Ford Mustang BBK Headers - How To Install '05-'07 Headers
BBK's New Headers Are An Important First Step To Better Breathing For The Three-Valve, 4.6L Mustang GT
From the January, 2007 issue of Mustang Monthly
All contributors: Miles Cook
BBK's new headers for '05-'07...
BBK's new headers for '05-'07 Mustang GTs come with all the usual related installation hardware such as bolts, collector studs, flat washers, lock washers, and nuts. New gaskets are also provided. Part number 1612 is the standard finish, while 16120 is a ceramic-coated finish. Installing headers on the current Mustang is considerably easier than the previous-generation SN-95 car due to the overall larger size of the S197 platform. There's simply more room to work. While it still takes a while to do the job (about 4-6 hours), the added workspace is a welcome change.
Now that we're well into the third year of production for the S197 Mustang, the aftermarket and legions of owners have had plenty of time to figure out that these cars respond quite well to bolt-on upgrades. Better, in fact, than probably any previous Mustang generation.
Not one to be left behind in the evolution of 4.6 Mustang development, BBK Performance Parts has been right there every step of the way. This is evident by the impressive results we achieved last year when installing a few BBK bolt-on bits on an '05 GT.
In a nutshell, BBK's throttle body, cold-air kit, and underdrive pulleys netted a 30hp gain over the car's baseline, and keep in mind that this was at the rear wheels, not at the flywheel. At the flywheel, call it nearly 50 hp. Not bad for a few hours work and about $1,000 in parts and installation labor-even less if you do the installation work yourself.
This time we're turning our attention to the exhaust side of engine breathing by installing BBK's new shorty headers for the three-valve, 4.6-powered Mustang GT. The results are a worthwhile step on the path to more bolt-on power.
Note that we only installed and tested the headers themselves. This includes the '06 GT test car's stock mufflers and H-pipe. Combine the headers with BBK's soon-to-be-released crossover pipe and the other above-mentioned items, and more than 300 hp at the wheels will easily be the result. It's a setup we look forward to doing, and we intend to pass on the results when a BBK test car is complete.
While having a hoist makes...
While having a hoist makes the job easier, it can be done with a pair of sturdy jackstands with the car lifted as high as the stands allow. In any case, you'll be switching from underhood to undercar several times throughout the job, depending on which offers easiest access to various fasteners. After disconnecting the battery, remove the top bolt of the steering shaft. For better access to this top bolt, slightly turn the front wheels so the bolt is facing directly up, which will make it easier to fit the socket over the bolt. The bottom bolt is accessed from underneath the car.
On both sides of the engine...
On both sides of the engine (passenger-side shown here), remove the nuts that hold the factory manifolds in place on the studs.
On the driver-side of the...
On the driver-side of the engine, remove the bolt that secures the oil-dipstick tube to the cylinder head. Pull the tube straight up to remove it from the engine.
Although it might be considered...
Although it might be considered optional, we strongly recommend taking the following steps because it makes installation considerably more straightforward. Jack up the engine, support it with a block of wood under the oil pan, and remove the motor mounts. This sounds more difficult than it is, mainly because there's so much more working room on these newer cars than on an SN-95 Mustang. From under the hood, begin motor-mount removal by removing the one bolt on each side that holds the motor-mount ear to the subframe. With direct access to these bolts, it takes only a few seconds to remove them.
From here, the work is mainly...
From here, the work is mainly underneath the car. The next step is to remove the H-pipe. Start by loosening the two nuts on each band clamp, but don't remove them completely.
Pry up the locking tabs with...
Pry up the locking tabs with a small screwdriver while sliding the clamps toward the rear of the car.
There are four oxygen sensors,...
There are four oxygen sensors, one of which screws into the driver-side manifold. Unplug all four of them. Since there isn't enough room to fit your hand into their cramped location, unplug the two in front with a pair of large tweezers, as shown here.
The H-pipe is then unbolted...
The H-pipe is then unbolted from the stock cast-iron exhaust manifolds.
With the oxygen sensors unplugged...
With the oxygen sensors unplugged and the H-pipe separated at the front and rear, its mounting tabs slide from their rubber mounts to remove the pipe.
With the H-pipe removed, there's...
With the H-pipe removed, there's some working room under the car. Continue removal of the steering shaft by taking out the bottom bolt.
With both bolts loosened,...
With both bolts loosened, the steering shaft comes right out. Be sure the wheels are turned straight so when the shaft is reinstalled, the steering wheel will be oriented correctly with the front wheels.
At this point, the engine...
At this point, the engine can be raised since the motor-mount bolts were removed in Step 4. At BBK's shop, we used screw-type support stands to raise the engine enough to slide a block of wood under the oil pan. The engine is lowered onto the wood, and the support stands are removed. Do not attempt to lift the engine by jacking under the oil pan. Instead, position the support stands under the pan rails (where the oil-pan bolts are screwed into the engine block), or use another piece of wood between the pan rail and a small floor jack if you're working with the car on jackstands.
Motor-mount removal is simple:...
Motor-mount removal is simple: Remove the four bolts that hold the ear to the side of the block.
With the bolts removed, the...
With the bolts removed, the motor-mount ear lifts out. The design and engineering of the new Mustang make it easier to work underneath the car. Also helpful is how well the BBK headers fit. With everything removed, they fit onto the engine with no problem.
