Enginetech BC104J.020 is a 0.020 undersize main bearing set for 1963-1976 Pontiac 6.9L-7.5L 421-455ci V8 engines.
Important Notes:
- Sized for crankshaft main journals machined .020 inch undersize. Measure journal diameter before installation - installing on the wrong journal size will cause immediate clearance failure.
- Always replace main bearings as a complete set. Never mix new bearings with used bearings - uneven wear and clearance differences will cause premature failure.
| Part Number | BC104J.020 |
| Bearing Size | 0.020 Undersize |
| Quantity Per Set | 5 main bearings per set |
| Engine | 6.9L-7.5L 421-455ci V8 |
| Year Range | 1963-1976 |
| Makes | Pontiac |
| Country of Origin | US |
| Weight | 2.0 lbs |
| UPC | 707473000000 |
| OEM Cross-Refs | ACL:5M667P, FEL-PRO:4221M, MAHLE:MS-667P |
Complete main bearing set covering all main journals for the V8 application - one set required per engine.
Fitment:
- 1963-1966 Pontiac Bonneville 6.9L 421ci V8
- 1963-1966 Pontiac Catalina 6.9L 421ci V8
- 1963-1966 Pontiac Grand Prix 6.9L 421ci V8
- 1963-1966 Pontiac Star Chief 6.9L 421ci V8
- 1967-1969 Pontiac Bonneville 7.0L 428ci V8
- 1967-1969 Pontiac Catalina 7.0L 428ci V8
- 1967-1969 Pontiac Executive 7.0L 428ci V8
- 1967-1969 Pontiac Grand Prix 7.0L 428ci V8
- 1970-1970 Pontiac Bonneville 7.5L 455ci V8
- 1970-1970 Pontiac Catalina 7.5L 455ci V8
- 1970-1970 Pontiac Executive 7.5L 455ci V8
- 1970-1970 Pontiac GTO 7.5L 455ci V8
- 1970-1970 Pontiac Grand Prix 7.5L 455ci V8
- 1970-1970 Pontiac LeMans 7.5L 455ci V8
- 1970-1971 Pontiac Bonneville 7.5L 455ci V8
- 1970-1971 Pontiac Catalina 7.5L 455ci V8
- 1970-1971 Pontiac GTO 7.5L 455ci V8
- 1970-1971 Pontiac Grand Prix 7.5L 455ci V8
- 1970-1971 Pontiac LeMans 7.5L 455ci V8
- 1971-1971 Pontiac Bonneville 7.5L 455ci V8
- 1971-1971 Pontiac Catalina 7.5L 455ci V8
- 1971-1971 Pontiac Firebird 7.5L 455ci V8
- 1971-1971 Pontiac GTO 7.5L 455ci V8
- 1971-1971 Pontiac Grand Prix 7.5L 455ci V8
- 1971-1971 Pontiac Grand Safari 7.5L 455ci V8
- 1971-1971 Pontiac Grandville 7.5L 455ci V8
- 1971-1971 Pontiac LeMans 7.5L 455ci V8
- 1972-1972 Pontiac Bonneville 7.5L 455ci V8
- 1972-1972 Pontiac Catalina 7.5L 455ci V8
- 1972-1972 Pontiac GTO 7.5L 455ci V8
- ...and 16 additional applications
Enginetech main bearings are engineered to OEM specifications, drawing on over 40 years of engine rebuilding expertise to deliver the precise clearance, crush, and eccentricity required for long-term durability under both stock and moderate-performance loads. Each set is application-specific: materials, wall thickness, oil clearance, and surface finish are all matched to the crankshaft main journal geometry and operating loads of the engine family it serves. Main bearings are a wear component and must be selected to match the crankshaft main journal size - bearings sized for standard journals will not seat correctly on undersize-machined journals and vice versa, so verify your journal measurement with a precision micrometer before ordering or installing. Always replace main bearings as a complete set. Mixing new bearings with used bearings produces uneven oil clearance across the crankshaft and accelerates wear on the freshly installed bearings - the small cost of a complete set is insurance against premature failure on the bearings you just paid to install. Enginetech documents every set with clear application-specific notes, journal-size designation, and cross-references so the right part lands on the bench the first time.
WARNING: This product can expose you to chemicals including lead and nickel, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
