I have installed a few different types of headers and there are two brands that stand out for quality and fitment.The GT Spec Header and Perrin both stand out above the rest. Here are some photos and information regarding a pair of GT Spec headers on a WRX.
GT Spec made a beautiful header and up pipe combination. The welds look great, the gauge of the steel feels strong, the collectors are formed well, the 3 bolt flange for the up pipe while being difficult to bolt down should keep it from leaking. My only complaint and I’m hoping it just didn’t make it into the package is they do not include studs to bolt the up pipe to the turbo. We had some issues removing stock studs so we made it to Subaru minutes before closing only to find out, they don’t actually sell up pipe studs. We had to get the studs which mount the headers to the exhaust manifold. Not ideal, but it did get us through the install. If you decide to go with this well made setup, you might first get some studs from here.
Installing the headers proved to be a little tricky. Even with loosening the expansion joint, only 5 of the six bolts would line up. We tried Darin at one side and myself at the other, still no go. A pry bar didn’t do much help either. I decided to put a little back into it as they say and borrowing from a jiu jitsu move I placed myself sideways under the headers, locked my elbows into my hips and thrust my 115 pound frame up and into the driver side header which created enough force it actually seated all the way onto the studs. And with that and a simple “yeah, who’s your daddy now, BITCH” it was mounted.
Now the next challenge was bolting the header to the up pipe. The location of 2 of the three bolts require a bit of patience to tighten down along with 2 14mm standard box end wrenches. As I’m writing this, I wish I would have taken a picture, but suffice to say it can be done.
Torque everything down, reinstall the down pipe, reinstall the heat shield, check to make sure everything is good. Start the car, listen for leaks, reinstall lower splash guard and take for a test run. Pauls initial reaction included exposed teeth and comments such as “I don’t even have to get on it to feel the difference.” I’ll be adding the GT Spec header and up pipe combo to my recommended list based on this install and his reactions.
Most of this install is straight forward, there are however a few things to watch out for.
1. The lower cross-member will need to be modified to clear the headers. When I first heard about this I was a little concerned; however, after seeing how much it’s really not a big deal. Basically, just tap a flat piece of the cross member in less than a quarter of an inch. I used a 2.5 pound hammer for this and with a couple of gentle taps it was done. Picture number 6 kind of shows this.
2. The 3 bolt flange is great for avoiding an up pipe leak between the exhaust manifold and the uppipe, however getting to those bolts is no easy task. Don’t let this discourage you though as the end results are well worth it.
3. Get some studs before starting this and have them installed as reusing the stock studs does not always work out.
4. We had a bit of an issue with the spacing. 5 of the 6 exhaust manifold bolts were groovy… the last, not so much. I used a simple jui jitsu toss where an elbow lock and hip thrust was able to massage everything into place.
That pretty much covers it other than the standard exhaust manifold and up pipe install. If you have any questions feel free to ask in the comments.