Let's Face it, fun with 5.0 Mustangs never gets old, so when we get our hands on a stock Fox-body Mustang, we know we'll have a blast making it go fast. Last month, we installed a Nitrous Express nitrous-oxide system on a rather slow-moving '92 Mustang notchback ("It's Time for Nitrous," Feb. '07). Saddled with an AOD transmission and a few mods that included Ford Racing Performance Parts underdrive pulleys, 3.55 gears, and a Flowmaster off-road exhaust, the little Pony mustered only a 15.12 at 92 mph on motor. This is a common e.t. for a such-equipped vehicle. With the NX system hosing down the intake manifold with the icy nitrous/gas mixture, the black coupe charged to a 13.62 at 104 mph.
The Ford Racing Performance...
The Ford Racing Performance Parts 5.0 Cobra intake manifold, along with the venerable GT40 intake, have been staples of the 5.0 community for decades. Now you can get the Cobra intake with a polished finish, so you can look good at the car show and lay down the smack at the track.
Knowing that we could potentially be waxed by the latest Honda Accord or Nissan Altima without the bottle, we decided to bolster the notchback with a few bolt-on parts to up the naturally aspirated horsepower number. Since the coupe already had underdrive pulleys and Flowmaster mufflers, we opted to complete the exhaust system with an off-road x pipe system and 151/48-inch, equal-length, shorty-style headers from DynoMax. Part number 87704 netted us a pair of Cyclone ceramic-coated headers, while PN 88019 got us an aluminized x pipe system.
Short of a K&N filter in the stock airbox, the induction was stock, so we went big with our first mod in this area by ordering an FRPP Cobra intake manifold with a shiny polished finish (PN M-9424-Z51P). The Cobra manifold helped the '93 Cobra produce 235 hp from the factory and 305 in the FRPP performance package. Knowing that it was used on a production vehicle told us that installing it would be a no-brainer.
After disconnecting the battery,...
After disconnecting the battery, our man of action, George Xenos, pulled the rubber intake elbow, the distributor cap and plug wires, and the distributor. Before you pull the distributor, mark it and the block with a hash mark across both, and do the same for the bottom cap and rotor. This will get you close upon reassembly, but you'll still need to put a timing light on it and check the initial setting.
With a couple of buddies turning the wrenches, installation took less than a day, and the dyno results were impressive given the modest bolt-ons that were employed. Our baseline (prior to the intake install) produced on our in-house Mustang Dynamometer, came in at a measly 170 rwhp and a pathetic 209 lb-ft of torque. This was with the stock 10 degrees of base timing since we needed to keep the timing down with the nitrous. After the intake manifold, header, and x pipe system, power improved to 187, and torque was bumped up to 231. Those peak gains of 17 hp and 22 lb-ft are only part of the story, as we picked up everywhere under the power curve.
We took the little juiced coupe to the dragstrip as well, though-compared to our previous test-the results were slightly skewed due to the drop in average ambient air temperature. Our previous best elapsed times and speeds registered 15.12 at 92 on motor and 13.62 at 104 on the squeeze. These runs were made at Bradenton Motorsports Park in Bradenton, Florida, and at the time, temperatures were still in the high 80s.
Disconnect the various sensors...
Disconnect the various sensors and vacuum lines, and unbolt the upper intake plenum to remove it.
Fast-forward four weeks, and average temperatures had dropped to 65 degrees. On motor, our little black notch clicked off a 14.55 at 97 mph-a tasty improvement for sure and much more respectable given what 5.0 Mustangs are known for. Better still, we smoked a red C5 Corvette convertible, when we logged a nitrous-enhanced 13.06 at 111 mph with a 2.22 60-foot time. Sixth-tenths of a second in e.t. reduction and 14 more miles per hour through the traps sure had us smiling.
After seeing the 13.0 on the timeslip, we definitely wanted to make another pass to see if we could dip into the 12s. With the weather becoming even cooler, we pulled the spare tire and jack, and pumped up the front tires to 45 psi before pulling into the lanes.
When we got the call, we twisted the key and heard the click of a dead battery. The factory alarm then went off for about 10 minutes in the lanes while we hunted down jumper cables. The underdrive pulleys, combined with the use of the bottle heater, was apparently a little too much for the old battery, and after making such a scene in the lanes, we called it a night.
 Next up are the fuel lines....  Next up are the fuel lines. There are several different types of removal tools available at the local parts stores, but we prefer these plastic ones. You can use the Schrader valve on the line to depressurize the fuel system. |  Disconnect the fuel-injector...  Disconnect the fuel-injector wiring harness and pull it out of the way. Then remove the fuel rails and injectors. |  This is a good time to remove...  This is a good time to remove all of the intake sen-sors and the black heater rail from the lower intake manifold, as they can be difficult to take out once the manifold is off of the engine. These are all transplanted to the new intake. |