Roll Bar Supports

[_gonbau]

Here the earliest paper about the Matter roll cage I found, issued 18. March 1971, provided by DMSB (Deutscher Motor Sport Bund).
BR
Claudius

Attachment 608141
Attachment 608142
Attachment 608143
Attachment 608144

um... I consider this documentation to be of great beauty. I had not found anything similar even on Matter's own page which has some bars and information but nothing compared to this! Thank you very much for posting this! But I have to understand that before this bar there is the one that the other user mentioned (glavelel) but... At that time, was there approval for the bars?

[70SATMan]

Have you taken measurements of the hole locations as well as the distance between the holes and compared that to the factory roll bar base?

If the owner sourced the bar from Porsche, it would seem equally odd to me that either the factory mounting plates would not have been bought at the same time as the roll bar or that if bought, the decision was made to not install them. Given that a lack of funds or a lack of Porsche knowledge was not an issue.

[68S_SK2]

Well, I believe that a custom made plate was welded in, like in the picture of the yellow car, then drilled and a thread cut through the plate and frame. Later the welded plate was removed.



I think there were some more drill holes (green markings) but I can be wrong - or more likely, they stopped before drilling through the frame.



Here the dimensions of the SWB crow feet plate, the plates for the LWB cars were a little smaller as far as I know, but the dimensions should be the same.




Claudius

PS:
If you are interested in the DMSB paper, you can order it directly at: info@dmsb.de

[70SATMan]

That’s why I thought that the bar was likely not factory because the existing holes don’t appear to match the placement of a factory plate/factory bar.

[_gonbau]

Have you taken measurements of the hole locations as well as the distance between the holes and compared that to the factory roll bar base?

If the owner sourced the bar from Porsche, it would seem equally odd to me that either the factory mounting plates would not have been bought at the same time as the roll bar or that if bought, the decision was made to not install them. Given that a lack of funds or a lack of Porsche knowledge was not an issue.

I have measured the distance between them, 5 centimeters! Therefore, as you say, it's strange that the measurements match but the 'plate' is missing.

[_gonbau]

Well, I believe that a custom made plate was welded in, like in the picture of the yellow car, then drilled and a thread cut through the plate and frame. Later the welded plate was removed.



I think there were some more drill holes (green markings) but I can be wrong - or more likely, they stopped before drilling through the frame.



Here the dimensions of the SWB crow feet plate, the plates for the LWB cars were a little smaller as far as I know, but the dimensions should be the same.




Claudius

PS:
If you are interested in the DMSB paper, you can order it directly at: info@dmsb.de

I have measured the distance between the "threaded holes," giving me 5 centimeters, which matches the measurement you provided on the "front" part of the piece. I've attempted to use the ruler to measure the distances you mentioned from those holes, but I haven't found anything relevant. The "possible" holes you're indicating seem interesting to me, but if I'm not mistaken, aren't those original welding points from the Porsche assembly? I believe I've seen them in other restorations, so if someone could clarify this for me, it would be helpful. Again, thank you for those measurements of the piece and taking the time to show them! They have been quite "clear" and informative!

[_gonbau]

Why would only two holes be drilled instead of four/three?... Regarding the screws that held the bar to the chassis, were some longer than others, or were only two screws used for anchoring to the 'plate/chassis'?
The car had a sunroof, so I would like to ask what differences there were in the roll bars when they were with or without a sunroof.

[68S_SK2]

Why would only two holes be drilled instead of four/three?... Regarding the screws that held the bar to the chassis, were some longer than others, or were only two screws used for anchoring to the 'plate/chassis'?

That is supposed to be a craftsmanship error...
But it indicates according the congruent measurements, that a Matter roll bar base was used as a drilling template.

Concerning the sunroof: If I remember correct, the clearance is sufficient for the old style Matter roll bar to fit underneath a sunroof car, which is different to the now available roll bars.

[68S_SK2]

Here pictures of suspected factory style weldings:






Claudius

[911MRP]

That's something that seems strange to me, but perhaps it could be, as you say. I'm not familiar with the local scene, but I raise my doubt that someone who invests that much money in a car and is the founder and president of the Porsche club... would turn to a third party (not Porsche) to replicate a Porsche product (knowing that the Porsche ring existed at that time, so they'd be "replicating" its measurements). It seems odd to consider, but maybe it was a common method among racers since each might have had their own mechanic... Or did private racers who owned vehicles often go to Porsche dealerships for inspections and adjustments?

Porsche was not the be-all end-all for roll bars and cages. Some vintage photos of racers from that era in 911 suggest maybe Porsche were not as quick as some others to cotton on to the benefits of both safety / adding rigidity?


There were pioneering specialists in the field. Matter are well known as supplier of cages to Porsche (however not sure when Matter first made roll bars and roll cages?)

