1991 GEO Storm GCI tire and wheel sizes, bolt pattern and tire pressure

Bolt pattern 4x100 on every 1991 trim.

Tires for the 1991 GEO Storm GCI

Sizes most trims come with first. Open your trim below for its exact size.

205/50R15 Best-rated standard on 1 trim

Check price on Amazon · 205/50R15
205/45R16 Best-rated optional on 1 trim

Check price on Amazon · 205/45R16
215/40R16 Best-rated optional on 1 trim

Check price on Amazon · 215/40R16

Also listed: 225/35R17

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Trims sold in 1991: 1
Generation: GM R
Other years: 1990
1991
1992
1993
All years (1990–1993)

1 trim sold in 1991

Open a trim for its tire and rim sizes, bolt pattern and tire pressure.

GEO Storm GCI GM R

1990–1993 1 trim

Storm GCI 1.6i 130 hp · I4 205/50R15 84H 4 fitments

Generation: GM R · 1990–1993
Power: 130 hp
Engine: I4, Petrol
Center bore: 56.1 mm
Bolt pattern: 4x100
Thread: M12 x 1.5

Check price on Amazon · 205/50R15 Wheels 15x6.5 ET45 · 4x100 · 56.1 mm on Amazon

Tire size	Rim size and bolt pattern	Pressure, psi
205/50R15 84H	Rim 15x6.5 ET45 4x100	30 psi
205/45R16 85V	Rim 16x7 ET42 4x100	33 psi
215/40R16 85V	Rim 16x7 ET40 4x100	33 psi
225/35R17 83W	Rim 17x7.5 ET38 4x100	36 psi

How to read 84H: 84 is the load index (up to 1,102 lb / 500 kg per tire) and H the speed rating (up to 130 mph / 210 km/h). ET45 is the wheel offset: how far the mounting face sits from the rim centre, in millimetres. Compare offsets in the wheel offset calculator.

What these columns mean

Rim size: Rim diameter × width in inches, and the factory offset (ET) in millimetres, e.g. 18x7.5 ET25.
Bolt pattern (PCD): Number of studs and the diameter of the circle they sit on. It must match exactly.
Center bore: Diameter of the hub hole. Larger aftermarket bores need hub-centric rings.
Pressure: Recommended cold inflation pressure for that axle, in psi.
Thread size: Lug bolt or nut thread — needed when buying aftermarket fasteners.