Subject: Summer Tire And Wheel Rim Summary Models: 912/911/All Carrera/911 Turbo ALL

Bulletin Number: 85 – 06

Tires tested for Porsche must fulfill a wide range of requirements.

For example:

• Service life
• High speed strength
• Handling on wet and dry road surfaces
• Adaption to vehicle design
• Comfort
• Rolling noise
• Wear

Listed below are tires and matching wheel rims sizes recommended by Porsche for types 912, All 911, Carrera and Turbo:

Other summer tires and wheel rim combinations are not approved by Porsche.

Notes on Pirelli P 6 tires

Three different versions of P 6 tires have been produced:

A – no special markings

B – cross in circle below size code

                215/60 VR 15

Always use only version C

Listed below are tires and matching wheel rim sizes approved by Porsche in past years. These tires are no longer tested by Porsche:

Note for Dunlop SP Sport Super tires

Dunlop SP Super Sport D 1 and D 4 tires must NOT be mixed on one car, either independently or by axle.

The D 1 version is still available, but in limited quantities only. If fitting a complete set of new tires, conversion should be o the D 4.

New tire instructions

Always use tires of the same make, type and size.

When changing tires of only one axle set, new tires should be mounted on wheels of front axle.

If replacing only one tire of an axle set, the difference in tread depth between tires must not exceed 30%.

General Installment Instructions

Always use new rubber valves, Part No. 900.265.001.50, when replacing tires.

Always coat tire beads with rubber lubricant when mounting tire on rim.

Work sequence

• Install new valve stern and remove insert
• Install tire on rim and inflate to 4.0 bar (60 psi)
• Ensure tire is seated on rim
• Install valve stern insert and inflate tire to correct pressure.

Tires and tubes

Do not use tubes and tires of different makes.

Tubes are not available for series 50/55 tires.

Tubeless tires should only be mounted with tubes in an emergency situation.

When installing tubes with steel valves make sure that the valve is screwed in only after the tire has been inflated. Do not twist the valve.

If necessary, 215/60 R 15 tubes fitted with steel screw valves (Pirelli or Dunlop only) can be used for the installation of 185/70 VR 15 tires on 7J x 15 rims. On pressure cast rims with a cast valve boss, the cover or nut of the bottom venting ring can be removed to ensure sufficient thread length for installation of the screw valve. It is essential to install the venting ring itself so that air can escape from between the tube and rim.

The 7” and 8” inch Porsche rims must be fitted with valve supports, Part No. 911.361.561.00 and 01, to avoid lateral stress on rubber valves caused by the design position of the valve bore.

The 7J x 15 pressure cast rims (From ATS) will sometimes have a special cast boss in the area of the valve bore which provides safe valve support.

On rims which have this cast boss, the wall thickness at the valve hole will be so large that when installing tubeless tire valves the 3 mm wide bead ring must not be pulled through –  as is common for steel rims. Pulling the valve bead through would cause excessive expansion of the valve.

Example: 6J x 15 H2

6=rim width in inches

J=flange version

X=well base

15=diameter in inches

H2= double hump

Tubeless tires must be mounted without tubes only on rims with double humps. An appropriate tube would have to be used with these tires when mounting earlier rims.

When necessary, a tubeless tire may be matched with a tube tire on the same axle if make, size and type are identical.

Rims with double humps were introduced on the 1976 models.

Original Porsche Rims can be identified by the Porsche part number on the rim:

901.361.xxx.xx – rim without humps

911.361.xxx.xx – rim with double humps

X=digits for internal designation of version and paint.

Pressure cast rims are not always sufficiently airtight because of the rougher structure. Consequently, they are suitable for use with tubeless tire only after some appropriate testing. Beginning with some 1976 models, Porsche pressure cast rims are tested for gas leaks and are approved for use with tubeless tires.

Note

Always use self-centering rims on vehicles with selfcentering tubes.

Use only steel nuts on steel rims.

Matching tires with forged,  perforated disc wheel rims,

Part No. 911.361.020.43 (6J x 16)

Part No. 911361.020.44 (7J x 16)

Part No. 911.361.020.45 (8J x 16)

Tires and perforated disc wheel rims are matched during vehicle assembly to minimize radical

Matching Procedure

• A machined depression on the rim wall of the perforated disc wheel rim marks the point of highest radial run-out.
• A red locking dot is pasted on the outside of the rim
• Tires are marked with a green dot
• Align red and green dots when installing tire on rim.

