What Is The Spark Plug Gap For Chevy 350? (Explained!)

Knowing the gap of your spark plugs for your chevy 350 is very important. If you are interested to know what the gap of the spark plug is for a chevy 350. This article is meant for you.

So what is the spark plug gap for a chevy 350? The gap of the spark plug that will be used in chevy 350 is 0.035 inches. You can get any spark plugs for your chevy 350 in the auto parts store.

In the 1967 chevy Camaro, its high-performance v-8 option is the 350 small block engine. The 350 small block engine appeared first in a 1967 chevy Camaro. A year goes by, and it can already be asking for a chevy nova. 

A year after and you can already ask for a 350 engine in a Chevy vehicle. When talking about spark plugs, it is an essential part of your engine. You can locate the spark plugs on your chevy 350 in the sides of your engine. 

It is just on the outside of your cylinder heads. It is about eight spark plugs that are needed for the engine to operate and run smoothly. There are a lot of models, and each model has a different year of its engine. 

And it depends on the year of the engine that some spark plugs are sticking out. Sometimes, they are at a thirty-five (35) degree angle, and there is still the talk about the gap of the spark plugs. Now, we will talk all about the spark plug gap for a Chevy 350. Let us start. 

What Is The Spark Plug Gap For Chevy 350

What Should The Spark Plug Gap Be For A Chevy 350?

If you are looking for a spark plug for your chevy 350, you can buy them at any auto parts store. They are just readily available. However, if you buy spark plugs for your chevy 350, you should know that these spark plugs are already pre-gapped. 

They are gaped already after buying them in the store. However, you must always check if the gap is correct and suitable for your vehicle. 

You can check the gap in your spark plug by using a spark plug gap tool. So the gap for the spark plug of a chevy 350 small block is 0.035 inches.

What Is The Spark Plug Gap For Chevy 350 With HEI?

The gap for each spark plug in every vehicle will depend mainly on the ignition system. The performance orientation of the engine is also another determining factor. For example, a chevy 350 with a points style ignition must have a spark plug with a gap of 0.035 inches. 

However, for a chevy 350 with HEI, your spark plug must have a gap of 0.045 inches up into 0.60 inches. But, it would greatly help if you remembered that there is no one answer for all of this. 

Every distributor and every manufacturer will all have their recommendations and preferences. Therefore, they will be able to give different recommendations and preferences regarding the gap of the spark plugs in their every product.

What Spark Plug Gap For Chevy 350 With MSD?

For a chevy 350 that has MSD, the gap of the spark plugs must be 0.040 inches. But, again, every spark plug brought in the auto parts store is already pre-gapped. So you always need to check and verify by yourself if the gap is okay. 

You can use a spark plug gap tool. If you are also replacing your spark plugs in your chevy 350 with MSD, you should always be sure that the plugs have the correct gap. The gap is critical.

What Is The Gap Setting For Spark Plugs?

Gap setting is essential you should know as a driver. Every spark plugs you can buy in the market are pre-gapped. So for beginners, they might assume that the gap is already correct. 

But it is critical to always double-check the gap of the spark plugs you just bought. The gap of your spark plugs must be set correctly. You can find the correct gap in your owner’s manual. 

Every vehicle has its recommendation when it comes to the gap setting of the spark plugs. The gap setting of every vehicle is different. Every vehicle has its unique gap setting. 

Most of them would range between 0.028 to 0.060 inches. Again, consult your owner’s manual for the correct gap. So if you know more about the gap setting, you can do these steps. 

Find where your gap gauge is, or you can try finding your feeler gauge. After, clean your spark plug. If you have bought a brand new spark plug, you do not have to clean it. 

But if the spark plug is coming from your vehicle and it is not new, you might have to clean your spark plug. In cleaning your spark plug, be careful not to use a rough and abrasive material. Instead, use a soft and clean material. 

You then have to measure the existing gap of your spark plug. Run the gap gauge or the feeler gauge into the electrodes and know the measurement. Remember the measurement and then compare it to your recommended setting listed in the owner’s manual. 

If there are discrepancies, you have to make adjustments. In your gap gauge or feeler gauge, pick the correct measurement. 

Then, by using the spark plug gap tool, adjust your gap. Finally, recheck the gap, and make sure that it is already suitable.

Does The Spark Plug Gap Affect Performance?

The spark plug is made initially with a gap. The gap is in between the ground electrode and the center electrode. Therefore, one of the essential things in sparking is the gap of the spark plugs. 

The gap of the spark plugs will affect the performance of your vehicle’s engine. Therefore, the gap of the spark plugs must be fitted correctly so that your vehicle will have the best optimum performance. 

If your spark plugs have a narrow gap, it will then lead to a weak spark. As a result, it will not ignite your fuel or air mixture effectively.


In summary, the spark plug is an essential component in your vehicle. Another thing that is also important in the spark plugs is their gap. The spark plug gap must be correct in every way. 

It will determine the performance of the vehicle. For example, if the spark plug is wrongly gapped, your vehicle will not have the best performance.

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My name is Hank, and I've been in the automotive industry for 27 years. I've been working in my own auto repair shop for the last 13 years, and now I want to help you here, on my blog. Let me know if you have any questions. Read more