Roll Bars

[Jeff Alton]

Safety Devices and Autopower build decent bars. Would not consider them excellent or spectacular. The next step up would be a DAS bar. Ultimate would be a custom one that fit very tight and offered better all around support in the base plate area, but then it likely would not be true bolt in.

Cheers

[911tracker85]

Larmo63

now THAT is a cage....

I did a full bolt in cage on my 85 targa as it morphed into a DE / street car. it was very noticeable how much stiffer the chassis felt with the entire cage bolted in.

my current DE/street car is a 944 turbo. I got a custom made bolt-in similar to what you show from DAS from a local guy who makes roll bars and full cages. bolts to the seat belt points.

[AG81]

Thanks guys. Lot's of helpful information. I think I have decided on the Heigo Motorsports unit from Europe. I like the bolt in aspect of it. It's aluminum so the weight will be less than steel. It also uses adjustable mechanical connections so that should visually look cool. I plan to cover the tubing with similar materials I used on my interior leaving the mechanical connections exposed with a cerakote finish. Down side is it's a 12-16 week wait.




Red star horizontal bar won't be utilized as this is actually a 993 install. Blue star will be.

[Jeff Higgins]

Originally Posted by AG81

I've always been pretty leery of the bolt-in bars that utilize the rear seat seatback pivot bolt locations as anchor points for the braces. I much prefer a good, wide, thick steel pad under the bar. Here is how Autopower does it, putting that foot up on the inner fender. The outside of the inner fender has a similar plate, to which I welded the anchor nuts:



Here is a shot of the outboard bend that I tried to describe earlier:

[Trackrash]

Originally Posted by AG81

Thanks guys. Lot's of helpful information. I think I have decided on the Heigo Motorsports unit from Europe. I like the bolt in aspect of it. It's aluminum so the weight will be less than steel. It also uses adjustable mechanical connections so that should visually look cool. I plan to cover the tubing with similar materials I used on my interior leaving the mechanical connections exposed with a cerakote finish. Down side is it's a 12-16 week wait.




Red star horizontal bar won't be utilized as this is actually a 993 install. Blue star will be.

Aluminum roll bar? Interesting....

[911tracker85]

trying to find this. found the Heigo Motorsports web site but having trouble finding this rollbar.

how much?

as I am trying to get my 930 weight as low as possible an aluminum rollbar / cage would help. my safety devices steel unit is quite heavy.

[AG81]

^

By the time it gets here..... I am expecting about $2,100. No confirmation on freight but I'm thinking about $300 included in my price...... Wait time is 16 weeks due to race season in Europe, I'm told.

I plan to cover it in leather...... so this project is going to take a while.

https://www.fvd.net/us-en/HEI911001006A/roll-bar-911-930-aluminum-coupe-sunroof-bolt-in-x-diagonal-and-tunnel-support.html

[Locker537]

Is aluminum safe?

[Trackrash]

Originally Posted by Locker537

Is aluminum safe?

Let's see. 1.5" x 0.098" wall aluminum tubing? Diagonal braces that aren't tubular.

What do you think?

Minimum for NASA, PCA, and SCCA are 1 3/4" DOM steel in .125" thickness.

[AG81]

Originally Posted by Locker537

Is aluminum safe?

It takes about 3x the wall thickness of aluminum to equal steel in the same diameter tubing.........

[Trackrash]

Originally Posted by AG81

It takes about 3x the wall thickness of aluminum to equal steel in the same diameter tubing.........

I was surprised that the aluminum bar shown is thinner than my steel bar. I would have thought it would be much thicker than the 0.098.

[panzerfaust]

AG91. I would love to find a alloy 934 or matters 954 half Cage. I suppose the aluminum heigo would be the next closed vintage looking thing out there. Buddy of mine has the steel version, he was able to shoehorn the non sunroof steel heigo in to a sunroof 930. It’s fits nice and tight. I’m impressed with the quality.

[Dpmulvan]

I don't get the aluminum roll CAge? I guess it's just for looks not legal for the track.

[Locker537]

Originally Posted by Trackrash

Let's see. 1.5" x 0.098" wall aluminum tubing? Diagonal braces that aren't tubular.

