Header Exhaust Wrapping

Published on
June 10, 2024 at 8:06:50 AM PDT June 10, 2024 at 8:06:50 AM PDTth, June 10, 2024 at 8:06:50 AM PDT

We have wrapped many headers and other exhaust components in the shop and wanted to share with you what we feel are some of the best practices and techniques we have gained through experience.

For this installation we are wrapping a Subaru STI manifold and upipe with Heatshield's Inferno Wrap.

Before you begin wrapping your header you may want to gather a few very basic tools to help make the job as easy as possible. I'd recommend grabbing the following:

  1. Bucket
  2. Safety Glasses, Dust Mask, & Gloves
  3. Long Sleeves
  4. Thermal Ties, Stainless Steel Wire, or Hose Clamps
  5. Side Cutters and/or Wire Twisting Pliers
  6. Sharp Heavy Duty Scissors or Tin Snips

Step 1:

Put on your safety gear and remove the wrap from the packaging and submerge it in water in a bucket. By soaking the wrap you will help minimize the amount of fiberglass fibers. Just as an FYI, Heatshield does not recommend soaking their Colored Wraps. However, all of their other wrap products can be soaked.

You may need to loosen the spool of wrap in order to have it saturate thoroughly. Don't worry if it comes unraveled, you will most likely find yourself unraveling it anyway to make installation easier. You'll probably find the wrap needs to soak for 15-20 minutes to become thoroughly saturated.

Step 2:

While your wrap is soaking, grab the parts you are going to be working with as well as the remaining tools you need. At this point, we have found securing the parts to a workbench definitely helps to make the wrapping process easier and the end result cleaner looking in appearance. Securing the part will allow you some leverage to pull the wrap as tight as possible, without having to fight against a part that is moving around. You'll have to decide what securing method will work best for you, in our shop we have holes drilled through a metal fab table so we can bolt the header flange directly to the table surface. Using a few c-clamps or vise clamps would probably get the job done also.

Step 3:

Once your part is secured, pull the wrap out of the water. You may choose to work with the wrap as one continuous strand, or if you have calculated how much wrap you will need for various sections now would be the time to cut the wrap into the lengths needed. One word of caution if you pre-cut your wrap. Always hedge on the side of caution so you don't come up short. If you think you need 10 feet, you may want to cut yourself a 15 foot piece of wrap to work with so you have some "play" room.

Now that you are ready to begin, you'll want to start the wrapping at the point of the part closest to the motor. We generally also choose the runner or primary that we think will be the most difficult to reach to start with. Our reason for this is as you begin the wrapping process, small spaces only get smaller, so by starting with the hardest to reach runner or area, you will save yourself and your fingers some frustration down the road.

Begin by folding the end of the wrap over on itself. This will help prevent the edge from fraying. Next, make your first wrap. Once you see how your first wrap is going to fit we suggest running a piece of wire through the middle of the wrap and securing it in position. Note that this single tie will not be enough to keep the wrap from spinning as you try and pull it snug, you will need to make a few additional wraps before you reach that point. By securing the wrap like this you are keeping the first wrap against the flange and also making sure the piece that is folded on itself stays put and doesn't somehow come undone. (See photo below)

Step 4:

Continue wrapping the runner using a 1/4" overlap with each pass, being sure to pull each wrap as tight as you can. Secure it with Thermal Ties, wire or hose clamps as you go. Once you have finished the first runner we recommend going back to finalize any securing it may need. We always pay extra attention to the ends, since if the wrap is going to work itself loose chances are that's where it would start. Having the wrap secured every 4 inches or so will be more than sufficient.

Step 5:

Continue the same process for each additional runner/primary. If you reach a point where the runners are too close together to wrap individually you can wrap them together. Once you are finished wrapping the component, double check that you have the wrap adequately secured.

Step 6:

At this point we hang our pieces to dry overnight. If you are in a rush you can set a fan up in front of them to help expedite the drying process. Once the pieces are dry you can reinstall them on your vehicle.

Step 7:

After your wrapped parts are installed they will need to cure. Park your vehicle outside and let it idle for awhile. You'll notice the wrapped components smoking, and you will smell the fiberglass. This is normal, and it will stop once the wrap is cured. Once the smoking seems to have subsided you can take your vehicle out for a ride. You may still see some smoke if you are stopped at a light, but after the wrap heat cycles a few times this will stop.

That's about all there is to it. This is not a difficult job, so don't be afraid to tackle it. The most important thing is patience. You want to make sure you take your time, and install the wrap as snug as possible.