944
Challenge tECHNICAL SPECIFICATIONS
REFERENCE:
CAMS Online Manual
of Motorsport, Section 7, Group 2B Marque Sports
AUTHORITY:
This document was
approved by the 944 Racing Association Committee by circulation vote on
11Jan 2009.
ACTION:
This document is the
definitive Specification Document for cars competing in the aPorschaPart
944 Challenge.
Porsche 944 2.5L SOHC
To be read in conjunction
with the CAMS Manual of Motor Sport and the Group 2B Technical Regulations
for Marque Sports Cars
Porsche 944 Challenge
vehicles (as
per “Porsche 944 Models Dimensions and tolerances” WKD 423 320)
are subject to all the restrictions and freedoms
contained within the Group 2B, Marque Sports Technical Regulations, save
where additional restrictions are imposed by the present specifications.
Where any discrepancy exists between any restriction, dimension or
component specified in the present document and the Group 2B Technical
Regulations, that specified in the present document shall take priority.
Unless specifically permitted, no modifications are allowed to the
standard vehicle.
For convenience, the
general section numbering in the present document is intended to follow
that of the Group 2B Technical regulations.
1 Definition
1.1 The VIN prefix
used by the manufacturer for identification of eligible vehicles is:-
Porsche 944, VIN prefix
WPOZZZ94Z or WPOAAO94
1.2 Cars with
identification plates with other than the above codes are not necessarily
prohibited from use, provided that the specifications of the car are in
compliance with those of the cars identified in 1.1.
1.3 Where a Maximum
or minimum value is specified in this document, that value shall be
absolute, and no tolerance shall attach.
2 Regulations
No Additional
restrictions.
3 Bodywork and Dimensions
3.1 Seam welding of
the body shell is not permitted.
3.2 Rear bumper bar
or a fibreglass replica must be retained.
3.3 Front
bumper/fascia must be either standard, or a fibreglass replica of that
fitted to the 944 turbo model. Front air dams may not be added.
3.4 The rear
spoiler must be either standard, or a fibreglass replica thereof.
Additional rear spoilers / wings must not be added.
3.5 The rear hatch
must be the retained standard glass component. Additionally, rear hatch
restraints must be fitted to each side of the hatch, either in addition
to, or replacing, the standard latch mechanism to prevent the hatch
opening more than 250mm.
3.6 Body Width
The body width is to be a
maximum of 1740 mm, as measured above the centre line of the front and
rear axles. Wheel arches may not be flared.
3.7 Minimum Racing
Weight 1100 kg
3.8 Front
Lights If the standard pop-up headlights are removed, they must be
replaced by either 2 or 4 rectangular lights mounted in the driving light
recesses of the front bumper.
Dimensions of the lights Minimum width 125mm
Minimum height 55mm
Minimum power 55W
3.9 Rain Lights: A
20W globe must be fitted into both of the rear combination lamps in the
position normally used for fog lamps. The extra globes must illuminate in
conjunction with the parking lights
4 Engine
The complete engine
assembly must remain standard and unmodified, save as specified in 4.1 to
4.14 below. The cylinder block
must bear one of the following casting designations:
M44.01 to M44.10, M44.40,
M44.50 to M44.52
4.1 Blueprinting
and balancing of components is permitted.
4.2 Removal of
unused ancillary components mounted on the engine is permitted.
4.3 The fuel rail
may be replaced by one of free design.
4.4 Alteration of
valve seat geometry is permitted.
Removal of piston
material to increase valve clearance is permitted.
The maximum throat
diameter of the inlet valve seat insert shall be 39.80mm.
The maximum throat
diameter of the exhaust valve seat insert shall be 34.90mm.
The thickness of the
cylinder head (“A” dimension) is not restricted.
4.5 Crankshaft:
Cross-drilling permitted only to aid lubrication.
4.6 Camshaft
The camshaft may be either type 155.05 or 155.09.
A
type 155.05 cam may be modified to type 155.09 specifications or a new
billet ground to type 155.09 specifications by the approved supplier.
The approved supplier is: Clive Cams
Factory 4, 35-37 Clyde St
Ferntree Gully 3156
Ph. 03 9758 5977.
Each re-ground camshaft shall be stamped by the supplier with an
identification number and grinders make.
The keys and keyways of
the standard camshaft timing sprocket may be modified provided camshaft
timing remains standard. The timing belt cover may be removed or replaced
by a custom made part.
4.7 Exhaust pipe: The exhaust is free from the first flange joint.
4.8 The following
items may be replaced by mechanically and functionally identical
substitute components.
Pistons and
rings
Bearings
Valve
springs
Piston pins
Bolts and fasteners
Gaskets
Valves
Spark plug leads
Ignition Coil
Alternator
Electrical Wiring
4.9 The following
specifications shall apply to engines.
Bore 100.50 mm Maximum
Stroke 78.9 mm ± 0.1
Compression Ratio
11.5:1 Maximum
4.10 Throttle body:
The throttle cam profile may be modified.
