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2004 FORD SVT Mustang Cobra 281 supercharged MPG= 18.5 Hwy PDF Print E-mail
Written by Double Dragon
Friday, 08 October 2010 16:23

2004 FORD SVT Mustang Cobra 281 EFI supercharged MPG= 18.5 Hwy


Writing and photography copyright D. S. Brown.

Metric= 4.6 L engine- 12.7 L/ 100 km


EPA Gas mileage of the Cobra when new= 17 City/ 24 Hwy (pre 2008 EPA rating system). 15 City/ 22 Hwy MPG (revised EPA system)

04 cobra bob dr side

The acronym SVT refers to the Special Vehicle Team which is a performance division of Ford formed in 1993. SVT's first creations were the SVT Lightning trucks and SVT Cobras. SVT remains active with the Raptor trucks and Shelby Mustangs. In fact, the 2007 GT500 was originally on the drawing boards as a SVT Cobra when Carroll Shelby agreed to license his Shelby Mustangs through SVT. The Cobra was renamed GT500 after receiving some input from Carroll Shelby.

The 2003 SVT Mustang Cobra was code named "Terminator" during development and this appropriate nickname held fast after the public got hold of it soon after its Chicago Auto show debut on February 7, 2002. The 2003 and 2004 Cobra exceeded the performance of everything in its price range at the time.

Despite the well deserved nickname 'Terminator', the 2003 and 2004 Mustang SVT Cobras provide gas mileage nearly on a par with the Mustang GT from the same year. Comparing the Cobra to the other Mustangs and the Mach 1 for 2004, it comes out looking pretty efficient for such a powerhouse.

1) SIX CYLINDER MUSTANGS/ The 193 HP base 2004 Mustang V6 3.8 L (232 c.i.) running through a 4 speed auto squeezed out 19 MPG City/ 27 MPG Hwy according to the EPA system in effect at the time. The revised EPA system credits it with 17/ 25 MPG. The manual 5 speed improved the figures to 18/ 27 MPG using the new EPA system. 2004 model year Mustangs built after Oct 7, 2003 may have received the new 3.9 L (237 c.i.) version of the V6. The bigger V6 dropped figures to 17/ 24 MPG using the revised EPA system, but the manual 5 speed version matched the smaller 3.8 at 18/ 27 MPG.

2) MUSTANG GT AND MACH 1/ The 260 HP 4.6 L SOHC auto Mustang GT produced 17 City/ 25 Hwy MPG which is 15/ 21 MPG in the revised EPA system. The GT with a five speed gained 2 MPG highway. The Mach 1 had aluminum heads with DOHC to produce more power but received the same MPG ratings as the 5 speed GT.

3) SVT MUSTANG COBRA/ Despite packing an additional 130 HP from the same 4.6 L displacement, the Cobra managed to nearly duplicate GT mileage numbers posting 17 City/ 24 Hwy MPG which in the revised EPA system is 15/ 22 MPG. The Cobra shares the dual overhead cam cylinder head with the Mach 1 but the supercharger's ability to stuff in more fuel takes the mileage down a notch from the Mach 1. The additional weight of the supercharger and intercooler doesn't help either.

According to the EPA you only lose 3 MPG city and 5 MPG highway when you double the horsepower from the six cylinder to that of the supercharged Cobra. You lose nothing in city driving and 1 MPG highway when you toss in an extra 130 HP in the jump from GT to Cobra. The EPA site has data from two real life drivers of Cobras and the average MPG comes out at 17.5 for a mix of City and Highway driving. A forum on STANGNET.COM made up of Terminator owners generally agree 12-14 MPG is the usual range a Cobra gives city driving, and about 23 to 24 highway with 25 MPG possible driving conservatively.

Real world driving style tends to be more extreme for the SVT Cobra driver as compared to the average six cylinder driver. Magazine tests quoted below reflect the mileage you can expect when flogging the Cobra hard.

MOTOR TREND logged 12,187 miles on a long term test 2003 SVT Cobra convertible and averaged 14.3 MPG. The testers lamented poor ergonomics (difficult to reach shifter) and the typical poor fit and squeaks associated with the 25 year old design of the Fox platform. They did enjoy the car for what it is: a crude musclecar throwback to the 1960s era.

ROAD AND TRACK compared a 2004 Mustang SVT Cobra with the newly revived 2004 Pontiac GTO. The writer preferred the tougher looks and feel of the Cobra although he admitted the GTO was better put together with modern levels of fit and finish. The Cobra delivered 15.7 MPG in their test cycle.

What did SVT do to the 2003/4 4.6 L Mustangs to earn the name 'Terminator' while still achieving much better gas mileage than the old supercars that it outperforms? If you stay out of the supercharger, the engine performs nearly as frugally as the non supercharged 4.6. Just like the Grand National owners back in the 1980s that experienced decent city mileage as long as they didn't invoke the turbocharger, the Cobra driver can get normal gas mileage in relaxed driving. But if he wants insane power, it is there.

