How to Install Headers on a 350?

If you own a 350 engine, you know how important it is to keep it in good condition. And one of the best ways to do that is to upgrade the headers. But installing headers on your engine can be intimidating, especially if you’ve never done it before.

In this article, we’re going to help demystify the process. We’ll go step-by-step through how to install headers on a 350 engine, from gathering the materials and tools you need to diagnose any issues that may arise during installation. So let’s get started!

How to Install Headers on a 350?

There is a certain method of installing headers. You have to know all about it if you want to do it yourself.

There are many parts of it like engine bays, bolt holes, stock manifolds, rear bolts, header flange, primary tubes, and lots more. You must know all of it first before starting the process. Check out the method step by step to get a better idea.

Step 1: Preparation

Whenever you are going to do something, you need to prepare for it. That’s the reason you do this installation after doing all the preparation first.

To do the method, first, you should do a plan of what you are going to do step by step. Also, take all the equipment beside you before starting the process. It helps you to do the process easily. So, make sure you arrange all the equipment first.

Step 2: Unpacking New Headers

After arranging all the equipment for your vehicle, now you need to do some unpacking. For doing that, first, unpack the new headers that you want to install. Get all the parts out of the package and bring all these things beside you.

That’s how it will be easy to get the necessary equipment when you need it. Also, get all the hardware arranged so that any necessary tools are available when you are going to start the process.

Step 3: Disconnecting Negative Battery Terminal

When you are doing header installation, make sure you disconnect all the negative battery terminals. It helps to avoid any electrical charge that occurs in several ways.

It appears around your engine block. If you don’t disconnect this negative battery terminal, it might get some electrical charge which is dangerous for you if you are doing the installation.

So, make sure you do that. Moreover, unplug the electrical oxygen sensors for safety. Remove the air box too if needed.

Step 4: Unbolting Exhaust Mid-pipe

Now, you should unbolt the exhaust mid-pipe that exists in the stock manifold. Go underneath your car and then do the unbolting.

Make sure you fully remove the mid-pipe to ensure ease of installation and a better outcome. Also, if you want to get any access to install the new header, you should unbolt it first.

Step 5: Disconnect All Hardware Equipment

After unbolting, now you should disconnect all hardware equipment to have more safety. The main reason for doing that, it prevents you from not accessing your manifold. So, it will be tough to do this method if the hardware is attached.

Besides, you also need to remove the spark plugs for better service. You can put any alternative to adjust the place. On the other side, you must remember where the connection starts and where to connect it again.

Step 6: Remove Manifold

Unbolt the manifold when you are starting the process. It helps to unbolt from both above and below the area. That’s why you can do the method easier and get a better service.

Besides, it can involve both the passenger and driver’s sides. That’s why you need to unbolt the places too. So, you should remove the manifold first. Also, check if the engine comes together or not. And if it happens, unbolt it from two points.

Step 7: Ensuring Perfect Placement

Now, it’s time to bolt the headers. Take the new set and start the process by checking if there is any adjustment needed or not. Go to the engine compartment with the equipment you need.

After that, take the header to install it in the right place. When all the arrangements are done, install your new exhaust header in the right place. Make sure you place the headers in a proper way where needed.

One thing you need to focus on is that the installation of cylinder heads will be from factory studs prior to fastening. This time, you have to attach the headers to the bolts as tight as possible.

Attach the headers in the exhaust system. The cylinders should match well. Also, the installation must be placed well. Check and make sure the lower bolts, middle bolts, and all the other bolts are tight enough. Factory exhaust should also be attached properly.

Step 8: Reattach & Re-install Everything

After completing all the installation processes, check if everything is attached well or not. And when you are done with your job, you need to focus on reattaching everything you disconnected.

Begin with reattaching all the parts, do the same with all the parts, and connect them as before. Place the things where they belong and carefully connect them.

Further, re-install header gaskets and mid-pipe too, and attach them to the back end of the manifold. Connect all header bolts well to the right places.

One thing is the main issue and that is the right place. When you are unbolting everything at the beginning of the process, you must remember the places where the parts belong.

Otherwise, when you bolt the parts again, it will be dangerous if you don’t bolt the parts in the right place. To secure the places, you have to maintain that.

Step 9: Connect Battery Terminal

The finishing process is to connect the battery terminal. For doing that, turn the engine on first and then connect the battery terminal.

Several other areas like header install and header collector are also included in this process. Also, the steering shaft and steering column need to be in place.

Listen to the sound of your engine and check if all the fasteners and bolts are tightened properly or not. It lets you know about your security.

How much horsepower do headers add to a 350?

If you use a usual 350, it can add 350 – 375 HP until you exceed the reliable components. Besides, it can make 400- 475 HP for a big block with the same stock component.

And in this case, it can add up to 500 HP until you exceed the stock cast pistons’ reliability.

What are the best headers for a 350-small block?

If you want a suitable header for a 350 block, then you need to choose accordingly. In this case, you need a header that has a 1 1/2” to 1 5/8” diameter.

Wrap Up

We have tried to give you some detailed information on the header installation method. You can learn a lot by reading this article.

All you should know is how to install headers on a 350 and what the quickest and easiest way of doing it is. Learn all the facts by checking the process that is described step by step.