4.11 Engine Control
Unit (ECU). The controlled ECU is the Wolf 3D 944 Challenge unit,
available from Advanced Engine Management Systems. The ECU and sensors
supplied with
the Wolf engine management system
must be used. The maximum allowable engine RPM is
6500. It is the entrant’s responsibility to demonstrate compliance with
the RPM limit as requested.
From 01/01/08, the ECU is
unlocked, and the crank angle may be detected in any position using
sensors supplied.
4.12 The following
minimum weights shall apply:
Crankshaft
(bare) 23.5 kg
Connecting rod/screws/cap/nuts 820 g
Inlet
valve 96 g
Exhaust
valve 94 g
Clutch assembly
including fasteners 10.2 kg
Piston/rings/piston
pin/clips 710 g
4.13 The ř70mm tube
with air temp sensor (supplied with the Wolf ECU) must replace the air
flow meter and be installed in the same position. The Engine Air Intake is
free upstream of ř70mm tube.
4.14 The fuel
pressure regulator(s) may be replaced by one of free design
5 Piping and
Fuel Tanks
No additional
restrictions
6 Cooling System
6.1 Radiator:
Custom radiators may be used subject to the following restrictions:
The width and height must be no
greater than the standard radiator
The thickness of the core shall be no
greater than 55mm
6.2 Ducting: Must
not protrude below the front bumper and must be through existing body
openings only, which includes driving light recesses.
6.3
The cooling system header tank may be
relocated and/or replaced with a non-standard tank of similar capacity. An
additional hose may be added between the header tank and the cylinder
head.
7. Transmission
to the Wheels
7.1 Gearbox and
Final Drive: The gearbox/final drive assembly shall be Porsche
944 Type 016J or 016K (Identification Code 5Y or 5S or ASG only), in
unmodified form. Only the following ratios are permitted.
1st 3.6000:1
2nd 2.1250:1
3rd 1.4583:1
4th 1.0714:1
5th* 0.8286:1 (016J) or 0.7297:1 (016K)
Rev 3.5000:1
*Either 5th gear ratio may be installed.
7.2 Differential: Limited slip or locked
differentials are not permitted.
7.3 Final Drive
Ratio: The only permitted ratio is 3.8890:1
7.4 Gear linkages:
The original gear selector lever and its pivot point must be retained.
7.5 Cooling of
lubricants: No additional cooling of gearbox/final drive/differential
lubricant is permitted.
7.6 Tailshaft and Driveshafts: These must be
standard components.
7.7 Bearings,
gaskets and seals may be replaced by non genuine components provided that
they must be mechanically and functionally identical substitutes.
8 Suspension and Steering
8.1 Front
Suspension: The control arm inner pivot/mounting position may not be
relocated. Stub axles and hubs must remain standard.
8.2 Rear
Suspension: Control arms must be standard, but may be of either
factory alloy or steel variants. The damper mounting point and spring seat
on the steel arms may be modified to match those of the alloy arm. The
control arm and spring plate pivot/mounting points must remain as
standard. The spring plate must remain standard.
8.3 Suspension Dampers: Canister adjustable shock
absorbers are not permitted.
8.4 Suspension
Bushes: Elastomeric suspension bushes may be replaced with mechanically
identical elastomeric bushes. The functional volume of the elastomer
component must be at least 90% of the equivalent volume of the original
bushing.
8.5 MacPherson strut top mounts: Must be as
standard.
8.6 Suspension
brace: No additional suspension brace between the suspension top
mounts is allowed.
8.7 Anti-sway bars:
The anti-sway bars may not be adjustable by the driver seated in the
normal driving position.
8.8 Wheel
Alignment: The maximum permitted front wheel castor angle is 3°.
8.9 Wheel track:
Maximum Front 1500mm
Maximum Rear 1480mm
(See CAMS Manual for measurement method)
Wheelbase: Maximum 2400 mm
9.0 Brakes
9.1 The entire
braking system must be retained in unmodified form, except as specified in
9.2 to 9.4 below
9.2 Freedom is
granted in relation to brake lines caliper seals, hoses and fluid. A brake
proportioning valve, which must not be adjustable from the normal driving
position, may be fitted into the rear brake line.
9.3 Brake pads:
Only Specified brake pads may be used both front and rear. These must be
supplied by “aPorschaPart”, Race Brake Compound No 6.
9.4 Brake disks:
Brake Disks may be subjected to slotting and/or cross drilling.
10. Wheels and Tyres
10.1 Wheel size: The maximum rim size is 15” x 8” (front
and rear).
10.2 Tyres: Yokohama
A048R 225/50R15 tyres must be used.
Removal of tread material
by Buffing and/or Grooving is not permitted
11. Cockpit and Driver’s Compartment
11.1 Pedals: The
pedal box, and the position of the pivot points in the pedal box must
remain as standard.
11.2 Console: Either
the standard console over the transmission tunnel, or a fibreglass replica
thereof must be retained.
12. Safety Structures
12.1 The Safety Cage must not extend outside the cockpit.
13. Fuel
13.1 The fuel to be
used in competition is JFP102 Racing Unleaded purchased at the event. No
additives of any kind are permitted.