Dr Jamie Meyer
May 1, 2004
Contributers: Brian Herron Of Apten Performance Photos By: Brian Herron Of Apten Performance

Horse Sense:
As with so many cottage businesses making a go of it on the Internet, we hadn't heard of Apten Performance until we saw message-board posts about its modified blower for '03 Cobras. We discovered that not only does the company offer products for Mustang Cobras, Bullitts, Mach 1s, and GTs, but it also addresses such niches as Thunderbirds, Explorers, Rangers, and Sport Tracs. Apten's modified stock blower makes power in an interesting way That's a jump of 36.4 rwhp and 9.6 rwtq with a supercharger swap that no one can detect

We're having a great time adding parts to the new king of all musclecars-the '03 SVT Mustang Cobra. This thing rocks from the second you fire it up, and it only gets better when you add a few hot-rod parts. So far we've given you the skinny on cold-air kits, performance exhaust systems, shifters, pulley swaps, computer chips, and a few other tips along the way. Just opening up the inlet and exhaust sides of the raucous factory-blown 4.6 four-cammer is enough to make your hair stand on its end. But when you add a supercharger pulley for more boost and then top it all off with a good tune, this sucker gets up and begs like only one or two percent of all performance cars ever built.

Along the way, our friends at Paul's Automotive Engineering have acted as hosts and judges of some of the best aftermarket companies in the country with their in-house chassis dyno and talented Ford performance technicians who have assisted us with installations and evaluations. This time around, we're going to dig a little deeper into that marvel of technological torque under the hood with the addition of a ported stock Eaton M-112 supercharger from Apten Performance, which we'll pair with a more efficient heat exchanger from AFCO Racing Products.

AFCO has been making heat exchangers for the SVT Lightning for several years, and as does much of the Cobra technology, this is an area that borrows from successful Lightning products. The factory system circulates an antifreeze mixture through the intercooler mounted under the Eaton supercharger and through the heat exchanger located in the front of the car. There is a reservoir located under the hood to allow owners to maintain the fluid levels in their intercooling systems. The AFCO unit ($429) replaces the stock heat exchanger behind the front bumper and increases surface area for heat exchange by more than 30 percent. And, we can't stress enough how simple it is to swap this unit into the car. You don't have to remove the bumper or any of the other factory gear. The AFCO unit bolted into our car in less than 10 minutes, and it worked like crazy to keep inlet temperatures down, especially in our heat-soaked, three-back-to-back-run test.

We first heard about Brian Herron's Apten Performance-modified stock Eaton supercharger on one of several different Web sites that cater to factory-blown SVT Cobras. The word was that Brian could take your stock blower and for a reasonable fee ($599) work it over to result in appreciable gains on the chassis dyno and-more importantly-the seat of your pants.

Our photos will detail what the difference is once Brian has worked his magic. For us, it is an awesome modification that we highly recommend. Perhaps the most important reason we like this modification is that no one knows it's there. There is a slight sound difference, but other than actually removing the blower, no one can tell you've tweaked the car. The results are well worth the coin and effort. We easily saw the advertised 30-plus horsepower increase at the tires, and the majority of that is across the entire rpm range. There is also a noted increase in torque.

Apten's modified stock blower makes power in an interesting way. In stark contrast to swapping the blower pulley (the most obvious and dramatic way to increase power on an '03-'04 SVT Cobra), there is no increase in boost. Instead, the Apten modifications make the supercharger more efficient by decreasing the amount of power it takes to turn the blower itself as well as decreasing inlet temperatures by more than 10 degrees. As you can see in our photos, the outlet side of the blower is modified in such a way as to open up a larger surface area of the blower to the stock intercooler, thus decreasing inlet charge temperatures. Again, boost and engine rpm will stay the same, but you will see a jump of 30-40 rwhp in the car across the powerband.

While we took advantage of Brian's skills with the Superchips Custom Tuning software that he knows so well, it is important to point out that you will not need to have the car retuned if you just swap on the Apten. This is because the efficiency of the engine-not the boost-is increased. Also, Brian pointed out that his blower, combined with a 2.8 pulley, a cold-air intake, an AFCO heat exchanger, and a good exhaust system, will put the average '03 Cobra over the 500rwhp mark and right at the point where a custom fuel system and retuned mass air should be considered. Of course, at this point you will have a 500-rwhp car that acts just as it did stock-until you drop the hammer.