Technical notes

Technical notes – Very Important

Non-factory restraining devices

Rennsport recommends that any non-factory restraining devices / harnesses / belts should be regularly inspected for signs of damage or wear. In addition, they should be rewebbed as often as recommended by the manufacturer, or 10 years past the SFI manufacturing date, which ever occurs first.

Boxster and Cabriolet Owners

No Mandatory Broomstick Test for Boxsters and 996 Cabriolets at DE.

At the July meeting of the Rennsport Executive the directors voted to abolish the “broom stick” test for Boxsters and 996 Cabriolets driven without hardtops at Driver’s Education events. While it seems obvious that roll bar extensions should offer additional protection for tall occupants, there is no evidence to prove it one way or the other.

Rennsport strongly recommends the use of equipment designed to improve safety but the responsibility is ultimately that of the driver.

Zone 1 rule. (Could be enforced at other regions/tracks).

All open cars must have roll bars which conform to the following:

  • With the occupant(s) firmly and correctly belted into the vehicle, the occupant(s) helmet must be below a straight line drawn between the top of the windshield and the top of the roll bar (Broomstick Test). It is further recommended that roll bar be padded in any area that may come in contact with the occupant(s) helmet.
  • Take notice that the 996 Cabriolet’s roll hoops have a full extension
    of 5.25″. The same “Broom Stick” rules apply.

944/968 Front A-arms Check

Vehicles affected: 944 Stage II Cars (1985 & 1/2 or later, all 968’s, or earlier 944’s that have retrofitted cast aluminum lower front suspension). The problem is seen on 944’s that have been lowered and driven aggressively.

If a 944/968 has been lowered below factory specifications, it causes undue forces to be applied to the ball joint and the lower suspension member, increasing the possibility of failure of either component when driven aggressively. Installation of shorter or aftermarket springs with lower profiles also can contribute to the problem by changing the suspension geometry. Multiple failures of this type have been reported across Zone 1 in the past year.

In the interest of maximizing the safety of all entrants at our events, Rennsport will comply with the Zone 1 regulation and request that all subject cars that were lowered, be set to stock factory ride height. Ball joints and control arms should be checked and replaced if necessary.

Technical inspection for the Rennsport event will include a check for conformation to stock ride height for all 944/968’s equipped with the cast lower suspension arms. Stock height is defined as a minimum measurement of 13.0 inches from the center of the front wheel to the lower edge of the fender directly above the wheel centerline. Vehicles not meeting this specification will not be permitted to participate in the Rennsport Driver Education Event.

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