dave-C2

I’m about to install a factory RS style roll cage in my 964. The car is still registered for the street in the US, but it is almost exclusively a track car.

Unless I’m mistaken, Porsche offered the 964RS and 993RS/CS in Europe and the UK as roadworthy cars with full cages, although these cars were primarily intended for track duty. Because of US DOT regulations there was no way Porsche could or would sell these cars in the US. A few may have slipped into Canada, however, so those owner’s comments would be welcome.

Over the last few years there have been some discussions on the Racing and DE forum regarding the potential hazard of roll cage bars when driving on the street. The largest concern focuses on an unprotected head hitting the cage during a road accident. This appears to be possible since all seat belts or harnesses will stretch during the high G loadings associated with an accident.

Does anyone know if Porsche was obliged to submit the RS cars for any certification testing to confirm road safety with the exposed roll cage?

If the cars were not tested, how were they certified for street use?

Lastly, does anyone have any information on whether the RS roll age bars have actually been a problem in street accidents? Gruesome details not required

Thanks in advance for any information.

joey bagadonuts

Dave,

I think I have pretty much zero information relative to your very specific questions ( ) but I wanted to ask if you planned to Club Race your car any time in the future? I'm asking because I was under the impression that the Factory cages produced by Matter were made of aluminum. Unless you are running a Cup Car, I'm not sure such an item would be legal in PCA racing. And I don't believe an aluminum cage is allowed in NASA, either.

As for driving around town with a cage, remember, you'll probably install thick, foam padding around the strucuture at locations where your body might come into contact with it. I'm not sure an impact against such an object is any more hazardous than bouncing off the side windshield, dash or A pillar. I think you'd need to run that question by an engineer from the NTSB to be sure. An unpadded cage, however, would be a different story.

964russ

If you crash it hurts! Cage or not!
Some one else on this forum knew sum more about cages and street use, basicaly not advised for road/street use, due to head injurys.
Allso europe/UK laws dont restrict cars with any form of rollcage! Dosent even come into UK MOT checks. But a car with a cage cant be more dangerous than without? Dont know about the US laws. And i dont think foam or any other type of padding will stop head injurys on a safety cage, thats why u where a helmet whilst on a track.

Geoffrey

The Cup car cages are steel, not aluminum. I don't know where that piece of misinformation comes from as I've heard it a number of times. The last time I saw an aluminum roll cage was in a 935.

cupcar86

Correct, this weird misperception keeps coming up, all cup car cages are steel, welded to to steel pickup points on the chassis which is simply not possible with aluminum which can generally only be attached to steel via adhesive/riveting as far as I know.

joey bagadonuts

I thought I saw an aluminum Matter cage offered in the Parts For Sale page of this website (it's no longer there, of course):
http://www.porsport.com/

Perhaps it was for a 935, the ad wasn't specific. But if you guys say the 964 versions are made of steel, then I'm sure that's the case.

As for the street safety concern, there's a current discussion on this topic in the Racing/DE forum. The focus shifts to rollcage safety on about page 4 and there's no real conclusion except that no factual data exists which confirms that a rollcage represents greater risk in a street-driven car. The bottom line is to educate yourself on the matter, make an informed decision and assume responsibility for your actions.
https://rennlist.com/forums/racing-and-drivers-education-forum/379079-5-pt-or-6-pt-harness-for-de.html

docwyte

I sure wouldn't want to hit my head on the main cross hoop of a cage without a helmet on, padding or not. Seems like a great way to get serious head trauma.

LA964RS

Don at Porsports had a steel matter cage (which I know where it is) and an aluminum Ruf cage (which I know where that is too)....

David P

Don't know if this helps, but Vic Roads down here in Australia has the following to say about roll cages in street cars:

http://www.vicroads.vic.gov.au/NR/rd...65/0/VSI28.pdf

Perhaps you local road authority has something similar?

Regards

David P

SimonExtreme

First thing to understand is that these cars are 15 years old and the regulations have changed since then. I know that in some countries in Europe, the Clubsports weren't sstreet legal and the cage was the reason. I do not believe that there was any testing or type approval.

As for driving a car with full cage on the road, the simple fact is that in an accident, you are far more likely to suffer a serious injury if you have a cage than if you don't. Obviously the number 1 problem is head making contact with the cage, which is pretty serious, but you are just as likely to bang other parts of your body, such as arms and legs, unless you are strapped in by a harness. Forget the padding you see on some cages. With the inertia that happens in some crashes, it doesn't help at all. Even if you are in a harness, your head is still at risk.

Wearing a harness on the road really isn't a good idea. For instance, try pulling out of a side road when you cannot lean forward to see what is coming and you cannot turn to look at blind spots before pulling out.

Having said all that, I know a reasonable number of people who drive to and from tracks in cars with full cages. However, I don't know anybody who uses a 964 with a full cage as a regular road car.

On the other hand............ 996 GT3's were supplied with full cages and I would imagine that these are type approved. I have never bothered to check this out too closely to see how they make the cage safe, but I assume that it must be to do with the routing of the cage plus I don't know if there is special trim as well.

38D

Do you have any data to back this up or are you just speculating?

I personally don't think hitting your head on a properly padded cage (the hard stuff, not the noddles) is any more or less dangerous (or likely) than hitting your head on A pillar -- but that is purely speculation on my part.

kleinbbc2

My buddy just rolled his 944t from a lady in a SUV coming across and hitting his door causing him to lose control and end uprolling and flipping the car in a FL ditch. He walked away car is total and from what I seen every piece of sheet metal is crushed around the cage. He tells me he thinks the caged saved his life.

YYC930

I'd rather risk banging my head on a properly padded cage crossbar than letting it snap backward aimlessly and probably breaking my neck.

Having said that, you are all missing a crucial point here......for decades the OEM Porsche seats have integral fixed headrests built into them.....Recaro race buckets are the same. So, if you hit something in front of you hard enough to send you flying back, your head is going to first hit your seat back, which will then flex and possibly hit the padded crossbar. Your head won't touch it in 99% of all accidents.

It's a no brainer IMHO.

Mark in Baltimore

I've driven my race car on the street quite a number of times and had no issues with the harness preventing me from seeing traffic properly. My car has convex mirrors everwhere, as it should, so blind spots are not an issue.

SimonExtreme

First off, in some countries convex mirrors don't comply with car construction standards! However, I suspect that the difference in experience might be due to different traffic conditions.

The biggest single issue with wearing harnesses on the road is when you come out of a side road into main one, either turning into it or going across. It would be fine if there were always no cars parked in the main road, but if there are you have to lean forward to see what is coming, The alternative is to stick your nose out until you can see. I can assure you that you could not drive in London or Sydney safely while wearing a harness. It also happens to be against the law in many countries.

I also suspect there is some confusion in what we are talking about because I don't understand the. A head rest does nothing to stop your head hitting anything in front of the seat so with a full roll cage, it does no good. Next, if you hit something ahead, you are thrown forward, not backwards. Even then, most caiidents aren't simply either head on or rear enders. Research shows that most accidents happen at some angle to the centre line and if you have ever watched a crash test dumby being thrown around, you will realise why you don't want anything as hard as a roll cage in your way.

The other thing you need to consider is that teh fitting of a full roll cage actually means that there is serious metal even closer to your head. The bar above the door is particularly dangerous.

Finally, I am sur ethere are stories about people having their life saved on the road because of having a roll cage. I also know of a friend who wouldn't be here today if he had been wearing a seat belt. However, I will keep wearing a seat belt and not just because it is law.