• Dots must be within 30 mm (1 3/16 in.) of each other.

Note

If the red locating dot is missing, mark the location of machined depression with chalk or tape before installing tire.

Aluminum Wheel Nuts

Aluminum wheel nuts require special car.

Before installing

• Lubricate threads and shoulders of aluminum nuts with Optimoly HT, Part No.  999.917.728.00 (Optimoly HT does not affect tightening toque)

• Torque nuts to 130 Nm (96 ft. lb)

Note

Tighten and loosen aluminum nuts with a socket that graps the entire depth of nut

Break in time for new tires

New tires have a vulcanization skin that can cause poor vehicle handling. Handling characteristics improve measurable during the tire break-in period of 600 miles (1000 km).

Vehicle handling characteristics should not be evaluated immediately after the replacement.

Driving conservatively during the first 600 miles (1000 km) will help to maximize tire life.

After the break-in period, check wheel balance.

Balance Weights

Use only single balance weights, a maximum of 40 grams each, on 15 inch wheel rims on vehicles with brake pad wear indicators (standard on 911 Carrera/911 Turbo as of 1984 Model Year) Sufficient clearance cannot be guaranteed if larger weights are used.

Obtain even tire wear by rotating tires after 3000 miles (5000 km).

Recommended tire rotation sequence

(not possible on Types 911 SC, Carrera and 911 Turbo)

Tire Pressures

Measure tire pressure only when tires are cold. Air pressure increases as tires get hotter and must not be decreased.

Collapsible spare wheel: 2.2 bar (32 psi)

*2.5 bar (36 psi) specified for rear wheels of 911 Carrera from 1984 Model Year.

Conditions leading to slow air loss or structural damage

• Damage to bead during installation
• Installation damage from excessive expansion of bead core; tire could part from rim.
• Installation damage to inside of tire; could cause loss of air or ply separation.
• Punctures from foreign objects (nails, glass, rocks, etc.); moisture can cause rust at puncture
• Squeezing damage (from rubbing against curb or slipping off road shoulders)
• Cuts in tire (especially sidewalls).
• Damage from underinflation.

Damage that impairs true-running of wheels

• Flat spots from standing. Under high temperature conditions. Tires may develop flat spots on the contact surfaces during long period of standing. Driving the car should correct this condition.
• Uneven wear from damaged suspension parts or misalignment. Checking/correcting wheel alignment is necessary along with the replacing of damaged parts.

• Uneven wear from improper balancing. Correct balancing must be performed before damage occurs.
• Flat spots from locked wheels while braking. This damage usually remains noticeable and cannot be repaired.

When checking tire pressure, also check condition of tires. Look for uneven tire wear, damage to tires and rims and damage to suspension parts.

Porsche recommends checking wheel alignment following the first 600 miles (1000 km) of driving, or after any repairs to the suspension system.

Note

Repairing tires with pressurized sealants or tubes or not acceptable.

Storing tires

Rubber ages and is sensitive to certain substances. Ozone, fuels, oils, greases and solvents have a damaging effect.

Storage information

• Store tires indoors when cool and dry. Temperatures between – 10 degrees Celsius +20 degrees Celsius (14 degrees Fahrenheit and 68 degrees Fahrenheit)
• Clean tires with water before storing.
• Store tires in a dark room
• Store tires on rims and inflate to higher pressures.
• Do not store tires near heat radiators, electrical equipment, fuels, lubricants, solvents or chemicals.
• Do not store tires in direct sunlight or under constant fluorescent lighting. Avoid blue light protection paint on windows.
• Do not store tires by suspending on hooks or in stacks.

Note

The assumption that tires are more wear resistant after aging is not valid.

VR rated tires should not be used if older than 6 years.

Age can be determined by the last three digits of the DOT code on the tire sidewall.

For example:

If the last three digits are 193, the tire was manufactured in the 19^th week of 1983.

Wear

Excessive, rapid tire wear is usually attributed to driving habits.

Almost all tires have tread wear indicators specified for the U.S..

The tread wear indicator is a ridge across the thread base at 6 points on the circumference of the tire.

Tread wear indicators

The ridge has a height of 1.6 mm. When tread wear reaches this point, the ridges become visible. The appearance of the wear indicators signals the need for tire replacement.

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