Best spark plugs for 5.7 Hemi (Top 3)

If you have a 5.7 Hemi engine in your car, you need to use the best spark plugs for optimal performance. A bad spark plug can cause all kinds of problems with your engine, including decreased fuel economy, loss of power, and even engine damage. In this blog post, we’ll discuss what makes a good spark plug and some of the best options for 5.7 Hemi engines. We’ll also talk about how to choose the right plugs for your car and what to look out for when buying them.

Let’s take a look!

What do spark plugs do exactly?

Inside the engine of every car there is a spark plug, which has the important function of igniting the air/fuel mixture so that it can start the combustion process. This mixture is what powers your car, and without a spark plug your engine would not be able to run.

Spark plugs are made of a metal electrode surrounded by an insulator. The metal electrode conducts electricity from the ignition system to the air/fuel mixture. The insulator protects the electrode from being damaged by the heat of the combustion chamber.

Over time, spark plugs can become dirty or damaged, which is why they need to be replaced periodically.

Why good quality spark plugs are important

Using quality spark plugs is important for several reasons. First, good spark plugs will help your engine run more efficiently, which can lead to better fuel economy. Second, high quality spark plugs can help prevent engine damage by igniting the air/fuel mixture more consistently.

See also  Screamer Pipes Explained - What Are They?

Cheap or dirty spark plugs can cause misfires, which can lead to engine knock and decreased performance. In extreme cases, engine damage can occur if the problem is not resolved quickly enough.

What to look out for when choosing spark plugs for your car

Spark plugs are an important part of your engine that needs special care and attention. They can be replaced with copper, iridium, or platinum material with different properties depending on what you want – affordability versus longevity, etc., but make sure they match correctly first!

The following steps are a guide on how to select the best spark plugs for your car:

1. Choose the right type of plug

There are three main types of spark plugs: copper, iridium, and platinum. Each has its own pros and cons that you should consider.

2. Select the correct size

Spark plugs come in different sizes, so it’s important to choose the right size for your engine. The wrong size can cause damage to your engine.

3. Choose the correct heat range

Spark plugs have different heat ranges, which indicate how hot or cold they should be for optimal performance. If you live in a hot climate, you will need a warmer plug, while a colder climate requires a cooler plug.

4. Consider the brand.

Some brands of spark plugs are better than others. Do some research to find out which brands are best for your car.

5. Compare prices.

Spark plugs can vary greatly in price, so it’s important to compare prices before buying. You should also consider the quality of the plugs when comparing prices.

The 5.7 Hemi has 16 spark plugs on the engine.

best spark plugs for 5.7 Hemi

Why does the 5.7 Hemi use 2 plugs per cylinder?

Two sparks ignite the air-fuel mixture more evenly, generating more power for the power stroke

See also  What is a Transfer Case on a Vehicle?

What are some vehicles that use the 5.7 Hemi engine?

The 5.7 Hemi engine is used in a variety of vehicles including the Dodge Charger, Dodge Challenger, Jeep Grand Cherokee and Ram 1500.

If you own one of these vehicles, you need to make sure you are using the best spark plugs for this engine.

Best Spark Plugs for 5.7 Hemi Engines?

We’ve moved on and compiled a list of the best spark plugs you can buy for your 5.7 Hemi.


It’s always best to use OE, or original equipment, aftermarket parts when possible. This is because OE parts are designed specifically for your vehicle’s make and model. Replacement parts may not fit as well or function as well as original parts. In the case of spark plugs, using the wrong type of spark plug can result in engine damage. NGK LZFR5C-11 Spark plugs are OE replacement for the 5.7 Hemi engine. These plugs are designed specifically for this engine and will therefore provide the best fit and performance.

best spark plugs for 5.7 Hemi

  • Thread Size 14mm x 1.25mm
  • Reach 25 mm
  • heat range 5
  • Seat Type Gasket
  • Materials Copper/Nickel
  • Clearance 0.043″ (1.1 mm)

If you are looking for a high quality spark plug that will keep your 5.7 Hemi engine running strong, CHAMPION 446 is an excellent choice. These plugs are specifically designed to provide superior performance in Hemi engines and are backed by a long history of Champion brand excellence.

best spark plugs for 5.7 Hemi

  • Thread diameter 14mm
  • Thread pitch 1.25 mm
  • Joint Seat Type
  • Reach 26.5 mm (1.04″)
  • Hex size 5/8″ (16mm)
  • Solid Type Terminal
  • Clearance 039″ (1.0 mm)


The AUTOLITE APP5325 spark plug is a great choice for the 5.7 Hemi engine. Offers superior performance and durability, making it ideal for high-performance applications. Featuring a copper core electrode and a platinum tip, the AUTOLITE APP5325 offers reliable ignition and long life. It also provides excellent antifouling properties, helping to keep your engine running clean and smooth.

See also  My car shudders when slowing down - why?

best spark plugs for 5.7 Hemi

  • Thread size 14 mm X 1.25
  • Reach 3/4″
  • Hex size 5/8″ (16mm)
  • Joint Seat Type
  • Clearance 044″/1.1 mm
  • Iridium type metal
  • Solid Type Terminal

What is the correct gap for a Hemi 5.7 spark plug?

Recommended clearance for 5.7 HEMI is 0.039-0.044 inches or 1.0-1.1 mm

The correct spark plug gap is important because it ensures the spark plug fires correctly. If the gap is too large or too narrow, the spark plug may not work properly. This can lead to a loss of power and fuel efficiency and can even damage the engine.

Some spark plugs come pre-gapped, but most do not. You will need to check the spark plug gap and adjust it if necessary.

How often should you replace your Hemi spark plugs?

For optimal performance, it is recommended that you check your Hemi spark plugs every 30,000 miles. However, if you notice any loss of performance or fuel efficiency, it’s a good idea to check the plugs and replace them if necessary.

Replacing spark plugs is a relatively simple and inexpensive task that can make a big difference in your engine’s performance. If you are not sure how to replace your spark plugs, consult a professional mechanic.

How to Check the Spark Plugs in Your 5.7 Hemi

The spark plugs on your 5.7 Hemi engine need to be checked regularly to see if they need to be replaced. Here is a guide on how to do this:

1) Remove spark plug coil to access spark plugs.

2) Use a ratchet and socket to remove the spark plugs.

3) Inspect plugs for wear or damage. use a spark plug opening tool to check the gap of the plugs. If the clearance is not within the correct range, you will need to adjust it.

4) If the plugs are damaged or worn, replace them with new ones.

5) Reinstall spark plug coil and other parts removed.

6) Start the engine and check that it is working properly.

Go home

Leave a Comment