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Kooks Long Tube Headers Install

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hey all, my husband is being a champ and installing my long tube headers in my 2012 Boss. He’s having a lot of issues getting the nuts out to take the old headers off. He’s working on the passenger side now and is 1 but away from being able to remove that side. Any advice on how to remove the top forward bolt? Or any advice on how to tackle the drivers side too? It seems like there’s just not enough room to work. I would be out there helping but being 8 months pregnant, I’m doing what I can to help.
I'm assuming that he didn't drop the K member to do this job? I can't even imagine doing it without getting that thing out of the way. I know someone has done it but take it from's the only way to go. I did the entire job myself....including K member. I would highly recommend someone help with the K member but it's not difficult and will save him hours and hours of frustration. I'm no master mechanic so if I can do it I know he can. It sounds like more work but it's not. I also made the mistake of leaving the original studs in the heads instead of using the new bolts so if you think getting at the nuts is hard now try it with the Kooks installed and those long studs. You need a lot of different tools to get at each nut. Wish I could remember what I did for that top front. Good luck.
@BossBabe302 welcome to TMO. I’ve never installed headers in a Boss but as Doc mentioned lowering the K member is what many members do when installing headers. Good luck and congratulations on the new addition to your family.


Because racecar.
Arizona, USA
In addition to the "drop the K-Member" suggestions, a variety of 15mm stubby and regular-length ratcheting box-end wrenches (with flex ends) will make this job a lot easier. But generally, any way you do it, it will be a PITA and involve a lot of cut up hands (unless the engine is out of the car altogether).

Mad Hatter

Gotta go Faster
Santiago, Chile
Looks like having the BMR engine mounts does make the job easier... My guy had them in and out in a couple of hours... and they were the drivers side. Better him then me...
In case this comes up again and someone uses the search button, dropping the K-member for a Kooks header installation really saves time and it the only way to go. Once the K-member is out of the way, bolt access with a various assortment or flexheads, wrenches, universals and sockets is pretty easy.

Having said that, American Racing Headers are much easier to install even with the K-member in place. If you are doing this job at home without a lift, get the ARH's.

I've done ARH headers in tech (hot) and they weren't horrible, but you can make it even easier by finding some special fasteners with smaller heads. Just like the 3/8 header bolts of old , with the 7/16 heads, you can find some in 10 mm instead of the 14 or 15mm stock head bolts/nuts. I forget the thread size, but you get the idea.
The two bolts above the driver side mount can be a real PITA when the car is hot, you can't get a full twist on them, although it looks like the aftermarket mounts help.

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