What do you think?

Minimum for NASA, PCA, and SCCA are 1 3/4" DOM steel in .125" thickness.

I know what I think, but I wanted some factual or at least more experienced information.

[Flojo]

Originally Posted by coomo

Heigo appear to be the industry standard in Europe.I just managed to snare an Aluminium one at a good price.Its beautiful.

Heigo, Matter, Wiechers and some more… keyword is clubsport for the bolt-on ones.

[Flojo]

Originally Posted by Jack Stands

I’m unsure of the need for a rollbar in a street application unless it’s a cabriolet. I think they’re meant to be used with helmets.

these old 911 hold **** when rolling over, neither a coupe nor a targa.

[Flojo]

Originally Posted by Trackrash

Aluminum roll bar? Interesting....

weak like pvc plumbing tube

[Dpmulvan]

Thought some of you guys would like to see this

APPENDIX C - SOLO® ROLL BAR STANDARDS A. BASIC DESIGN CONSIDERATIONS
1. The basic purpose of the roll bar is to protect the driver in case the vehicle
rolls over. This purpose should not be forgotten.
2. The top of the roll bar shall not be below the top of the driver’s helmet when the driver is in normal driving position, and shall not be more than 6 inches behind the driver. Exception: For Modified Category Specials (Sec- tion 18.4), the bar must extend at least 2.0” (50.8 mm) above the driv- er’s helmet in the normal seated position and a head restraint keeping the driver’s head from going under or behind the roll bar is required. It is strongly suggested that all roll bars extend at least 3.0” (76.2 mm) above the driver’s helmet. In case of two-driver cars, both drivers must be with- in the roll bar height requirement, however only one (1) driver must be within 6.0” (152.4 mm) of the roll bar. In a closed car or an open car with a removable OE hardtop which is equipped with a roll bar/cage, it must be as close as possible to the interior top of the car.
3. The roll bar must be designed to withstand compression forces resulting from the weight of the car coming down on the roll structure, and to take fore-and-aft loads resulting from the car skidding along the ground on the roll structure.
4. The two (2) vertical members forming the sides of the hoop shall not be less than 15.0” (381 mm) apart (inside dimension). It is desirable that the roll bar extend the full width of the cockpit to provide maximum bearing area in all soil conditions during rollovers. The roll bar vertical members on formula cars and other single seat cars with a center driver position must be not less than fifteen inches apart, inside dimension, at their at- tachment points to the uppermost main chassis member.
5. An inspection hole of at least 3/16" (0.1875”, 4.75 mm) diameter must be drilled in a non-critical area of a roll bar member to facilitate verification of wall thickness. This should be at least 3.0” (76.2 mm) from any weld or bend.
6. It is recommended that steel gusset plates be used at all welds. Gussets should be at least 2.0” (50.8 mm) long on each leg and 3/16" (0.1875”, 4.75 mm) thick.
7. It is recommended that roll bars be coated only with a light coat of paint. If, however, a roll bar should be chrome-plated, it is recommended that the structure be normalized.
8. Post or tripod types of roll bars are not acceptable.
B. MATERIAL
After 09/22/1985, aluminum is not an acceptable alternate material. Cars using aluminum roll bars or roll cages must file proof with SCCA® Solo® De- partment that the structure was approved prior to 09/22/1985 as provided in this Section.
2017 SCCA® National Solo® Rules— 215
draft b
Roll Bars - Appendix C
1. The roll bar hoop and all braces must be of seamless ERW or DOM mild
steel tubing (SAE 1010, 1020, 1025) or equivalent, or alloy steel tubing (SAE 4130). It is strongly recommended that roll bars not be constructed of ERW due to quality and strength concerns.
2. The size of tubing to be used shall be determined on the basis of the weight and speed potential of the car. The following minimum sizes are required and are based upon the weight of the car without the driver.
Vehicle Weight (lbs.)
1501 - 2500
1000 - 1500
Under 1000
Tubing Size (min.)
outside diameter x wall thickness (in.)
1.500 x 0.095 1.625 x 0.080
1.250 x 0.090 1.375 x 0.080
1.000 x 0.060
Over 2500
1.500 x 0.120 1.750 x 0.095 2.000 x 0.080
Dimensions are nominal. 0.005” (0.127 mm) variation in wall thickness is
allowed.
3. Each mounting plate shall be at least 0.080” (2.03 mm) thick if welded and
3/16" (0.1875”, 4.75 mm) thick if bolted. A minimum of three (3) bolts per plate is required for bolted mounting plates.
4. All bolts and nuts shall be SAE Grade 5 or better and 5/16" (0.3125”, 8.0 mm) minimum diameter.
C. FABRICATION
1. One continuous length of tubing must be used for the hoop member with smooth continuous bends and no evidence of crimping or wall failure.
2. All welding must be of the highest possible quality with full penetration and will be subjected to very critical inspection. Arc welding, particularly heliarc, should be used wherever possible.
D. BRACING
1. It is recommended that braces be of the same size tubing as used for the roll bar itself.
2. All roll bars must be braced in a manner to prevent movement in a fore- and-aft direction with the brace attached within the top one-third of the roll hoop, and at an angle of at least thirty degrees (30°) from vertical. It is strongly recommended that two such braces be used, parallel to the sides of the car, and placed at the outer extremities of the roll bar hoop. Such braces should extend to the rear whenever possible.
3. It is suggested that roll bars include a transverse brace from the bottom of the hoop on one side to the top of the hoop on the other side.
216 — 2017 SCCA® National Solo® Rules
draft b

