Rollcage for drifting: specs? [Archive]

k4rr

11-16-2007, 01:54 AM

Found my own answers!! yay

3.18 Rollbars/Cages:
This is a general overview. All SFI/SCCA specs apply contingent upon vehicle construction. Nothing herein should be construed to override existing SFI/SCCA specifications. All vehicles competing must have roll cages installed.
A) The purpose of the roll cage is to protect the driver from injury if the car is involved in a crash or a rollover accident. The roll cage should be built to withstand a crash, a rollover and an extended slide on the side of the car or on the roof of the car.
B) Roll cage material must be DOM. The following diameter and thickness must be used when constructing your cage. The material depends on the weight of the vehicle without the driver and liquids.
Up to 1500 lbs.
1.375” x 0.095” Seamless mild steel (DOM)
1501 - 2200 lbs.
1.500” x 0.095” Seamless mild steel (DOM)
2201 - 3000 lbs.
1.500” x 0.120” Seamless mild steel (DOM)
1.625” x 0.120” Seamless mild steel (DOM)
1.750” x 0.095” Seamless mild steel (DOM)
3001 - 4000 lbs.
1.750” x .120” Seamless mild steel (DOM)
Over 4000 lbs.
2.000” x 0.120” Seamless mild steel (DOM)
C) Main hoop 4 bends maximum, totaling 180 degrees ± 10 degrees.
D) Front hoops 4 bends maximum or Front down tubes 2 bends maximum.
E) Rear hoop supports must have no bends.
F) If any one of the above bend requirements are not met exactly then all components of the roll cage must be fabricated using the tubing size(s) listed for the next heavier category of vehicles.
G) An inspection hole between 3/16 inch diameter and 1/4 inch diameter may be drilled by NOPI Drift in a non-critical area of all tubes with a specified size to check the wall thickness.
H) All bends must be mandrel bent with no evidence of crimping or fatigue, no crush bends will be allowed.
I) The radius of the bends shall not be less than three times the diameter of the tubing used.
J) All Welding shall conform to the American Welding Society D1.1, 1994 edition,
Structural Welding Code, Chapter 10, Tubular Structures and Standards.
K) There should be no area of the cage where 2 steel components come together and are not welded.
L) Welds must be continuous all the way around the entire tube.
M) The welds will have no cracks.
N) The welds will have thorough fusion and penetration.
O) All craters shall be filled.
P) If any undercut is present it shall be no more than 0.01 inches deep.
Q) All welds must be tig or mig welded.
R) The cage shall be bolted and/or welded to the car.
S) It shall attach to the car with at least six mounting points.
T) The forward part of the cage shall be mounted to the floor of the
U) Vehicle and gussets are recommended for mounting the cage to the side rails of the car.
V) Two optional front bars may be installed and they can be mounted to the front down tubes of the cage and go forward through the firewall. These two front bars must mount to the rear of the shock tower.
X) Reinforcing bars are permitted within the structure of the cage.
Y) The cage can be attached to the structure of the vehicle with additional bars or plates.
Z) No part of the roll cage should come in contact with a driver’s helmet at any time. Bars that are close to the driver’s helmet must be padded with padding that is at least 0.5 inches thick. Ethafoam® or Ensolite®, or other similar material is recommended. Padding meeting SFI spec 44.1 is recommended
3.18.2: Main Roll Hoop Components:
A) The main hoop (behind the driver) should start from the floor of the car and be one continuous length of tubing.
B) The Main hoop shall extend the full width of the driver/passenger compartment.
C) The Main hoop shall be as near to the roof as possible.
D) It shall incorporate a diagonal lateral brace to prevent lateral distortion of the hoop.
E) The diagonal lateral brace will be made of one piece.
F) If an additional diagonal lateral brace is used it shall be 2 pieces as well.
G) It shall incorporate a horizontal brace that the harnesses can attach to and that provides a secure seat back support. This horizontal brace will be constructed of tubing equal to the roll bar and shall be installed horizontally from the main hoop upright to the diagonal brace. There shall be a horizontal bar installed on the driver’s side and on the passenger side if there is a passenger seat and a passenger harness. The tubes will not be higher than shoulder height of the driver and passenger.
3.18.3: Front Section of the cage:
A) There are three different options for building the front section of the cage, they are as follows; Side hoops, front hoop or halo.
B) If side hoops are used then they should follow the line of the front pillars from the floor board to the top of the windshield. They should run as close to the a pillar as possible, as close to the windshield as possible and then run along the top of the roof where it meets the door back to the main hoop. The two side hoops are connected together with a horizontal bar that runs between the two side hoops along the top of the windshield where it meets the roof of the car. The part of the side hoop that runs horizontal back to the main hoop should be as close to the side of the car as possible and as close to the roof as possible.