The SVT Cobras use an Eaton supercharged iron block version of the Ford 4.6 L (281 cubic inch) engine with better flowing Mach 1 DOHC aluminum heads to produce 390 HP and 390 foot pounds of torque. Inside, forged pistons and connecting rods are provided to withstand the force of supercharging. In an attempt to counteract some of the weight gain of the iron block, supercharger and intercooler the Cobra has aluminum flywheel and driveshaft. The hood and rear trunk lid with integrated spoiler are lightweight composite to further shave weight. Instead of the GTs five speed, the Cobra has a Tremec T-56 six speed manual transmission.

The Mustang GT solid rear axle is replaced with an independent rear suspension which helps the Cobra put every bit of that power to the ground. In street use the IRS exceeds solid axle Mustangs for traction. On drag strips using slicks wheel hop is a problem with the IRS. On tracks and twisty roads IRS keeps the car on the ground in concert with bigger 17x 9 inch aluminum wheels shod with 275/40ZR Goodyear Eagles combined with heavier 0.25 inch lower suspension and Bilstein shocks. Four wheel discs with 13 inch Brembo brakes up front round out the package taking the car down from 60 MPH to a stop in 116 feet (ROAD & TRACK did it in 121 feet)

Aside from the identity of the Cobra being proclaimed with a large COBRA insignia spelled out across the rear bumper where "Mustang" is usually displayed the rest of the appearance changes are subtle. The front and rear fascias are redesigned. The hood has a hump to clear the supercharger with functional flow through scoops to vent out hot air. The side scoops mimic the hood scoop using similar fins. The rockers have Cobra badges behind the front wheels. There are nice suede inserts in the leather seats with the Cobra logo embossed into them, brushed aluminum inserts replacing standard Mustang interior bits and very legible white face gauges which include a boost gauge.

A 2003 SVT Cobra convertible weighing 3,780 pounds rocketed MOTOR TREND testers from 0 to 60 in 4.8 seconds and ran the quarter in 13.12 at 109.5 MPH. MOTOR TREND credited the lighter Cobra coupe with quicker times (4.7 and 12.8 at 113.2) in an earlier article about the reborn 2003 Mach 1. AUTOMOBILE MAGAZINE noted that an electronic rev limiter stopped the car from exceeding an incredible 155 MPH. The Cobra AUTOMOBILE ran took 0-60 in 4.9 seconds and blasted the quarter in 13.4 seconds at 109 MPH. In June 2002 CAR & DRIVER managed to run a 2003 SVT Cobra even faster making it from 0-60 in 4.5 seconds. ROAD & TRACK got a 2003 Cobra SVT from 0-60 in 4.9 seconds and through the quarter in 13.3 seconds at 108.1 MPH.

The following year ROAD & TRACK coaxed a 2004 SVT Cobra to run 0-60 MPH in 5.0 seconds flat and run the quarter mile in 13.4 seconds at 107 MPH. 60-0 braking took 121 feet. Most enthusiasts quote a high of 4.5 or as low as 4.2 seconds to 60 MPH and high 12s in the quarter for Cobra coupes in bone stock factory condition.


OOCC Cobra Mustang MPG= 18.5 MPH Highway.

In 2009 Bob was out shopping for a car and decided the Terminator was the car for him. Black clearcoat with black top and black interior suits the mean reputation of the Terminators. Even with today's crazy fast musclecars this car stands out. Bob's Cobra is one of the 392 black Cobra convertibles built in 2004.

The door jamb sticker reveals the car's date of manufacture to be Feb, 2004. It is common to find stickers dated one month forwards or back of actual build month as the supply of labels is used up on the assembly line. Yes, the 2004 Cobra was an actual assembly line vehicle built in Dearborn, Michigan. The VIN starts with 1FAFP49YX4F. The significant digits of the VIN are not shown here to protect owner privacy.

1FA= Ford passenger car built in USA
F= Driver and passenger airbags and active seat belts.
P= Passenger car
49= Two door convertible Cobra
Y= DOHC Supercharged 4.6 L engine (the Mach 1 4.6 used an R, the GT 4.6 an X)
X= Check digit
4= 2004 model year
F= Dearborn, Michigan

The door jamb sticker tells us that the Cobra has a GVWR of 4,550 pounds (2,063 Kg) and maximum luggage and passenger capacity of 700 pounds (317 Kg) which means the curb weight is 3,850 pounds. It also calls for 32 PSI in the tires; lower than the usual 35 PSI request seen for regular Mustangs.

The Cobra's first registration on Jan 9, 2004 was theoretically made to the 'first' owner but it appears that this was a dealership. The Cobra was serviced March 18 and again May 5 of 2004. It was described as "dealer inventory" when sold June 10, 2004 to the 'second' owner. It is very likely that for the first six months of its life the Cobra was a demonstrator or registered to the wife of the dealer or some other typical arrangement. The 'second' aka first owner took it in for service on July 2, 2004 with a mere 1,994 kilometers showing. Those low miles support the hypothesis that the first private owner took possession June 10th. At this time a roll bar was installed in the car as seen below.

