460 Header R&R

[Silverback51]

The passenger side is a breeze. Jack up the engine and it drops right out.

The driver’s side is another story.

Needless to say, you first need to remove the side pipes and then remove the fasteners securing the headers to the heads. Just let the headers drop down and rest where they may.

In order to jack the engine high enough, you need to remove the valve covers and disconnect the throttle linkage at both ends of the jack shaft.

I used a hydraulic floor jack with a 2X4 that spanned the oil pan in a crosswise direction. I also used a .5 thick shim on the driver’s side to kick the engine a little higher on that side for some additional clearance.

Next you need to remove the stainless heat shields along the foot box, wheel well, and under the brake booster. Then you can remove 7 of the 8 bolts that hold the pedal assembly to the foot box. I could not get to the most forward one between the inner fender and the pedal assembly so I just left it in place and was able to lift it high enough to make it work.

Now I removed the two brake lines from the master cylinder. Be sure to have a couple plugs handy so that you can plug the master cylinder and not have it leaking all the time you are working. Remove the clevis bolt from the brake pedal and the brake booster assembly. Then remove the 4 nuts holding the brake booster to the firewall. Remove the access cover from the wheel well, and then slide the brake booster forward and rotate approximately 90 degrees clock wise so the master cylinder reservoir is tilted towards the passenger side.

Remove the socket head cap screw that connects the u-joint to the steering shaft. Be sure to mark it in some way incase it slips out or rotates. Then remove the large bolt that connects the steering shaft to the pedal assembly.

I should mention that I removed the drivers seat to make it easier to access all of the fasteners that you have to get to in the pedal box area.

I then went under the car and rotated the header with the forward end going up and the aft down towards the opening. Still could not get it out, but it was close. I then put a cut off disk in my die grinder and cut off approximately 3/8 of an inch from the header flange that was resting on the frame. Be careful when doing this as the brake line is right behind it.

With that 3/8 of a inch removed, I was able to force the header up and then rotate it out.

To make the installation of the new header easier, I applied some machinist dye to the header flange and set the gasket on it. Scribed a line at each end at the bottom of the flange and then once again cut off approximately 3/8 of an inch. This allowed the installation of the new header with minimal frustration.

All together it took me close to 8 hours to do the header swaps. Now I tend to work slow, drink a beer or two, and think about things. Some could do it faster, some slower, but it can be done without removing the engine, which is what I originally thought it would take.

Hope that helps anyone that finds themselves in the same situation.