E. MOUNTING PLATES
1. Roll bars and braces must be attached to the frame of the car wherever possible. Mounting plates may be used for this purpose where desired.
2. In the case of cars with unitized or frameless construction, mounting plates may be used to secure the roll bar structure to the floor of the car. The important consideration is that the load be distributed over as large an area as possible. A backup plate of equal size and thickness must be used on the opposite side of the panel with the plates through-bolted to- gether.
F. REMOVABLE ROLL BARS
Removable roll bars and braces must be very carefully designed and con- structed to be at least as strong as a permanent installation. If one tube fits inside another tube to facilitate removal, the removable portion must bottom on the permanent mounting, and at least two bolts must be used to secure each such joint. The telescope section must be at least eight inches in length.
G. INSTALLATION ON CARS OF SPACE FRAME AND FRAME- LESS DESIGN
It is important that roll bar structures be attached to cars in such a way as to spread the loads over a wide area. It is not sufficient to simply attach the roll bar to a single tube or junction of tubes. The roll bar must be designed in such a way as to be an extension of the frame itself, not simply an attachment to the frame. Considerable care must be used to add as necessary to the frame structure itself in such a way as to properly distribute the loads. It is not true that a roll bar can only be as strong as any single tube in the frame.
H. ROLL CAGES
It is recommended but not mandatory that all cars utilize a roll cage as de- fined in the current Club Racing GCR Section 9.4, Roll Cages For GT And Pro- duction Based Cars, or Section 9.4.5, Roll Cages For Formula Cars and Sports Racing Cars.
I. ROLL BAR PADDING
Braces and portions of the main hoop subject to contact by the driver’s or passenger’s helmet, as seated normally and restrained by seat belt and har- ness, must be padded with a non-resilient material such as Ethafoam® or Ensolite® or other similar material with a minimum thickness of 1/2" (0.50", 12.7 mm).
Appendix C - Roll Bars
2017 SCCA® National Solo® Rules— 217

[onevoice]

Originally Posted by AG81

This type of attachment is not really safe in my opinion(and all sanctioning bodies agree).

A rollbar has only one purpose, ie to protect the driver. If you have witnessed many accidents, you know an attachment cantilevered off one bolt is not a good idea.

Maybe better than nothing, but not a roll bar. Seat belt attaching points are reasonably strong - FOR YOUR BODY, but they are not proper structure for supporting the forces a roll bar should protect you from.

[Geronimo]

If you have a roll bar on your street car haven't you already thrown safety out the window, unless you wear a helmet all the time or have a very well padded bar?