Roll Cage.

[ptc]

I understand its ultimately up to a Track Tech - "Authority having jurisdiction" which doesnt always take into consideration logic and the 'intent of a rule'.... I live and work in the spec, code, rule and legal world so I know how to dissect and interpret things.

So Vin, just for discussion purposes between logical minds lets break down the roll bar rule: Which is a "Minimum Standard" and can be added to all you want to make it better.

4:10 ROLL BAR
1. All roll bars must be within 6 inches of the rear, or side, of the driver’s head, extend in height at least 3 inches above the driver’s helmet with driver in normal driving position or be within 1 inch of the roof/headliner in the area above the driver's helmet, and be at least as wide as the driver's shoulders or within 1 inch of the driver's door.

2. Roll bar must be adequately supported or crossbraced to prevent forward or lateral collapse. Rear braces must be of the same diameter and wall thickness as the roll bar and intersect with the roll bar at a point not more than 5 inches from the top of the roll bar. Crossbar and rear braces must be welded to main hoop.

3. Sidebar must be included on driver’s side and must pass the driver at a point midway between the shoulder and elbow. Swing-out sidebar permitted.

4. All roll bars must have in their construction a cross bar for seat bracing and as the shoulder harness attachment point; cross bar must be installed no more than 4 inches below, and not above, the driver’s shoulders or to side bar.

5. All vehicles with OEM frame must have roll bar welded or bolted to frame; installation of frame connectors on unibody cars does not constitute a frame; therefore it is not necessary to have the roll bar attached to the frame.

6. Unibody cars with stock floor and firewall (wheeltubs permitted) may attach roll bar with 6-inch x 6-inch x.125-inch steel plates on top and bottom of floor bolted together with at least four 3/8-inch bolts and nuts, or weld main hoop to rocker sill area with .125-inch reinforcing plates, with plates welded completely.


Section 1 dictates the specs for where the bar must be in relation to the driver.

Section 2 now tells us about the ROLL BAR and its supports, but all this rule stipulates is that a ROLL BAR must be "adequately supported to prevent forward or lateral collapse", that is the ENTIRE basis for this rule. However, nowhere in the entire rule does it state REAR BARS ARE REQUIRED. So it could be interpreted that a forward brace and a lateral brace could support the same ROLL BAR from collapsing - yes?

What the rule does say and is intended is "IF" Rear Bars are used, they must meet certain criteria to support the ROLL BAR. Most people would rather go backwards instead of forward in cars because thats where the space is to do it. The rule was not specific to TRUCKS.... But the INTENT is the SAME~!

In section 3 there IS a requirement for a sidebar at the driver side.

Section 4 covers cross bracing for seats and belts that MUST be installed

Section 5 covers welding and bolting to OEM frame... its very vague and its intention is only that the connection must be SECURE.

Section 6 covers Unibody cars MAY do this and that blah blah blah.... (are not safe at all - IMHO )

So If I presented you with a 4 point mounted Rollbar (2 in front to front cab mounts, 2 in back to rear cab mounts) and 2 more lateral bars going from rear hoop inward to a frame cross member (total of 6 points) all bolted to mirror plating beneath the cab - would you as a tech inspector accept my installation as meeting the intent of the RULE 4.10?

Thanks for reading....