October 17, 2018
Comments noting ambiguities in this announcement, typographical or other errors in the specifications, and problems with changes which may have been overlooked may be addressed to the Rules Committee via e-mail (email@example.com) by using the contact form on this page. Submissions must be made by November 3, 2018.
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Car Number Requirements
The specification for the front car number is changed for 2019. The front number must be white, a minimum of four inches tall, and with one inch plain (no Gothic or Italics) stroke, installed horizontally (not tilted), and be located on the upper left side of the windshield (from the perspective of a person in front of the car – the upper right side from the perspective of the driver). If it is mounted on a banner, the background must have at least as much contrast as windshield glass.
GT and GTP cars without a windshield must have the front numbers a minimum of eight inches high, with a 1.5″ to 2″ plain stroke on the hood, centered, horizontal, and against a highly contrasting background.
It turns out that a number like this is highly visible, and its relatively small size and placement does not affect driver vision. Fancy script numbers in random places on sloping hoods against backgrounds with interesting graphics and tilted at artistic angles are nearly invisible and being able easily to spot cars returning from the track at 35 mph through the hot pits from ground level is an important part of Club Race operations. Existing numbers on the hood may be retained as long as they match the number assigned for the event on the windshield.
Car Weight on Car
All cars must display their minimum class weight on the upper part of the driver’s door shell in at least 14 point type with black numerals on a white background.
This weight should, of course, match that listed on the back of the cover of the log book, and comply with the weight from the weight chart or GT weight calculation, and be current for the configuration of the car at the event.
Safety – All Cars #9 (Firewalls)
Caymans may duct air from the quarter windows (where ducting from that window is allowed) or from the passenger compartment in tubes to the far rear corners of the rear trunk to cool supplementary fluid radiators installed below. Fans may be used to force air through these allowed openings for this purpose also.
Because openings are not a firewall integrity issue in the rear trunk of a Boxster, it is not applicable to that model.
Safety – Allowances
1) Every ABS whose PWIS programming includes an option for a PCCB flash may use that flash.
This may be done inexpensively at any Porsche dealership, as both programs are already installed on models with programmable ABS.
2) 924s, 944s, and 968, in every class, may add a bolted or welded flat plate to the front firewall where the clutch master cylinder attaches in order to reinforce the area where cracks may develop due to the master cylinder mounting. This modification may serve no other purpose.
3) The 7.B brake booster and master cylinder pressure change allowances are modified to include any Porsche parts which directly bolt in without modification and change nothing related to their performance other than to the allowed ratio or bore.
Stock – Serpentine Belts on Air Cooled 911s are a Prepared Modification
An interim rule (add 25 lbs) was adopted as an accommodation during 2018 for drivers in E Stock who had added an aftermarket serpentine belt system despite the fact that this is a Prepared modification. After considering this as part of the regular rule change procedure, it has been decided to drop the interim allowance for 2019. Those who made this modification have adequate time to put the stock pulley and belt system back in. Underdrive pulleys (other than for Boxster/Cayman power steering) have always been a Prepared modification, and no available serpentine system is not an underdrive. The instances of belts coming off on track but not related to misalignment of the pulleys, defects in one of the pulley parts, belts of improper dimensions, belt tension too loose, or faulty shifting are simply too few to justify complicating the class weight system.
1) Caymans and Boxsters and water cooled 911s may use any intake throttle body and plenum.
2) All E-gas models may use an aftermarket downshift blipper as a Prepared modification.
This was proposed for all classes, but while a blipper presents no significant performance advantage for a single lap, over the course of a race it is an advantage because even a single bobbled shift is a disadvantage, so it is a prepared modification in the Stock classes, and allowed otherwise only in the classes where the first two letters are GT.
The block may be sleeved to the original 2.5L spec.
PSS9s are an allowed alternate shock.
a) A 1/4th inch spacer for the rear wheels is allowed.
b) A bolt-on cross tie bar connecting the rear suspension sub-frame sides is allowed.
There will be no change in the allowed springs and rates. While the current rules produce a less than optimal suspension, everyone in SPB is faced with (discounting the use of the stock springs) just two choices. Adopting the proposal would raise that to four. It may be that some tracks favor one choice, and others a different one, and not everyone can DIY the alignment when done, or wants to spend the effort involved in sorting this out.
1) Cooling System additional allowances: The left and right stock radiators may be replaced with high efficiency front radiators provided they fit into the stock mounting points. Shrouding around the left and right radiators may be modified to allow for more efficient air flow to the radiators. A center radiator may be added and can be either a Tiptronic or GT3 type. The center radiator may be vented out either from the bottom, or through the top between the bumper and front deck lid equivalent to a 997 GT3. Radiator fans may be direct wired with a switch, and one of them may be removed.
2) The required stock headers may be externally wrapped.
a) Door windows, plastic or otherwise, are not allowed.
b) External door mounted mirrors are free.
c) The 2003-06 996 GT3s may run in GTB under the stock J class rules for this model, and with tires being free (DOT not required).
Note that this If it becomes clear that these cars cannot compete at stock weight, or are determined to have an advantage, a competition adjustment may be made when appropriate at any time during 2019. In addition, allowing these cars in GTB will be reviewed for 2020, since reversion to J will not involve significant expense.
At Road America it was found that several J class cars which would be eligible to run in GTB under this rule change had wings which were not the stock GT3 wing. Because none of the special allowances beyond stock, other than tires, apply to GT3s in GTB, drivers must be careful to run the stock wing only.
These rules are unchanged for 2019, and the minimum class weight remains 3100 pounds for both allowed models.
GTP – GT:
The provisions related to pre-996 911 chassis are deleted. GTP is thus limited to factory approved prototype race cars, as well as a now very small number of cars grandfathered because they had a log book as a GT car before 1999. Cars covered by the deleted provisions will be classed in GT.
The Porsche Motorsport approved ABS is allowed in this class
The principal proposal to modify the championship points system for 2019 is adopted.
Three regular races per event will count for points (excludes the fun race, a reverse start race or the like, or a race where entry is specially limited, such as a night race requiring prior race experience on the track, the same as the current rule). In order to qualify for a year end podium, you must start at least eight points races. The best thirteen finishes will be used to determine where you finish. And bonus points will be awarded based on the number of cars which start the race which you finish ahead of.