04 cobra bob roll bar

From here the mileage progresses normally. Service on Aug 12, 2004 shows 6,165 km (3,830 miles). Service on Nov 8, 2004 showed an odometer reading at 9,790 km (6,088 miles). The steering/suspension were checked as was the transmission. The transmission, clutch and clutch assembly was replaced. The Cobra had traveled a mere 6,000 miles and the guy has already blown out his transmission! We may assume that the car was being driven in an even more excessive manner than expected of these cars. On Dec 17, 2004 a four wheel alignment was performed along with replacement of the steering gear. The engine was checked at this time. The Cobra now showed 12,268 km (7,622 miles).

On Jan 9 of each year the registration was renewed until July 19, 2008 when the owner moved. On Sep 5, 2009 Bob enters the picture as owner number 'three' (in reality owner number 'two'). Bob acquired the car with some tweaks performed by the prior owner. The Cobra sported Borla exhaust and enhanced intake mods to provide deeper breathing and a snarl at idle followed by howls at speed. These two mods are commonly encountered on 'Terminators' and are good for as much as an extra 80 HP pushing the power up to 470 HP. Despite performance tweaks the Cobra easily passed the government emissions inspection Feb 15, 2011 at 50,000 km (31,068 miles). The Cobra also had a roll bar installed for track racing. Outside, a copy of the metal coiled Cobra logos that appear behind each front wheel stands in the center of the upper air intake below the hood where the Mustang running horse logo used to be mounted. This serves to identify the car as a Cobra, but mainly the smaller Cobra badge allows more air to pass into the engine compartment.

Take an SVT Cobra and put it in the hands of a perfectionist and enthusiast like Bob and what happens? The car gets cleaned and polished within an inch of its life. The perfectly maintained car also gets taken to the track for some serious racing. After surviving some serious flogging it is lowered one inch with new suspension, springs and wheels and tires.

04 cobra bob american wheels

The new Sumitomo HTR 35Z tires are mounted to 17 inch American rims. Bob saved the original Cobra chrome wheels which were a $695.00 option when the car was new. Those original wheels are pretty nice looking but on the track the new set up provides a greater margin of cornering power. The original wheels try to retain some vestige of the original 1960s flavor by using 5 fairly broad spokes instead of the modern trend towards 'spider wheels' with complex mazes of thin spokes.

04 cobra bob orig wheels

Bob saved his original wheels but he couldn't save the original ride height. A Cobra is already lower than a stock Mustang. Take away another inch and the Borla exhaust is menaced by road irregularities requiring some serious caution on speed bumps.

The only modification Bob would prefer to have avoided was made at the request of the police. The Cobra has no provision for a front license plate. The prior owner most likely used this car exclusively for track racing and hence escaped the wrath of the police. Bob didn't get away with driving the Cobra on the street for long with the front plate placed on top of the passenger side dashboard. Two holes had to be drilled into the pristine original front fascia in order to attach the license plate.

Every drive in this car is an experience. An appropriate CD and an exciting route are selected and off he goes. When he first got the car Bob made sure there was never a corner or hill where the car wasn't pushed right to the ragged edge. Shifts frequently didn't happen until nearly 7,000 RPM and the sound of the supercharger spooling up was a common part of the driving experience. Bob's son summed up a track day,

"There were about four or five cars clustered together and after two turns Bob was so far ahead he drove the rest of the course alone. No one could catch him. There was smoke pouring off the brakes when he came into the pits!"

After a few years of ownership and sufficient quantities of adrenalin the Cobra now mainly enjoys some moderate back country road cruising. The vast power is put to good use when selecting a comfortable position on the highway. Third gear will get Bob past just about anything on the road. As he says,

"I'm looking for an open place to cruise without being boxed in by self appointed traffic police. I vastly prefer being out in front of the maddening crowd than stuck in the middle of the pack."

The current driving style employs quick cruising speeds in sixth gear (0.63 overdrive) with some bursts of full throttle in third gear to circumnavigate the herds. Bob's preferred brand is Chevron 94 octane but for the fills recorded here the car burns 91 octane from the Co-op gas station chain. Bob changes his oil every 5,000 Km (3,000 miles) using Royal purple 5W20 full synthetic. The full synthetic oils provide better high temperature protection and reduce internal engine friction which improves MPG. The roll bar adds a few pounds to the car. Most of the driving was done in hot temperatures, on dry roads with the convertible top down carrying no cargo aside from the 220 pound driver which puts the weight a little over 4,000 pounds.

Kilometers  Gallons   Octane  Full Tank?   MPG (uncorrected)

64,644.8        13.2      94      Full tank     N.A.
65,087.5        14.9      94      Full tank     18.45 MPG



Last Updated ( Wednesday, 03 September 2014 10:52 )