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Denso 671-8058 Spark Plug Wire Set
Denso 8mm Spark Plug Wire Set for Cadillac V8s
The Denso 671-8058 spark plug wire set is built for 1975-1976 Cadillac applications and follows the factory-style form, fit, color, and performance expected from an OE replacement ignition wire set. With 8mm insulation and silicone spark plug boots, it is a direct-fit choice for Cadillac Commercial Chassis, DeVille, Eldorado, and Fleetwood models.
Denso’s First Time Fit line is engineered to meet or exceed OE/OES standards in construction, making this wire set a practical option when replacing worn ignition leads on classic Cadillac vehicles.
Key Features
- 8mm ignition wire set for classic Cadillac applications
- Silicone spark plug boot material for heat resistance and flexibility
- Female distributor coil end terminal type
- 180-degree spark plug end boot design
- Female spark plug end terminal type
- Direct OE-style replacement from Denso First Time Fit
Product Details
Part number 671-8058 is a Denso spark plug wire set designed to match factory-installed wire sets in form, fit, color, and performance. The 8mm outside diameter supports a stock-style ignition setup, while the silicone boot construction helps maintain a secure connection at the spark plug end. This part is a strong match for owners searching for a 1975 Cadillac DeVille spark plug wire set, a 1976 Cadillac Eldorado ignition wire set, or a 1975-1976 Cadillac Fleetwood replacement wire set.
This part cross-references ACDelco 608M and NAPA Mileage Plus 6718058 for the same application.
Common Issues It Can Address
- Cracked or brittle ignition wires
- Misfires caused by worn wire insulation
- Hard starting from weak spark delivery
- Intermittent ignition performance on classic Cadillac V8s
- Loose or deteriorated boot connections at the spark plug or coil end
Installation Notes and Tips
Verify wire routing against the original layout before removal to preserve firing order and prevent crossfire. Confirm the female terminal ends and 180-degree spark plug boot orientation match the vehicle’s ignition configuration before installation. For best results, inspect plugs, distributor cap, and coil components at the same time so the new wire set can perform as intended.
Quality Assurance
Denso First Time Fit ignition wire sets are manufactured to OE-style standards and are intended to match factory-installed specifications for fit and performance. Part number 671-8058 is built for 1975-1976 Cadillac Commercial Chassis, DeVille, Eldorado, and Fleetwood applications.
| Brand | Denso |
| Part Number | 671-8058 |
| Position | 8mm |
| Spark Plug Boot Material | Silicone |
| Distributor Coil End Terminal Type | Female |
| Insulation Outside Diameter | 8.00 |
| Spark Plug End Boot Degree | 180 |
| Spark Plug End Terminal Type | Female |
| Spark Plug End Boot Quantity Straight | 8 |
This part fits 8 vehicles. Search below:
| Year | Make | Model | Position | Notes |
|---|---|---|---|---|
| 1976 | Cadillac | Commercial Chassis | N/A | 8mm |
| 1976 | Cadillac | DeVille | N/A | 8mm |
| 1976 | Cadillac | Eldorado | N/A | 8mm |
| 1976 | Cadillac | Fleetwood | N/A | 8mm |
| 1975 | Cadillac | Commercial Chassis | N/A | 8mm |
| 1975 | Cadillac | DeVille | N/A | 8mm |
| 1975 | Cadillac | Eldorado | N/A | 8mm |
| 1975 | Cadillac | Fleetwood | N/A | 8mm |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.