

I have seen relative 'shorties' have clearance problems that you would not image from just how tall they are.

So don't go on your height, have someone measure the clearance between the top of your head and the top of your roof, and you will know precisely where you stand (sit ). Ideally do it with a helmet on.

Note Guran's advice re the different standards for road registered cars compared to unregistered racecars. There may also be differences between the different sanctioning bodies (ie CAMS, AASA, MRA), but CAMS seems to be the strictest from my limited observations.

[snshami]

You know something. Suddenly I am not as convinced about my position as I was. If I could fit a rollbar that is not in a position for me to bang my head against and looks half decent I probably would consider it. I had a look at some of the bars such as the Brown Davis and the metal pipes look like they would be dangerously close to the back of my head.

[hks_kansei]

true, pretty much any rollbar that's going to be any use will be close to your head.

however, that's why Victorian law requires them to be padded.

$10 will get you a one meter length of proper rollbar padding that has been tested etc to protect in a crash. (one meter was enough to do all the forward facing bars on my brown davis)

[Gdekwant]

Thanks for the information guys, I realise the 50mm isn't necessary for road registered cars or at all for the events I'll likely do however I feel getting that clearance is always a good thing, considering I have not yet purchased a seat or rollbar I was hoping to figure out which items would provide the best clearance in the event of a roll.

Thanks again.

[snshami]

true, pretty much any rollbar that's going to be any use will be close to your head.

however, that's why Victorian law requires them to be padded.

$10 will get you a one meter length of proper rollbar padding that has been tested etc to protect in a crash. (one meter was enough to do all the forward facing bars on my brown davis)

Next time we are both at the Garage Cafe, would you let me have a closer look at your roll bar?

[hks_kansei]

Certainly, I'll let you know when I'm down next.

[Shambler]

Wow.
Reading this thread has just made me really want a Roll-bar! I'm reasonably sensible when driving however accidents happen and I certainly don't want anything like what's been shown already to happen to me!
Will look into the BD or mx5plus I think!

[Mr Morlock]

It is interesting that folks think this is an easy choice. I posed the analogy about a boxer wearing gloves and hitting you in the head- or perhaps are there any takers for a baseball bat swung with intent- but wait guys it is wrapped in energy absorbent material so no probs. And ask Mazda even about the NC and the roll bar- I did and it was not even a talking point. A roll bar too close to your noggin is not a good thing.

[Dweezle]

Well energy absorbent material must work.



remember when Bart removes the foam

[hks_kansei]

the whole rollbar debate is about shifting the statistics.

let's just apply some arbitrary numbers.

Without rollbar:
likelyhood of rear end collission: 30%
likelyhood of rear end collission Injury: 10%

likelyhood of Rollover: 5%
likelyhood of Rollover Injury: 80% (nothing above your head basically means guaranteed death)


With rollbar:
likelyhood of rear end collission: 30%
likelyhood of rear end collission Injury: 30%

likelyhood of Rollover: 5%
likelyhood of Rollover Injury: 50% (much lower death risk)



remember of course thos are complete guesses, I have no idea about the actual likelyhood of any of those events.

but basically, I look at it from the view that without a rollbar, if it rolls, I WILL die unless there's some very unlikely event that spares me.

with a rollbar, I have greatly increased the risk of my being injured in a smaller accident, but if i do ever roll, I now have a higher likelihood of being severely injured and not dead.


if I have 9 rear enders and 1 rollover, I'd prefer be more injured 9 times, and then be injured the final time in a roll.
as opposed to walking away 9 times and then being dead in a rollover.


Injuries, even severe ones, heal to a degree. Death will not.



Morlock, this topic is one that we both have strong opinions on, and I do love a good debate.
the Melbourne MX5 guys meet in Carlton every Thursday night (details in the meet section of the forum)
I would genuinely like to have a sit down one night and have a good discussion (and of course show you some of the rollbars available in case you have not seen them before) about the rollbar debate.

[deviant]

It is interesting that folks think this is an easy choice. I posed the analogy about a boxer wearing gloves and hitting you in the head- or perhaps are there any takers for a baseball bat swung with intent- but wait guys it is wrapped in energy absorbent material so no probs. And ask Mazda even about the NC and the roll bar- I did and it was not even a talking point. A roll bar too close to your noggin is not a good thing.

But for some drivers the risk of coming in to contact with the roll bar is non-existent. For some there is a small risk. Like everything in life these risks can be controlled and minimised as much as possible.

I would rather live with the small risk of coming in to contact with the roll bar and dealing with the consequences of that over being crushed by a 4X4 running in to and over the back of my car or at best being paralysed from the chest down after a roll over.

On the NC there is no way your head could come in to contact with the roll hoops. The seats completely separate the driver from them.