This solid rear brake disc is a precision-machined replacement for Austin Healey Big Healeys that have been converted from factory rear drums to rear discs. It suits cars with the 5-stud rear axle, restoring stable, repeatable braking performance where existing conversion hardware is already fitted.
Short answer: Late BN1 (from chassis 221536) through BJ8 with the 5-stud rear axle and an existing rear disc conversion.
Exclusions: Early BN1 (to 221535) with 4-stud axle; any car still on factory rear drums; cars with non-standard hub/axle arrangements. Confirm axle type and that your car already has a rear disc conversion before ordering.
Sold individually. Two discs required per axle and should be replaced as a pair.
Note: Dimensions and bolt pattern match common Big Healey 5-stud conversion layouts. If a non-standard kit is fitted, check measurements before purchase.
Removal of the rear hub/disc assembly is required. Follow workshop-manual torque figures and shimming procedures. After fitting, bed in new discs and pads gradually. Check wheel and caliper clearance, rear hoses, and fluid condition (use the brake fluid grade specified for the rest of your system, typically DOT 4 unless your system specifies otherwise). Replacing discs on an existing conversion normally does not alter brake balance; if converting from drums, use a complete engineered kit to maintain correct bias.
Austin Healeys were factory-equipped with rear drums. For cars already converted to a rear disc setup, this disc provides a dependable, correctly machined service replacement—avoiding the inconsistencies of worn or re-skimmed components.
Planning a full conversion rather than servicing an existing setup? Consider the Rear Disc Brake Conversion Kit for BN1–BJ8 with alloy calipers, brackets and parking-brake linkage, engineered for balance and fitment.
Late BN1 (from chassis 221536) through BJ8 with the 5-stud axle and an existing rear disc conversion. Early BN1 (4-stud) is not compatible.
No. Big Healeys left the factory with rear drums. This disc is for cars that have been converted to rear discs, or for use within a complete conversion kit.
Yes, if it is a late BN1 from chassis 221536 and the car already has a rear disc conversion. Early BN1 with 4-stud axle is excluded.
Yes. Discs are sold individually and should be replaced in pairs to maintain balanced braking.
For new conversions, brake bias may need tuning; use a complete kit engineered for correct balance. As a like-for-like disc replacement on an existing conversion, additional bias changes are typically not required.
This disc sits within the conversion hardware; compatibility with wheel type depends on the kit used. Most engineered kits accommodate both wire and steel wheels; check caliper clearance.
5 stud rear axle only