C) If a front hoop is used then it should come up from the floor board and run as close to the pillars as possible and then run horizontally along the top of the windshield where it meets the roof of the car. It should be constructed out of one piece of tubing. The front hoop is then attached to the rear hoop by two pieces of tubing that run along the roof back to the main hoop. These 2 horizontal pieces should be as close to the side of the car as possible and as close to the roof as possible.
D) If a top halo loop is used it must follow the roof line from the main hoop forward to the top of the windshield and then across the top of the front windshield staying as close to the roof as possible. The portion of the halo that runs forward from the main hoop must be as close the side and the roof of the car as possible.
E) The portion of the front or side hoops that extend from the floor board to the top of the windshield along the pillar may extend through the dash board. If the door panels contribute to the dash board when the doors are closed the bars may extend through them as well.
F) It is highly recommended to have one horizontal bar between the two front down tubes. It should be placed high enough to be behind the dash board.
3.18.4: Rear Bracing:
A) There shall be two braces extending to the rear of the vehicle from the main hoop. The braces will be attached as close to the top of the main hoop as possible and not more than six inches below the top and at least an included angle of 30 degrees. If the rear window or bulkhead prevents installation of the rear braces then the main hoop needs to be attached to the body by attachment plates. These plates shall be welded to the cage and attached to the vehicle by bolting them to the OE shoulder harness mounting points
3.18.5: Side Protection:
A) A single side tube on both the driver’s side and the passenger side door openings is mandatory. This side tube will connect the main hoop to the front down tubes and protect occupants of the vehicle from side impacts.
B) These side tubes may extend into the door.
C) The windows may be removed and replaced with lexan windows with steel frames.
D) If the vehicle is equipped with OE inner door bars then one single side tube is required.
E) If the vehicle is not equipped with an OE inner door bar then 2 sidebars or an X configuration is required.
F) NASCAR-style side protection is recommended.
G) If NASCAR style or similar side protection is used then the window operating mechanism, inside door trim panel and arm rest, and the inside door latch/lock operating mechanism may be removed.
H) If NASCAR style or similar side protection is used then the inner door structural panel may be modified, but not removed.
I) If there is a door bar OE in the door then try to leave it and use the NASCAR style or similar side protection.
J) The stock outside door latch/lock operating mechanism will remain stock and function in its OE manner.
K) If the sidebar or bars are removable or part of a bolt in cage then all rules for the bolt in cage are required to be met. The sleeves for the side bars can be reduced from the 8 inch length to a 4 inch length and the bolt holes should be drilled between 0.75 and 1.25 inches from the edge of the sleeve. Minimum bolt diameter is 3/8 inches.
L) Windows must be present and in the up position when racing.
3.18.6: Mounting Plates:
A) Mounting plates are used in areas where the end of the cage tubes butt up against the vehicles body.
B) Mounting plates need to be at least .080 thick if welded and
3/16” thick if bolted.
C) If the plates are bolted then there must be an additional 3/16” mounting plate on the other side of the vehicle structure to be used as a backing plate. If bolted, the plates also must be at least the thickness of the tube with the thickest wall that attaches to it. A minimum of 3 bolts will bolt the 2 plates together with the vehicle structure being in between the 2 plates. The minimum size of the bolts shall be 5/16 inch and grade 5 or better.
D) The area of the mounting plates should not be greater than 100 square inches and the lengths or widths shall be between 2 inches and 12 inches.
E) The mounting plate may be multi-angled but must not exceed these dimensions in a flat plane.
F) It is recommended that mounting plates should extend onto a vertical section of the structure when possible, such as a rocker box.
G) As many tubes as needed may attach to a single plate or to each other.
3.18.7: Additional considerations for bolt in roll cages:
A) Bolt in roll cages are expected to be fabricated to be as strong as a fully welded roll cage.
B) Joints shall consist of one tube fitting inside another tube to facilitate removal the outer sleeve must be of the same or greater thickness as the primary roll cage material.
C) The inside diameter of the sleeve material must be within .025 inches of the outer diameter of the primary tubing material.
D) The sleeve will be at least eight inches in length.
E) There will be a minimum of two bolts that will penetrate through the sleeve and the primary tubing to mount the two pieces together.
F) The bolts will be at least 3/8 inches in diameter and should be grade 5 or better.
G) The primary tubes will not have more than a 0.5 inch gap in between the ends that lie beneath the sleeve.
H) The holes will not be drilled any closer than 1 inch to the edge of the sleeve and not more than 2 inches from the edge of the sleeve.