Re: alfa-digest V7 #690 - Roll Bars

[AlfaNeely@domain.elided]

	Caution!  The specifications Chris Poore provides in Alfa Digest V7 # 
690 are for roll CAGES, not for roll BARS.  Otherwise, they appear to have 
been transcribed rather accurately.  For example, my 84 ITB Alfa Spider is 
required to weigh 2400 pounds.  Less 180 for the driver and it weighs 2220 
pounds, or just over the third weight bread for IT/ShowRoom stock.  I am 
using 1.75 x 0.095 DOM 1020 mild steel for my roll cage.  I could have used 
1.50 x 0.120 tubing.
	The difference is, obviously, that a roll cage has front legs so that 
the roll bar does not take all the impact of a roll over.  Also the lighter 
tubing allowed for GT / Production cars vs IT/ShowRoom is that more tubes are 
required.  IT/Showroom cages were originally bolt in only with six attachment 
points and no cutting of the dashboard for installation.  These can now be 
welded in and can penetrate the dash and be attached at eight points, but the 
cage is still basically an add on rather than a part of the overall car 
design.  Thus, heaver tubing is required.
Ciao,
Russ Neely
Oklahoma Region SCCA Scrutineer (Screwed in the Ear) a/k/a tech inspection 
worker
	

In a message dated 5/5/99 4:14:34 PM Central Daylight Time, 
owner-alfa-digest@domain.elided writes:

<< 
 Date: Wed, 05 May 1999 17:00:22 -0400
 From: Chris Poore <caspo@domain.elided>
 Subject: Re: SCCA roll bar rules/Synthetic Oil
 
 Let me first start off by saying that my first car was a VW Fox which
 became a DSP autocrosser. When sold at 210,000 miles could still pass
 the new car specs for engine compression. I had used Mobile 15w50 from
 5000miles on.
 
 The SCCA general compitition rules are as follows:
 
 6. Material:
 
 A. Seamless, or DOM (Drawn Over Mandrel) mild steel tubing
 (SAE 1010,1020,1025) or equivalent, or alloy steel tubing
 (SAE, 4130) shall be used for all roll cage structures. Proof
 of use of alloy steel is the responsibility of the entrant.
 
 B. Minimum tubing sizes (all Formula, Sports Racing, GT, and
 Production Category automobiles, and all automobiles
 registered prior to June 1, 1994) main and front hoop (All
 dimensions in inches):
  Vehicle Weight Material
  Without Driver Mild Steel Alloy Steel
  Up to 1500 lbs. 1.375 x .095 1.375 x .080
  1500-2500 lbs. 1.50x .095 1.375 x .095
  Over 2500 lbs. 1.50x .120 1.50 x .095
   or 1.75 x .095
 
 C. Minimum tubing sizes for (all Showroom Stock, Touring
 and Improved Touring Category automobiles registered
 after June 1,1994) main and front hoop, downtubes, rear
 supports, diagonal:
 
 Up to 1500 lbs 1.375 x .095 DOM I Seamless I Alloy
 1501-2200 lbs 1.500 x .095 DOM I Seamless I Alloy
 or 1.500 x .120 ERW
 2201-3000 lbs 1500 x .120 DOM I Seamless/Alloy
 or 1.750 x .120 ERW
   1.750 x .095 DOM I Seamless I Alloy
 (American Sedans may constmct to these
 specifications regardless of weight.)
 3001-4000 lbs 1.750 x .120 DOM I Seamless I Alloy - No
 ERW
 
 Also:
 
 GCR141
 6. Bracing:
 
 The main roll hoop shall have two braces extending to the rear
 attaching to the frame or chassis. Braces shall be attached as
 near as possible to the top of the main hoop not more than six
 (6) inches below the top and at an included angle of at least
 thirty (30) degrees. On cars where the rear windowibulkhead
 prohibits the installation of rear braces (e.g., Honda del So~), the
 main hoop shall be attached to the body by plates welded to the
 cage and bolted to the stock shoulder harness mounting points.
 This installation design must also incorporate a diagonal bar
 connecting the top of the main hoop to the lower front passenger
 side mounting point ("Petty Ba:").
 
 7. Side Protection:
 
 A side tube connecting the front and rear hoops across the
 driver's door opening is mandatory and across the passenger's
 door opening is allowed (recommended). The telescope section
 should be at least four (4) inches in length. Minimum bolt
 diameter 3/8 inches. The driver's window safety net may be
 mounted to this side tube and the top cage tube. Driver's door
 side tubes may extend into the door. NASCAR-style side
 protection is penniffed. The driver's door window glass, window
 operating mechanism, inner door trim panel, armrest, map
 pockets, and inside door IatcMock operating mechanism may
 be removed and the inner door structural panel may be modified,
 but not removed to facilitate this type of side protection. The
 stock side impact beam and the outside door latch/lock
 operating mechanism shall not be removed or modified.
 
 8. Mounting Plates:
 
 A. Each mounting plate shall be at least .080 thick if welded
 and 3/16" thick (with appropriate backing plates) if bolted.
 There shall be a minimum of three (3) bolts per mounting
 plate if bolted.
 
 B. Each mounting plate shall not be greater than 100 square
 inches and shall be no greater than twelve (12) inches or
 less than two (2) inches on a side.
 
 C. Whenever possible, mounting plates shall extend onto a
 vertical section of the structure (such as a rocker box).
 
 Also the GCR states that Hardware should be Grade 5 or better and 5/16"
 minimum diameter
 
 Hope that helps. Also this is my first entry to the digest, sorry if I
 get the format al wrong.
 
 Chris in SC
 
 79 Alfetta
 87 Milano Gold
 95 VW Golf
 96 Audi A4
  >>

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End of alfa-digest V7 #694
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