Balancing and wheel alignment
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Information pertaining to correct wheel alignment and tyre balancing. This is not designed to be a complete list, but some of the most important things. The equipment and exact details are relevant when a "Porsche" trained engineer who uses the correct procedures does it.

Labour - Alignment

Adjust:
Front suspension
toe-in: 0.6 hours

Align:
Front wheel: 2.0 hours
Rear wheel: 1.2 hours

Specifications
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Wheel Alignment Specifications:

The following values apply to curb weight in accordance with car with full fuel tank, spare tyre and tools.

Front Axle:
Toe-In (un-pressed) 0°10' ±5'
Track difference angle at 20°lock -40' to -1°50'
Camber 0°±10'
Max. Difference LH to RH 20'
Caster 2°30' (+30'/-15')
Max. difference LH to RH 30'

Rear Axle:
Toe-In per wheel 0°10' ±10'
Max. difference LH to RH 10'
Camber -1°±20'
Max. difference LH to RH 30'

Alignment Note
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Accurate front axle height adjustment is critical to toe-in, camber and caster adjustments. Ensure tyre pressures are at their specified values, fuel tank is full, spare tire is in place and a weight approximately the same as the driver, positioned on the driver's seat.

Camber
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Camber adjustment is made by loosening joint between spring strut and trailing arm, then turning camber eccentric.

Toe
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Adjust toe by moving trailing arm in slots of spring strut Adjust camber by turning eccentric bolt on lower strut mounting. On models with steel control arms, adjust caster by moving rear of suspension control arm from side to side. On models with aluminium control arms, adjust caster by loosening self locking nuts and turning caster eccentric until caster is within specifications, then torque nuts to 62 ft. lbs.

Rear Axle Height
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Rear vehicle height can be adjusted on two piece spring plate, without removal of torsion bars. If spring plate angle is as specified, vehicle height will be correct

Torsion Bar
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If the torsion bar is reset by one spline at its inner end, a 9° change is obtained. If the radius arm is reset by one spline at the outer end of the torsion bar, a change of 8 3/20°is obtained. This arrangement allows a change of 5/6°if the torsion bar and radius arm are positioned towards each other.

Position a bubble protractor on the lower edge of door sill. Rotate bubble level carrier on VW 261 or an equivalent protractor to specified torsion plate angle. With torsion plate cover removed, position protractor on torsion plate. Lift the plate enough to remove play from splines. According to angle measurement at door sill, if front of vehicle is lower than rear, add door sill measurement to torsion plate value. If rear of vehicle is lower than front, subtract door sill measurement from torsion plate value.

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In order to obtain a true wheel/tyre balance on the Porsche wheels (as determined by the vehicle hub), spin balancing of the wheel/tyre assembly around its true axis is required.

The centering of the wheel/tyre is accomplished by using the following special wheel balancing adapter and pressure cup.

Description:
Mag Wheel Pressure Cup
Basic Collet
Expanding Collet

These special wheel balancing adapters are used with the 17 inch and 18 inch wheels used on certain Porsche Models. This system can be used for 15 and 17 inch wheel/tires when balancing is performed on a stationary balancing machine.

Tools - Wheel Alignment Equipment
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Porsche through co-operation with the Hunter Engineering Company, gives its recommendation of the Hill and J111 computerised wheel alignment systems for all Porsche models. In all applications, the selected 111 models (C-J) must be configured for four-wheel alignment only.

I HOPE that finally this lays to rest all the rumours about alignment/balancing.

If your happy with a £20 tweak, fine, but don’t say it's been done properly !

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