"Boxster Spec-X" BSX Class Rules for 2010
(Final Draft)
Class PurposeThe purpose of this Spec Class is to provide
a competitive "up-to-spec" class where the cars are reliable and performance
potential is as even as possible. These rules are intended to control costs and
remove any performance advantage from the cars so that driving ability and
suspension set up are the greatest factors in determining race winners. This
class will be
referred to as the the BSX class and is
designed for time trial, driver education (DE) and autocross events.
BSX rules cater to those drivers that wish to use their cars for
both street and track use.NOTE: We
have added "NOTES" to these rules to help you better understand your options. We
have seen some spend a lot of money before they take their cars out on the track
which is not necessary - a luxury but not necessity. Remember this is an
"up-to-spec" so you can bring your bone stock car, plus required safety
equipment and run it just the way it is. Notes are NOT considered part of the
rules and should be evaluated as such.
General Rules
BSX Spec is an "up-to"
spec, you may run stock OR spec parts.
ALL BSX CARS MUST BE STREET LEGAL.
All parts must be factory stock from one of the eligible years, except where
otherwise noted. In general, modifications which improve aesthetics, access to
systems, safety or reliability are allowed and encouraged provided they offer no
performance advantage. There are no exceptions. No upgrade to any Boxster S
component is allowed unless specified in these rules.
ANY MODIFICATION NOT EXPRESSELY COVERED BY
THESE RULES IS PROHIBITED
MODIFICATION OF SPEC PARTS PERMITTED
NON-STOCK PARTS CAN HAVE NO POTENTIAL FOR AERODYNAMIC IMPACT
Eligible Models
1997-1999 Porsche 986
Boxster. 2.5 motor Part # M96.20
Safety
All
safety requirements are subject to the rules of the event sanctioning
body.
A 5-point or 6-point harness is recommended for all seats installed
in the car. 3" lap belts and 3" shoulder harnesses or a HANS specific 3-2-3
belt, and a minimum single 2" anti-submarine strap. Harnesses must be attached
either to the chassis using large backing washers, or to the roll bar/cage, but not directly to the seats or seat
rails.
Roll Bar/Roll Cage
All BSX cars must have as
minimum rollover protection the GSR Autosport GSR-BSX-001 or Brey-Krause R-3010
roll bar extensions bolted to factory equipment roll hoops and padded as
per sanctioning body rules.
Roll
cages are optional.
NOTE: We understand there is a desire and/or need to improve the safety
in the BSX class. It is for this reason that we have left roll cages as an
alternative. It is up to the sanctioning body to determine if the added roll
cage structure eliminates the requirement for the roll bar
extension.
Weight
Minimum
weight requirements must be met immediately following all timed sessions. The
choice of which systems/accessories to remove, in order to lighten the chassis,
is free. Batteries may be swapped for a lighter type, but must be securely
mounted in the stock location. Minimum weight includes driver. Spare tire may be
removed. Ballast to meet minimum weight must not exceed 50lbs. Ballast must be bolted to the floor of the passenger
foot well or in place of passenger
seat.
Minimum weight = 2950 lbs
including driver
Chassis
Seam welding of
the chassis is not allowed.
Engine
General
All engines and their
mechanical and electrical components must remain stock. No solid engine or
transmission mounts are allowed. Engine and transmission must remain in their
stock location.
Cooling System
Use of additives, such as
Redline Water Wetter is permitted. Radiator fans may be direct wired with a
switch.
Radiator
One additional radiator, placed in the
center of the grill area is allowed. Boxster S or 996 center radiator is allowed
as an addition only to the stock radiators.
Oil
Cooling
The factory oil cooling system must remain stock, except for
the following allowed modifications:
- An external oil cooler is allowed
- Upgrade to a Boxster S oil cooler
- Brey Krause deep sump oil pan
- Accusump oil accumulator is allowed
NOTE: We have seen many BSX cars run without any
additional cooling. Don´t feel that this is absolutely critical to get out on
the track. Monitor your temps and evaluate as needed.
Air Filter
No modifications to the factory engine air inlet or intake system. Drop in factory
size/style replacement air filters only.
Fuel Tank
and FillerMust remain in the stock
location.
Pulley/Belt SystemUnderdrive crank pulley
allowed and recommended. Minimum 4" diameter. No modification allowed to water
pump,power steering pump, alternator, idler pulleys etc. and all must be
operable and beltdriven.
