Standard Ignition Distributor Vacuum Advance P/N:VC-257

Keep spark timing responding to engine load with the Standard Ignition distributor vacuum advance VC-257. This vacuum advance control uses engine vacuum to advance ignition timing as driving conditions change. It is listed for the 1977 Chevrolet Monza, 1977 Chevrolet Vega, 1977 Oldsmobile Starfire, 1977 Pontiac Astre and 1977 Pontiac Sunbird. See the Buyer's Guide tab for engine details.

• Precision calibration: Calibrated to provide the correct ignition advance.
• Leak tested: Units are tested at 30HG maximum vacuum to check that they do not leak.
• Quality control: As a global manufacturer of original equipment ignition products, Standard Ignition maintains quality control across the manufacturing process, from components to finished product.
• Ignition heritage: Standard Ignition has served the automotive aftermarket since 1919 and focuses on quality and broad coverage for ignition needs.

A vacuum advance works with the distributor. Engine vacuum acts on a diaphragm inside the unit, which advances ignition timing under light load. As vacuum drops, timing is allowed to return. Signs this part may need replacing include hesitation or sluggish part-throttle response, reduced fuel economy, or a diaphragm that no longer holds vacuum. Other ignition or vacuum faults can cause similar symptoms, so diagnose the cause before replacing. If a failed vacuum advance is the cause, VC-257 replaces it.

Interchange: 19110664 · V404 · DV1761 · VC1848 · 1973601