Heat shields for 4-into-4 headers - inexpensive how-to

[Gumball]

I've been concerned about radiant heat from the FFR-supplied 4-into-4 headers and wanted to do something to protect the things mounted above the headers (master cylinder, steering shaft "U" joint, brake lines, heater hoses, windscreen washer fluid reservoir), and the foot boxes from the high temps. My focus was on where the four pipes come together and run straight, rather than the upper portion of the headers (although there is obviously even more heat up near the heads).

After not really finding a good commercial solution, I decided to fab up something simple and thought I'd share this with you guys in case anyone is trying to solve the same problem.

Materials included:
- two pieces of .040 aluminum (11"x13" driver side and 11"x11" passenger side)
- 16 aluminum discs 1/2"x1" (could substitute eight 1/2" thick pieces of bar stock that is 3" long - four per shield)
- 16 long 1/8" rivets
- 4 large band clamps (McMaster)

Using my benchtop Harbor Freight bending brake, I bent the large pieces of aluminum 90" down the middle of the 11" side and then 45* 3/4" in from the end (on the 13" long sides on the driver's side shield).

In order to get the shields to stand off from the headers, I made 1/2" tall pedestals using some scrap aluminum round stock that I had laying around. I wanted to have one set on each pipe at the end of each side of the shield - i.e., 4 stand-offs per flat side of the shield. This required a total of eight stand-offs per shield, but you could simply replace those with a couple strips of aluminum bar stock for even easier fabrication. The goal here is to just get the shields to be held away solidly and uniformily on both sides.

To mount the stand-offs to the shield, I drilled each one through with a #30 bit, then countersunk one side about 3/8" so that the rivet would pull and fill the void.

To attach the shields to the headers, I used stainless steel band clamps from McMaster - they're the large size that goes from 4 1/8" to 7" - around $9 for a set of five. For these, I slotted the shields by drilling a pair of holes, then slicing out the area between the holes using a dremel with a cut-off wheel... just required a little filing to make the slots look decent.

I used scrap aluminum sheet and bar, so I don't have an actual price, but I'm guessing you could make a set of these for under $25 if you had to buy everything at the local hardware store.

Here are a few pictures of the finished product...

http://i845.photobucket.com/albums/ab15/CCRsAC/IMG_20140609_2056085431_zps9c61756a.jpg (http://s845.photobucket.com/user/CCRsAC/media/IMG_20140609_2056085431_zps9c61756a.jpg.html)

http://i845.photobucket.com/albums/ab15/CCRsAC/IMG_20140609_2100183821_zps47bd5971.jpg (http://s845.photobucket.com/user/CCRsAC/media/IMG_20140609_2100183821_zps47bd5971.jpg.html)

http://i845.photobucket.com/albums/ab15/CCRsAC/IMG_20140609_2055158901_zps17c92ed8.jpg (http://s845.photobucket.com/user/CCRsAC/media/IMG_20140609_2055158901_zps17c92ed8.jpg.html)

http://i845.photobucket.com/albums/ab15/CCRsAC/IMG_20140609_2123529601_zpse6a8709f.jpg (http://s845.photobucket.com/user/CCRsAC/media/IMG_20140609_2123529601_zpse6a8709f.jpg.html)

[DaleG]

Very nice solution; much cleaner than than my piece-meal use of header wrap for Earl's ducts and heat sleeve for wiring.

[skullandbones]

Hi Chris,

Nice work. Are you planning to measure the temperature changes that you see with the shrouds installed? It's funny because the ceramic headers are supposed to reduce the heat from the tubes (by trapping it inside) as it passes through to the side pipes. I haven't gotten a chance to measure mine against a friends non ceramic coated ones, yet. You aren't trying to reduce temp but to reduce the radiant energy in that critical area for the good of the plastic and rubber components, as I understand it. Will they get heat soaked at some point? Doesn't matter if they shield the critical parts. The heat dynamics in the engine compartment causes a lot of head scratching on my part. I hope they work as well as they look.

Let us know the results.

WEK.

[Gumball]

As the pics show, these leave the headers open at the front and bottom, hopefully to allow airflow around them and through the area between the pipes and the shields. I'm also considering a hole with screen in the splash guard - similar to some of the original race cars - as a means of increasing airflow in this area and out through the side vents.

I also did as Dale mentions and wrapped / insulated some of the critical parts... but for some components that's not an option so I thought that a simple block with airgap would suffice to reduce the radiant heat on those components. We'll see, though.

Here's a pic of an original car with the hole in the splashguard...

http://i845.photobucket.com/albums/ab15/CCRsAC/FrontWheelWellVents.jpg (http://s845.photobucket.com/user/CCRsAC/media/FrontWheelWellVents.jpg.html)

[skullandbones]

I was going to ask you about the elephant ears as I have not installed mine yet just for that reason. I should have known you would have a reference to it if it was done on the original cars. I didn't mention it because I thought I was getting to far away from the thread focus. So you did it. That's OK! I will have to consider doing that with the splash guards.

Thanks,

WEK.