NOTE: Most BSX cars we have
seen have not installed an underdrive pulley. Again, if you are doing a lot of
track days, something to consider to reduce stress on belt driven
components.
Computer Engine Management
SystemThe stock computer engine management system must remain stock.
No other engine management system may be added. No aftermarket chips are
allowed. No re-mapping or flashing of factory chips is
allowed.
Exhaust SystemAny muffler may be used. All
other exhaust components must remain stock. No
aftermarket headers are
allowed.
Transmission /
DifferentialTransmissionMay be rebuilt but must
retain stock gear ratios
Clutch
Any approved clutch disc and clutch cover (pressure plate) may be used.
Approved clutch kits,
pressure plates and clutch discs:
- Clutch Kit Sachs/Porsche - Part# 986 116 911 00/986 116 911 01 (For use with stock flywheel) Contains (1) clutch disc, (1) pressure plate and (1) release bearing.
- Sachs "Sport" Pressure Plate - Part #88 3082 999 754
- Sachs Clutch Disc "Sport" Rigid Hub w/ Organic Lining Higher Friction - Part # 88 1864 999 959
- Genuine Porsche Clutch Disc - Part# 987 116 014 00
NOTE: Stock replacement parts work fine. If you don't have any issues, don't bother replacing until you have an issue.
DifferentialMust remain stock.
ShiftersShort Shift kits are allowed but not
recommended
NOTE: The syncro gears in the stock transaxle are a bit delicate so the added abuse of very quick shifts isn't necessary a good thing over the long haul.
Suspension/Steering
ComponentsAll suspension components not otherwise listed must be
stock factory parts. All suspension components must be mounted in the unmodified
factory original mounting locations. No urethane bushings are
allowed.
Shock Tower BracesNo modification of the shock
tower is allowed.
Strut braces are not allowed.
Camber
plates and adjustable A-Arms are not allowed.
(Cars with camber plates grandfathered for the 2009 season must remove the camber plates for 2010.)
A-Arms
A-Arms must remain stock in BSX
class.
Springs and ShocksShocks: Bilstein PSS9 -
Part# F4-GM5-8847-H0 only. No in-cockpit adjustability. Stock valving only.
Bilstein PSS9 springs may not be changed.
All spring and shock
systems must mount in the factory original location only.
Sway Bars
- Front: H&R 70779 OR Porsche GT3 - Part# 996-343-701-90
- Rear: H&R 71779 OR Tarett Engineering 986 RSBA
Drop Links
Approved drop links:
- Front: Tarett Engineering #996FDLNK, Tarett Engineering GT3 "long links #EXTFDLNK or modified stock
- Rear: Tarett Engineering #996RDLNK or stock
(modified stock allows for a shortening of 2" for use with GT3 front sway bars)
Must mount to stock shock location.
Toe Links
- Rear: Stock or Tarett Engineering # 996TLNK
Ride Height
- Front: Minimum 90mm as measured at front cross of aluminum cross member (all parts and bolt heads)
- Rear: Minimum 90mm as measured at front-to-rear braces, near sway bar (all parts and bolt heads)
NOTE: Shocks and sway bars are the biggest performance upgrade you will make to your BSX car, but don't think you have to make this major investment before you head out to the track. Get out and get some seat time in stock configuration. Maybe add sway bars at some point. When you are ready to go all in, pony up for the shocks. Front stock drop links can be modified and stock rear drop links work fine without modification. Toe links are again a nice to have but not necessary.
Wheels and Tires
WheelsAny factory
or aftermarket cast aluminum rim
intended for use on the Boxster matching the original offset is
allowed.
Wheel weight must be equal to or greater than stock:
- Front 17x7 inch - 18.5lbs minimum - 55mm offset
- Rear 17x 8.5 inch- 20 lbs minimum - 48-50mm offset
Or (but not recommended):
- Front 16x6 inch - 50mm offset
- Rear 16x7 inch- 50mm offset
Steel bolts or lugnuts are required. Wheel spacers are not allowed. Hubs may be converted to studs in
place of wheel bolts.
Tires
Toyo
R888 or any DOT street tire with a UTOG tread wear rating of 100 or greater.
Max dimensions:
- Front: 225x45x17 or 205x55x16
- Rear: 255x40x17 or 225x50x16
NOTE: Tires are probably the first thing you want to upgrade to improve the performance of your BSX car. Street tires are not meant for the abuse of the track. A good set of track tires will add a lot of additional mechanical grip without having to make any permanent changes to your car - put them on to go to the track and take them off when you get home. Use your street tires for daily driving.
