Overview
MSD's spark plugs are engineered to improve the efficiency of the combustion process to create the most power possible combined with increased durability. The center tip of the plug is made from iridium to promote the best spark and increase resilience. A proprietary ceramic material enhances the dielectric strength of the plug housing forcing the spark, even under extreme cylinder pressures, to jump across the plug gap to the ground electrode. This electrode is machined to expose more spark to the incoming gases to promote the most effective combustion event possible.
Features:
- Proprietary plug design inside and out
- Designed for use on high performance vehicles that utilize high output ignition systems
- Machined electrode increases exposure to the flame to improve combustion
- MSD’s proprietary ceramic formula provides the highest dielectric strength
- Yttrium ground electrode reduces the chance of pre-ignition
- Iridium tip improves cold starts
- All spark plugs tested prior to packaging and shipping
- Unique insulator design improves spark isolation
- Lower voltage Requirements for longer coil life
Specs
| Brand | MSD |
|---|---|
| Emission Code | 1 |
| Heat Range | 5 |
| Hex Size | 5/8 |
| Length | Standard |
| Plug Style Code | 1IR5L |
| Product Type | Spark Plug |
| Projected Tip | Extended |
| Quantity | 1 |
| Reach | 0.6910 |
| Resistor | Yes |
| Seat Type | Tapered |
| Style | Iridium |
| Thread Size | 14mm |
| Part Number | 3712 |
Emissions
This part is legal for use on Emissions Controlled Vehicles when used in accordance with the manufacturers application guide because it has a California Air Resources Board Executive Order number or is a direct or consolidated replacement part.
The following vehicles are considered Emissions Controlled Vehicles:
- 1966 and newer U.S. manufactured California Certified vehicles
- 1968 and newer U.S. manufactured Federally Certified vehicles
- 1968 and newer Foreign manufactured vehicle
*Free Shipping & Handling only offered to the contiguous US on orders over $100.
Some parts are not legal for use in California or other states with similar regulations.