Harley Davidson Twin Cam engines are known for their performance, but they need the right parts to keep running smoothly. Spark plugs are crucial; they ignite the fuel mixture and keep your engine firing on all cylinders. Choosing the right spark plugs can boost your bike’s performance, improve fuel efficiency, and ensure reliable starts. I’ve spent years riding and wrenching on Harleys, so I know how important it is to get this right. Let’s look at some of the best spark plugs for your Twin Cam engine.
Product Overview
Here’s a quick rundown of the spark plugs we’ll be looking at:
- NGK DCPR7E Spark Plug: A reliable, all-around plug known for its consistent performance.
- Screamin’ Eagle Performance Spark Plugs: Designed for high-performance engines, offering improved ignition.
- Autolite 4164 Spark Plug: A budget-friendly option that provides good performance for everyday riding.
- E3 Spark Plug E3.31: Features a unique diamond-shaped electrode for enhanced flame kernel growth.
- Champion Copper Plus 710 Spark Plug: A classic choice, delivering reliable ignition and durability.
Top 5 Best Spark Plugs For Harley Davidson Twin Cam Reviews
1. NGK DCPR7E Spark Plug
The NGK DCPR7E is a standard, dependable spark plug that works well in a variety of conditions. It’s a popular choice for Harley Twin Cam engines because of its consistent performance and durability. It’s a solid all-around plug. I’ve used these in several bikes and never had an issue.
Pros:
- ✅ Consistent and reliable performance
- ✅ Durable construction
- ✅ Widely available and affordable
Cons:
- ❌ Not specifically designed for high-performance engines
- ❌ May not offer the same performance gains as premium plugs
- ❌ Some riders might prefer a more specialized plug
Verdict: Great for everyday riding and a reliable choice for most Twin Cam engines. If you need a dependable plug that won’t break the bank, this is a good option.
2. Screamin’ Eagle Performance Spark Plugs
Screamin’ Eagle Performance Spark Plugs are designed for Harley-Davidson engines that demand more power. These plugs provide enhanced ignition and are built to withstand the higher demands of modified or high-performance engines. They’re a bit pricier, but you get what you pay for. I noticed a slight improvement in throttle response when I switched to these.
Pros:
- ✅ Improved ignition performance
- ✅ Designed for high-performance engines
- ✅ Helps optimize engine output
Cons:
- ❌ More expensive than standard plugs
- ❌ May not be necessary for stock engines
- ❌ Performance gains might be minimal for some riders
Verdict: Ideal for riders with modified engines or those looking to maximize performance. If you’ve upgraded your engine, these plugs can help you get the most out of your investment.
3. Autolite 4164 Spark Plug
The Autolite 4164 is a budget-friendly spark plug that delivers decent performance for everyday riding. It’s a good option if you’re looking for a reliable plug without spending too much. I’ve used these as a temporary replacement and was surprised by how well they performed for the price.
Pros:
- ✅ Affordable price point
- ✅ Good performance for everyday riding
- ✅ Easy to find at most auto parts stores
Cons:
- ❌ May not last as long as premium plugs
- ❌ Not designed for high-performance applications
- ❌ Performance might degrade faster over time
Verdict: A solid choice for riders on a budget who need a dependable plug for regular use. Don’t expect top-tier performance, but it’s a great value.
4. E3 Spark Plug E3.31
The E3 Spark Plug E3.31 stands out with its unique diamond-shaped electrode. This design is intended to create a more efficient spark and promote better flame kernel growth. Some riders swear by these, claiming improved fuel efficiency and throttle response. I tried these once and felt a slight difference, but your mileage may vary.
Pros:
- ✅ Unique electrode design for enhanced spark
- ✅ Potential for improved fuel efficiency
- ✅ May offer better throttle response
Cons:
- ❌ Can be more expensive than traditional plugs
- ❌ Performance benefits may not be noticeable for all riders
- ❌ Some users report inconsistent results
Verdict: Worth considering if you’re looking for a spark plug with innovative technology. It might improve your engine’s performance, but results can vary.
5. Champion Copper Plus 710 Spark Plug
The Champion Copper Plus 710 is a classic spark plug known for its reliable ignition and durability. It’s a tried-and-true option that has been used in various engines for years. These are a staple in many garages, and for good reason. They’re simple, effective, and last a good amount of time.
Pros:
- ✅ Reliable ignition
- ✅ Durable construction
- ✅ Affordable and widely available
Cons:
- ❌ Not designed for high-performance engines
- ❌ Copper plugs may require more frequent replacement
- ❌ Lacks advanced features of newer plug designs
Verdict: A dependable and affordable choice for riders who want a simple, reliable spark plug. It’s a good option for stock engines and everyday riding.
Buying Guide
Choosing the right spark plugs for your Harley Davidson Twin Cam involves considering a few key factors. Here’s what you need to keep in mind:
- Engine Type: Are you running a stock engine or have you made modifications? High-performance engines often benefit from specialized spark plugs like the Screamin’ Eagle.
- Riding Style: If you mostly do casual riding, a standard plug like the NGK DCPR7E or Autolite 4164 might be sufficient. For more aggressive riding, consider performance-oriented plugs.
- Heat Range: The heat range of a spark plug is crucial. Using the wrong heat range can lead to engine damage. Refer to your Harley Davidson service manual for the recommended heat range for your specific Twin Cam engine.
- Spark Plug Material: Spark plugs come in various materials, including copper, platinum, and iridium. Copper plugs are affordable and offer good conductivity but wear out faster. Platinum and iridium plugs are more durable and provide consistent performance over a longer lifespan.
- Budget: Spark plug prices can vary significantly. Determine your budget and choose a plug that offers the best value for your needs.
- Thread Size and Reach: Ensure the spark plugs you choose have the correct thread size and reach for your Harley Davidson Twin Cam engine. Using the wrong size can damage the cylinder head.
FAQs
Q: How often should I replace my spark plugs?
A: Generally, it’s recommended to replace your spark plugs every 10,000 to 20,000 miles, or as specified in your Harley Davidson service manual. However, check them regularly for wear and tear. If you notice any issues like misfires or rough idling, it might be time for a replacement.
Q: Can I use automotive spark plugs in my Harley?
A: It’s generally not recommended to use standard automotive spark plugs in your Harley Davidson. Harley engines often require specific spark plugs with the correct thread size, reach, and heat range. Using the wrong spark plugs can lead to poor performance or engine damage.
Q: What are the signs of bad spark plugs?
A: Signs of bad spark plugs include: difficulty starting, rough idling, misfires, reduced fuel efficiency, and decreased acceleration. If you experience any of these symptoms, inspect your spark plugs and replace them if necessary.
Q: Will changing spark plugs improve my bike’s performance?
A: Yes, if your old spark plugs are worn or damaged, replacing them with new ones can improve your bike’s performance. You may notice better starting, smoother idling, improved fuel efficiency, and increased acceleration. However, the performance gains will be more noticeable if you upgrade to high-performance spark plugs.
Conclusion
Finding the best spark plugs for your Harley Davidson Twin Cam doesn’t have to be a headache. Whether you’re looking for a reliable, budget-friendly option or a high-performance upgrade, there’s a spark plug out there for you. Consider your riding style, engine modifications, and budget to make the right choice. Happy riding!
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