Brake System
Brake pads are
free.
Steel braided brake lines are allowed.
Brake dust guards may be
removed.
The emergency brake, lever and/or cables and all associated parts
may be removed.
Brake cooling systems are allowed, provided they use only air
to cool with. Air may be vented through the front air dam for brake
cooling.
Any stock-sized rotor is permitted. Cross drilling or gas slotting
of the rotors is allowed.
Brake calipers must remain completely
stock.
Battery
Stock location, min 10lbs.
Data Acquisition / In-car Timing Equipment Is allowed.
AppearanceThe class nomenclature of BSX shall appear on
each side and the rear of the car in 4" contrasting letters. Car numbers shall
be issued by the sanctioning club hosting the event. Numbers shall comply with
the rules of the sanctioning body.
Soft convertible tops and all associated
motors and assemblies may not be removed.
Air dams and bumpers must be either
stock or approved replica units. No carbon fiber is allowed.
Approved
front bumpers:
- Stock
- Stock with cutout for additional radiator
- Stock or replica Boxster S
- 996 Carrera 2 (same as found on US delivered 1999 C2 model)
Deck lids must remain stock.
Splitters / Side Skirts
GT3 style factory part# 996-505-986-91 or clone only.
Splitters may not extend forward of the front bumper, nor lower than 3" from the bottom of the front bumper. The front bumper must be located in the factory position and cannot be moved in any way. Factory or factory replacement side skirts allowed.
License plates, license plate frames, license plate lights, and insignias and emblems may be removed.
Hood pins are allowed and recommended. Stock hood latches may be disabled or removed.
All headlights and taillights must remain stock. Headlights may be covered.
Rear spoiler may be left in the upright position and motor removed.
Any exterior modification
that is determined to have no performance enhancing value is allowed. This
includes but is not limited to radiator inlet screens, side inlet scoops and
screens, ventilation ducts to brakes or to the passenger
compartment.
Interior
The driver or
passenger seats may be replaced with any seat suitable for competition,
including a racing-type bucket seat. Factory seat tracks may be modified,
reinforced or removed to facilitate replacement mountings provided they perform
no other function.
Factory dashboard instrument pod must remain intact. Additional gauges may be added.
Any steering wheel may be used except wood rimmed type steering wheels. Quick release steering hubs are allowed.
Factory airbags may be removed
but not recommended if vehicle will be driven on the street.
Factory engine cover must remain in the stock and latched position.
The driver’s side floor mat must be removed.
Passenger seat may be removed.
Engine cover carpet, front and reat trunck carpets may be removed.
All other interior items (floor carpet, door liners, etc.) must remain if not specifically allowed
removal.
NOTE: Remember, if you are thinking about eventually moving up to the BSR class, just about everything you do in the BSX class, other than most notably the roll bar extension, can be used in the BSR class so there is very little time and money wasted starting in BSX and moving to BSR at a later time.
Rules Revision Process
The Boxster Spec Racing Rulebook will be controlled by PCA and POC with hopes of ongoing cooperation that will result in a continued unified Spec. The two sanctioning bodies will receive input from the BSR Rules Committee through the Sanctioning Body Liaison.
The BSX Rules Committee will consist of a representative of every region wherein there are a significant number of BSX cars. Minimum BSX Rules Committee configuration: 1 builder, 2 drivers.
The Rules Committee will collect and assess rules change suggestions from the active drivers on an annual basis per the following guidelines:
April 1- May 31
Proposals for new rules or modifications to existing rules will be posted to a Rules Revisions forum on the Boxster Spec Racing website (boxsterspecracing.org). Access to this forum will require a special permission that will be granted only to Boxster Spec drivers and builders who have been active in the series within the prior twelve months.
June
Rules proposals and discussions will be reviewed and decided by the Rules Committee.
July 1
Rules change suggestions for the following season will be forwarded to the PCA/POC by the Sanctioning Body Liaison for consideration by the respective organizations.
October
The sanctioning bodies' decisions will be announced and posted to all available Boxster Spec websites. At any time during the competitive season, should there be a need for immediate rules change (spec part not available, over-looked loophole being exploited etc) the BSX Rules Committee shall meet, to rule on that issue and subsequently notify all Sanctioning Bodies of the rule amendment. Best efforts via email and website posts will be made to inform all drivers of any changes.