Part number 4B1972HC-STD
ACL Race Series with Calico CT-1 coating connecting rod bearings
Honda - 2.0 2.4 (K20A2, K20Z1, K24A, K24Z1)
| Sizes | STD, .025, .25 |
| Oil Clearance | Standard |
| Half Type | Identical Halves |
| Material | Tri-metal Hardened steel backs |
| Min. Std Shaft Size | 1.889in / 47.98mm |
| Max. Std Shaft Size | 1.8898in / 48mm |
| Min. Std Tunnel Size | 2.008in / 51.004mm |
| Max. Std Tunnel Size | 2.0088in / 51.024mm |
| Max Wall at Crown | 0.0591in / 1.5mm |
| Max Overall Length | 0.6063in / 15.40mm |
| Weight | 0.12 |
| Notes | 0 |

| ENGINE BEARINGS | ||
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CON ROD BEARING SET |
|
| Part# | ||
| 4B1972H |
4B1972HX |
|
| Sizes | STD, 025, .25 | STD |
| Oil Clearance | Standard | + 0.001" Extra |
| Half Type | Identical Halves | |
| Material |
Tri-metal Hardened steel backs |
|
| Min Std Shaft Size |
1.889in / 47.98mm |
|
| Max Std Shaft Size |
1.8898in / 48mm |
|
| Min Std Tunnel Size |
2.008in / 51.004mm |
|
| Max Std Tunnel Size |
2.0088in / 51.024mm |
|
| Max Wall at Crown |
0.0591in / 1.5mm |
0.0585in / 1.487mm |
| Max Overall Length |
0.6063in / 15.40mm |
|
| Notes | ||
|
Diagram |
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|

| ENGINE BEARINGS | ||
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MAIN BEARING SET |
|
| Part# | ||
| 5M1959H |
5M1959HX |
|
| Sizes | STD, 025, .25 | STD |
| Oil Clearance | Standard | + 0.001" Extra |
| Half Type | Upper & Lower | |
| Material | Tri-Metal | |
| Min Std Shaft Size |
2.1646in / 54.98mm |
|
| Max Std Shaft Size |
2.1654in / 55mm |
|
| Min Std Tunnel Size |
2.3228in / 59mm |
|
| Max Std Tunnel Size |
2.3236in / 59.02mm |
|
| Max Wall at Crown |
0.0788in / 2.002mm |
0.0783in /1.989 |
| Max Overall Length |
0.7874in / 20mm |
|
| Notes | ||
|
Diagram |
![]() |
|

| Sizes | STD, .025, .25 |
| Oil Clearance | Standard |
| Half Type | Identical Halves |
| Material | Tri-metal Hardened steel backs |
| Min. Std Shaft Size | 1.889in / 47.98mm |
| Max. Std Shaft Size | 1.8898in / 48mm |
| Min. Std Tunnel Size | 2.008in / 51.004mm |
| Max. Std Tunnel Size | 2.0088in / 51.024mm |
| Max Wall at Crown | 0.0591in / 1.5mm |
| Max Overall Length | 0.6063in / 15.40mm |
| Weight | 0.12 |
| Notes | 0 |