Our rock-steady '03 Cobra...
Our rock-steady '03 Cobra has been pounding out the e.t.'s thanks to some sticky Nitto DRs and newfound power from a ported Eaton blower. Our new best is an 11.59 at 122 mph.
The magical numbers that pour out of Ford's latest supercharged mod motors make us look back and cry at the good ol' days of 5.0 racing. Looking back, you needed not one, but more often, two power adders to make anything over 450 hp at the wheels. Street racers, and even the big guns of Mustang racing used the hot setup of the time, which was to slap on a Vortech supercharger and a 100-shot of nitrous to dip into the 9s. Meanwhile, the most radical of EFI Mustangs sported big-dollar engine combos to get into the 8s, but often that resulted in unstreetable and often unreliable combos.
Fast-forward to 2009 and the early days of horsepower discovery are nothing but a long-distance memory, like cheese grater taillights, a short-belt, Pro-M 77mm mass air meters, and Reef Blue Metallic paint.
So when we say it's easy to make horsepower these days, we mean it. For instance, we've been able to witness this '03 Cobra make over 450 to the tires with nothing more than basic bolt-ons. As a matter of fact, this particular Terminator has already cranked out 453 rwhp and 453 rwtq with nothing more than a few normal bolt-ons, including a simple cold-air system, a cat-back exhaust, an overdriven supercharger pulley, and a quick reflash of the PCM.
Just 15 years ago, we would have given an arm, a leg, and maybe even a reproductive organ to make that much power. But when you can have it in a car that drives like it did when new, starts up every time to take you to work, and gets respectable fuel economy, it makes you happy enough to hug your local gas station attendant.
Even at $4 per gallon for hi-test, I can't think of any Mustang owner who's not looking to find a way to make their ride quicker. Aside from bragging rights at the parking lot of the local Choke `n' Puke (or Internet website), we all want to be slammed back into that seat and hang onto the steering wheel for dear life. We want to be scared and have things happen so fast that we barely have enough time to think. So, as addicted as we are to power, we decided to take a look at doing the normal thing that Cobra owners do next, which is to add boost.
After conferring with Mustang Magic's in-house tuner Joe Lauzardo and proprietor Joe Panciarello, we decided to install a ported supercharger. At our stage of the game, we were maxing out what the factory Eaton M112 can provide.
Even at 12 psi, the stock supercharger is limited by its outlet port size, which is a V-shaped opening that faces downward and dumps pressurized air into the intercooler core and the intake manifold. Total airflow and volume coming out of the stock blower is just about at its limit at 453 rwhp, so going to a ported unit would not only increase airflow and volume, but velocity as well, enabling us to increase boost pressures and ultimately, horsepower and torque. As luck would have it, a good friend of ours was upgrading to an aftermarket blower and we bought this ported unit, which was just sitting on his shelf, never used. He forgot who he bought it from but it looks like a rather professional port job. We figured there was no better way to see how it works than to dyno and drag test it.
With the blower in hand, we called Mustang Magic, where Lauzardo explains, "On a car like this, a ported blower will usually not give you tons of peak power, but rather big gains in torque, especially when driving around town. To make it work, you should put on more aggressive pulleys to get the blower spinning faster so that the power comes in early and it snaps when you hit the gas pedal. You should use a four pound pulley on the crank and leave the 3.0 upper pulley that's on there."
Finding a company that sells...
Finding a company that sells a ported Eaton supercharger is not as hard as it used to be in 2003. For our test Cobra, we picked one up that was sitting in our friend's garage but its origins are unknown. Although it looks like a stocker from the outside, it's what's inside that counts.
Looking into the inlet side...
Looking into the inlet side of the ported unit, we can see how the passages have been matched to the flange gasket and how the entire area has been smoothed for greater airflow. Anytime you remove restrictions from the inlet side of a blower, power and efficiency always go up.
First order of business underhood...
First order of business underhood is to remove the emissions control devices from the side of the supercharger housing. We find it easiest to remove it as an assembly, with the bracket, solenoids, and signal hoses as a unit. Be mindful not to damage any of the tubes, however.
First up, we checked the fluid...
First up, we checked the fluid level in the front drive section of the supercharger. With the plug removed and the supercharger sitting level like it was in the car, the fluid should sit right at the level of the fill hole. Luckily, ours was full of fresh lube, but if yours isn't ask your local Ford dealer where to get some.
With the four nuts removed...
With the four nuts removed from the intake plenum's flange, undo the throttle linkage and wiring to remove the entire throttle body assembly.
Using a large adjustable wrench,...
Using a large adjustable wrench, undo the large pipe fitting for the EGR feed tube and then unbolt the EGR valve itself with a 10mm wrench.
At the front end of things,...
At the front end of things, remove the supercharger drive belt and the front pulley assembly to gain access to the intercooler coolant manifold. Then drain the intercooler system by removing one of the intercooler pipes underneath and remove this manifold while watching the two pipe extensions that are behind it.
Side by side, you can see...
Side by side, you can see how the ported outlet of the unit that we are about to install on the right offers significant increases in total airflow, but with a potential loss in velocity. Nevertheless, the potential for more power is found right here.
Transferring the intercooler...
Transferring the intercooler core is a delicate job, so when removing the ten bolts, be careful not to snap them as they are held in with thread locking compound from the factory. We strongly recommend using thread-locking compound when installing the bolts because if a bolt comes loose, it will go right into your engine and spell disaster.