Most of the nuts on the bottom...
Most of the nuts on the bottom side of the manifold are best accessed from under the car. If you haven't yet removed all the fasteners that are best accessed from under the hood, you might have to make one or two trips back and forth before the manifolds are ready to come out. We switched from under the hood to under the car and back again several times, but the job is easier on the new car because the strut towers are further away from the manifolds, and the car is generally bigger overall. With plenty of working room on the driver-side, the stock manifold drops right out once its eight nuts are removed.
Unbolt the starter to allow...
Unbolt the starter to allow the passenger-side manifold to come out. Remove three bolts and it drops right down from the bellhousing. It doesn't need to be disconnected electrically and totally removed. Once unbolted, there's enough room to remove the manifold with the starter out of the way.
As with the driver-side, the...
As with the driver-side, the passenger-side manifold comes right off once all the fasteners are removed.
Compare the stock passenger-side...
Compare the stock passenger-side manifold with the passenger-side BBK header, and it's clear the BBK piece will free up exhaust flow by a good margin. While not a totally equal-length design, the BBK header is obviously much more "equal length" in nature than the stock manifold. All the tubes on the BBK header are as equal in length as space permits, while the stock manifold isn't configured that way at all.
The oxygen sensor needs to...
The oxygen sensor needs to removed from the factory manifold and reinstalled on the driver-side BBK header.
The headers and new gaskets...
The headers and new gaskets fit in place of the stock manifolds. Although BBK supplies a complete set of header bolts, it may be easier to reuse some of the original stud-type hardware, however the header tubes won't allow the factory stud and nut to fit in some areas. Also, the stud hardware makes it easier to position the headers correctly because the studs help locate the headers. At that point, you can simply thread the nuts onto the studs, then start the header bolts in other locations once the header is in place.
There might be an instance...
There might be an instance where a stud needs to be removed to fit the header because it either didn't come off with its nut or it can't be turned by hand. It's not a problem: The factory studs are equipped with a hex head that allows them to be removed with the correct-size socket.
With the motor mount and starter...
With the motor mount and starter out of the way, the passenger-side header also installs directly into place. Once the headers are securely bolted to the engine, everything goes back together in reverse order. This includes reinstalling the starter, motor mounts, steering shaft, dipstick tube, and H-pipe.
Reinstall the H-pipe and plug...
Reinstall the H-pipe and plug the oxygen sensors back into place to complete the job.
On the Dyno
If you only look at the peak horsepower gain, shown in bold numbers, then sure, the headers only gained 4 hp at the wheels. But you'd be missing the large majority of what the headers really did for our '06 Mustang GT test car.
Study the dyno charts to discern the real benefits of the BBK headers: improvements in torque output. For example, look at the results at 3,000 rpm. The car in the baseline test made 265.6 lb-ft. With the headers, the figure jumped to 283.2, an improvement of 17.6 lb-ft.
Torque is what you feel on the street, and having more of it in the midrange is what's important for slipping through traffic and getting up freeway on-ramps. At various speeds, power output isn't too bad either. Again looking at 3,000 rpm, the baseline test result is 151.7 hp. With the headers in place, output jumped to 161.8 hp for a gain of more than 10 hp.
Additionally, recall that we're only testing the headers here. With BBK's crossover pipe in place, figure another 10 hp or so improvement across the board or well over 300 hp at the wheels on this car already equipped with a BBK throttle body and cold-air kit. Note too that the power and torque peaks with the headers were at slightly lower engine speeds, which makes the power all the more usable on the street. Furthermore, with the headers, the torque curve stayed over 300 lb-ft from 3,750 all the way to 5,000 rpm, another notable improvement over the baseline test.
|Baseline: '06 Mustang GT with |
BBK throttle body and cold-air kit
|RPM ||POWER ||TORQUE |
|2,250 ||114.0 ||266.2 |
|2,500 ||127.3 ||267.5 |
|2,750 ||139.3 ||266.1 |
|3,000 ||151.7 ||265.6 |
|3,250 ||166.0 ||268.2 |
|3,500 ||188.1 ||282.2 |
|3,750 ||207.7 ||290.9 |
|4,000 ||229.9 ||301.9 |
|4,250 ||246.5 ||304.7 |
|4,500 ||261.4 ||305.1 |
|4,750 ||271.2 ||299.8 |
|5,000 ||284.2 ||298.5 |
|5,250 ||292.2 ||292.3 |
|5,500 ||292.4 ||279.2 |
|5,750 ||292.0 ||266.7 |
|6,000 ||291.0 ||254.8 |
|BBK headers |
|RPM ||POWER ||TORQUE |
|2,250 ||118.3 ||276.0 |
|2,500 ||131.9 ||277.0 |
|2,750 ||148.0 ||282.8 |
|3,000 ||161.8 ||283.2 |
|3,250 ||175.5 ||283.6 |
|3,500 ||197.9 ||296.9 |
|3,750 ||214.7 ||300.7 |
|4,000 ||236.0 ||309.8 |
|4,250 ||255.6 ||315.8 |
|4,500 ||270.0 ||315.1 |
|4,750 ||279.9 ||309.5 |
|5,000 ||291.9 ||306.6 |
|5,250 ||296.4 ||296.5 |
|5,500 ||286.2 ||273.3 |
|5,750 ||286.8 ||262.0 |
|6,000 ||286.9 ||251.1 |