Other companies were available both to factory teams and to individual racers. One notable example in this field being ALEYBARS Limited. They under leadership of John Aley were a pioneering specialist in the field and were a popular fitment; active long before the devices became mandatory — a British company they were earliest to spot the need for such things and fill the demand:

This is a bit of historical context on the parent company Safety Devices website:
http://www.safetydevices.com/about-us/history/

An ALEYBARS brochure from the 70s is in the history link. The brochure says it started 1964 so had idea even before 911 drivers were creating demand —see claim in the leaflet of being earliesff if maker un Europe (and acknowledgements* by credible organisation who would know firsthand that Aley was the earliest maker of roll bars and roll cages).

Leaflet shows some details of the variants that time — including the aluminium version that was once deemed acceptable! This brochure in link is for historical interest and sone things clearly outmoded by current standards. Having worked as an advisor to the global leadership I know the FiA are constantly updating the rules and regulations regarding safety equipment:

Motor Racing magazine publications often featured adverts from ALEYBARS. This one featuring a Mini is evidently before UK decimalisation suggesting sixties?

An advert from spring of 1972:

This is a British 73 Carrera RS on a rally. I know it was fitted with an ALEYBARS manufactured cage. I suppose by then an off the shelf item for 911 application from this specialised cimpany given how prevalent 911 was in motorsport at that time.


I’d be surprised if ALEYBARS who had been going since 1964, hadn’t made rollbars/cages for 911 before in 1971 FiA mandated cages they were were becoming adopted in motorsport from latter half of sixtes. However compared to other marques/models used in motorsport Porsche 911 probably sold in low quantities.

ALEYBARS Ltd were used by a number of factory teams eg BMC competitions Dept as well as smaller teams and no doubt privateers used them in the typical seen racing back then.

Papers on file show my 73 RS was once fitted with a bolt-in ALEYBARS cage when it was owned by a racing driver who went on to win class at Le Mans. Being British company ALEYBARS of the day were certified by the Royal Automobile Club the FiA ASN in UK. Five decades ago the paperwork was provided in an envelope like this:


The certification was proof to scrutineers it was homologated by the RAC was recommended to be kept safe in case needed to be produced in continental European events:


The ONS certificate infomation posted by Claudius is interesting:
“Here the earliest paper about the Matter roll cage I found, issued 18. March 1971, provided by DMSB (Deutscher Motor Sport Bund).
BR Claudius”

Is the precise 18 March 71 date evidence of when Matter first made a certified roll cage product for 911? With roll bars/cages becoming mandatory racing equipment around then and Porsche 911 being popular in motorsport I can see why Matter would jump
in to developing and certifying them via German body ONS at that particular point. However the presence of Carrera model on that certificate with 1971 date is intriguing because the date on the certificate predates the existence of 73 Carrera RS — March 71 probably even predates the Carrera RS project being sanctioned by Porsche management or the model being named Carrera so hue dies that chronology fit? While there is no doubt a valid reason — maybe the certificates colourful bottom edge suggests recent print — the anachronism in content certainly caught my eye.

Perhaps Matter were supplying earlier than 71 and this paperwork was just related to certification for new mandate but if Matter only supplying from around that date where were Porsche getting roll-bars/cages before? The work team were using Britax ( British) harness from UK in sixties so did source racing safety kit outside German makers.

Back to the mounting. Interesting comment about completions regulations of 70s requiring bolt mounting this article from the well regarded Motor Sport ( see last full paragraph left column)

Also interesting to read author’s view on why aluminium roll over protection wasn’t successful.

Steve

*PS. For folks interested in history of innovation in motorsport this link has an obituary for John Aley who died several years ago.
http://www.brdc.co.uk/Notice-of-Deat...ey-1930---2021
As context, the BRDC is a club of racing drivers who must meet criteria of success to be invited to join and whom collectively own the Silverstone Racing Circuit. Members include past president Sir Jackie Stewart and the late Prof Sid Watkins who are both recognised internationally for making the sport safer so this acknowledgement by BRDC for John Aley’s contributions to safety (which no doubt saved lives of many motorsport participants) carries weight:
“John was something of a motor sport polymath. Racing driver, car club founder, race reporter, circuit manager, team manager, championship co-ordinator and car club chairman and president, he will be best remembered by a generation of racing and rally drivers for being the first person to manufacture roll bars for competition cars. Today it seems inconceivable that the use of roll over bars, let alone full roll cages, was not universal until 1971 when the FIA made them mandatory. Personal experience of being ejected from a rolling sports car during a test session at Snetterton had set John thinking along roll bar lines some seven years earlier in 1964 when he and Brian Wilkinson, who went on to found Safety Devices, produced the first Aley Bars.”