I decided that I wanted to install a header on my '95 F-150 with the 4.9L inline six. Headers exist for the engine, made by Clifford, Hooker, and Hedman. Hooker and Clifford sell for $400 or more, the Hedman can be had for $200. The Clifford header says it will work with 91 & up fuel injected engines, but I figured for half the money I could make the Hedman work. I ran into a few minor bumps along the way so I thought I would share my experience in hopes that it will help somebody.

For my header I selected the Hedman Model 89300. Hooker makes a header for this truck as well but at more than double the price, I couldn't justify it. The Hedman header has 1 5/8" primaries as opposed to 1 3/4" for the Hooker version. Bigger might have been better, but again for more than double the price I really don't think it would be worth it. Besides, these engines are not exactly known for their high RPM operation, I figure the smaller tube will help some with the low end torque. Clifford would have also been 1 5/8" primaries. Since Clifford is a pretty big name in I-6 performance, I figure they'll know what they are doing.

The very first "problem" with the Hedman header is that it has no provision for an O2 sensor. Technically the O2 doesn't have to be located in the header, it could be further down in the exhaust system, but I wanted to minimize the chances of leaks ahead of the sensor. Any leaks upstream of the sensor will yield an artificial lean reading that causes the computer to run rich to compensate. This hurts power and mileage. I decided to have an O2 bung welded into the #3 primary tube. The second "problem" was really just one of personal preferences. I didn't really like the ball / socket style collector adapter on the Hedman headers. I had the same shop who welded in the O2 bung cut these out and install a set of v-band flanges. Strictly speaking I didn't have to do this, but I figured if I was going to do it, I might as well do it the way I want to. After these modifications were done I had the header ceramic coated black. The ceramic coating should help reduce under hood temperatures as well as protect the header from rust for years to come. At this point the header is ready to install.

Because the truck is intended for off road, the catalytic converters went away with this project. As such, I also elected to remove the AIR pump and EGR plumbing. AIR serves no purpose without a catalytic converter, and although I technically could have made the EGR work, I figured it really wasn't worth the hassle. Now because Ford thought it would be a good idea to plumb the AIR injection directly into the cylinder head instead of the exhaust manifold, I was left with 6 holes I needed to plug. There are many ways to do this. Some people just get bolts and thread them into the holes. I elected to use 1/4" NPT allen head pipe plugs. A word of caution here, you want steel or iron plugs. Brass is too soft and will strip out when you try to tighten it.

With the header ready and the AIR passages blocked off it was time to start with the re-assembly. The header fit just fine, but when I went to install the lower intake, the support braces between some of the intake runners contacted the header. The intake appeared fairly solid, with no real opportunity to flex anyway so I just cut out the support braces. Technically I didn't have to cut them all out, but I did anyway, mainly because we got carried away with the Sawzall. After that, the intake and header bolted up just fine. The header flange actually covered a few of the bolt holes so I ended up with some extra bolts. Looking at the thickness of the flanges and the factory mounting, I don't think this will really cause any trouble.

With the header and lower intake installed I was able to re-install the upper intake. This was fairly non eventful. I left the actual EGR valve bolted to the intake, however, there is a block off plate between it and the intake. In this manner the computer should be able to command EGR and "see" that the valve opens, it just doesn't really do anything.

The next problem came when I went to install the alternator bracket. The bracket contacted the #1 primary tube of the header. At first I thought I might could just notch the bracket but I saw that if I did that the header would simply touch the alternator. Since I didn't think taking a chunk out of the alternator would work so well, I decided to simply space the bracket over from the block a little bit. If the AIR pump was still installed, it would hit the frame, but without it this is no problem.

With the alternator spaced over and the AIR pump removed, I needed a custom sized belt. 96 5/8" worked for me, but if space the alternator differently than I did you may need a different size. I could probably get by with just 96" but I was able to get 96 5/8" and it worked so it's good for now.

To clean everything up I just capped any unused vacuum ports and left all the sensors and solenoids for EGR and AIR connected. This way the OBDI computer will "see" all the proper things and will command them to do what they need to do, they just won't do anything. According to information on this forum, that should be all that is needed to prevent a check engine light.

Ok, now that you're bored, let's go to the pictures.

Here is what it looks like from the top with the AIR rail and engine hoist bracket removed.


Here you can see the supports removed for header clearance.


Here you can see the oxygen sensor


Here you can see where the header would have contacted the alternator bracket.


Here you can see the alternator bracket spacers


Here you can see how the belt goes without the AIR pump


Here you can see the black header just kinda disappears


Here you can see the header collector with vband flanges installed. You can also see that I won't lose any ground clearance


And finally here you can see, looking back up from the bottom, that the header clears everything pretty well.


Results:
The truck starts, idles, and drives. Currently I don't have the headers connected to any kind of muffler so it's extremely loud, too loud to drive comfortably. I have got an intermittent check engine light which seems to be code 31. This indicates a possible poor electrical connection to the EGR solenoid. I have shot both sides of it with contact cleaner which should help. I'll play with it more once I get the exhaust connected and it's not so painfully loud.

There ya go, hope it helps. Please let me know if you've got any questions about how / why I did anything the way I did.

 

Here is an updated picture from underneath with the exhaust bolted up.



The truck seems to run great although I am having what I believe to be a heat soak issue with my starter.

I am still getting an intermittent CEL at idle that goes away the instant I hit the throttle. I ran out of time to mess with it this morning but I believe the problem is still with the EGR. I think with no pipe connected to the exhaust side of the EGR valve it is allowing the sensor to read out of range at idle. There should be any number of relatively easy ways to resolve this.

 

hey sorry to bother you since this is older post what size spacer did u use and length of bolts you used thank you