MRT 5-lug hub and brake adapters, BMW E30

MRT 5-lug hub and brake adapters, BMW E30

Adapters for a BMW E30 5×120 hub and brake conversion. Choose front hub/caliper adapters with or without ABS, rear caliper adapters or 180/185 mm parking-brake adapters.

Front construction and fitment

• For E36/E46 front hubs, BMW 31226757024. The original-type nut and dust collar fit the one-piece hub adapter.
• The brake-disc mounting face moves +17.5 mm relative to the original E30 position. Designed around E36/E46 wheel offsets to preserve the original scrub radius.
• CrMo steel hub adapters. Dual-pattern front brake adapters and spacers use AW-7075 T6 aluminium, with grade 10.9 or 12.9 fasteners.
• Fits E30 non-M struts, both 45 and 51 mm, with or without ABS. Not for E30 M3 or E30 iX front struts.
• Provides additional clearance between the brake disc, tie rod and lower-arm end. Compatible with MRT roll-centre / bump-steer / angle kits.

Manufacturer-listed front brake combinations

• 286×22 mm disc and caliper: E36 318i–328i or E46 316i–323i.
• 300×22 mm disc and caliper: E46 316i–328i.
• 325×25 mm disc and caliper: E46 325i–330i.
• 325×28 mm disc and caliper: E46 M3. Alternatively, an E46 M3 disc with an E36 M3 or E34 540i/M5 caliper.
• 345×28 mm disc and caliper: E46 M3 CSL. E36 M3 front brake discs are not compatible.

Rear construction and fitment

• Designed for Z4/E90 LCI rear hubs, BMW 33416752381. Mounting-face offset is +2.5 mm versus the original E30 position. The hubs require a 42x75x37 mm bearing.
• E30 applications require large-bearing trailing arms, such as those used on 325i and facelift ABS models. The manufacturer also lists E30 M3/iX, E36 Compact and Z3 non-M rear applications when hub and bearing requirements are met.
• Rear caliper adapters are machined CrMo steel. Select original-type dust shields and parking-brake shoes to match the chosen brakes.

Manufacturer-listed rear brake combinations

• 280×10 mm disc and caliper: E36 316i–325i or E46 316i–318i.
• 276×19 mm disc and caliper: E36 323i–328i or E46 316i–323i.
• 294×19 mm disc and caliper: E46 325i–328i.
• The 312×20 mm E36 M3, 320×22 mm E46 330i/d and 328×20 mm E46 M3 disc options additionally require the 180/185 mm parking-brake adapter.

Installation notes

E36/E46 non-M front caliper carriers require grinding for bolt-head clearance. With 325/345 mm discs, only minor carrier or strut-mount clearance work is normally required. The ABS option requires removing the original hub ring and pressing on the replacement.

At the rear, small 280 mm and 276 mm discs require grinding the trailing-arm upper mount using the adapter as a guide. The source gives both 18 and 19 mm thickness for the 276 mm disc, so check the combination against the drawing. E36 M3 shield holes require elongation, and E36/E46 caliper openings need widening.

Hubs and brakes must match the selected combination. This is an adapter package, not a complete brake system. MRT decals are included.

Product options

Option 1: Contents.

Installation instructions and drawings

• Adapter kit, front, Instructions, PDF
• Adapter kit, front, Assembly drawing, PDF
• Adapter kit, rear, Assembly drawing, PDF
• Tekninen vertailukuva / Technical reference 11