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2008 Speedfactory Vortech Supercharged Dodge Challenger SRT8 Full Test

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    2008 Speedfactory Vortech Supercharged Dodge Challenger SRT8 Picture

    Sure the Speedfactory's Vortech supercharged Challenger SRT8 will fry the rear tires. What's surprising is that the road itself didn't spontaneously combust. | November 03, 2009

Road Test

2008 Speedfactory Vortech Supercharged Dodge Challenger SRT8 Full Test

Something Wicked This Way Blows

    2 Ratings
    These days, carmakers are obsessed with being friendly. Environmentally friendly, kid-friendly, fuel-friendly. This year's Detroit auto show may as well have been group therapy with a big hug at the end.

    Then there's this 2008 Speedfactory Vortech supercharged Dodge Challenger SRT8. This car isn't nurturing, it doesn't want to comfort anyone and it looks like it just started a prison riot. This car is loud, thirsty and completely out of sync with the Greenies and the Weenies. It's all the best antisocial tendencies wrapped up in one big black Mopar.

    This is what dream cars used to be: all attitude, big damn engine, no recyclable canola bean upholstery. You know, back in the good old bad old days when a 560-horsepower, 4,000-pound, V8-powered rear-wheel-drive muscle car made you the envy of your friends, not the destroyer of Mother Nature.

    Yeah, we like it, too. Let's go for a ride.

    Badass and Ballsy
    Press the Speedfactory Challenger's start button and the car growls into a rumbling idle. Redneck music. Sounds like the pace lap at a North Carolina dirt track. There's so much torque even at this low engine speed that the car rocks on its lowered suspension. Then there's the churning whine of the Vortech centrifugal blower. What that sound lacks in mellifluous beauty, it makes up for with pure grinding menace.

    It's that gnarly supercharger that's the star of this car. It's Vortech's V-3 Si-Trim centrifugal blower and it's the only real piece of hardware included in Speedfactory's Stage 1 package, which costs $11,995. In the tested configuration, the supercharger force-feeds 6.5 pounds of boost to the 6.1-liter Hemi V8. That's enough, claims Vortech, to whip output up from 425 to 560 hp with a commensurate increase in peak torque production up to 510 pound-feet.

    Aiding in keeping the air-fuel mixture dense and rich in oxygen is an air-to-water "Charge Cooler" (Vortech slang for "intercooler"), while oversize injectors heave in the fuel and the engine control computer's programming has been tweaked using a DiabloSport Predator handheld electronic tool. A JBA cat-back exhaust system provides the basso profundo voice.

    The supercharger installation is straightforward in the Challenger SRT8, if not particularly elegant. The well-finished blower hangs off the driver side of the Hemi, while the plumbing snakes back through the Charge Cooler and forward to the throttle plate and stock intake manifold. That's a bit convoluted and it kind of overwhelms the engine bay. This isn't the supercharger system to buy if you expect a lot of future spark plug changes. But there's little problem with oil lines, since the V-3 Si-Trim compressor has its own internal oil reservoir.

    All that power goes through the Challenger SRT8's standard five-speed automatic transmission (with AutoStick shifting), then on to a set of Richmond Gear 3.55:1 final gears in a limited-slip differential. Half-shafts from BMR Fabrications handle the additional twist.

    Taming the Beast Within and Without
    You can throw a bunch more power into any car — even a car as normally composed as the Challenger SRT8 — without some fortification of its handling, but we don't recommend it. Extra-cost options on this black Challenger include KW Variant 2 coil-over shocks, which lower the car over a set of optional Boze alloy wheels — 20 by 8.5 inches in front and 20 by 10 inches in back. In turn, those wheels are wrapped in 245/45R20 front and 275/45R20 rear Yokohama Parada Spec-V tires.

    As it is with the untouched Challenger SRT8, the big disadvantage for Speedfactory's car is weight. On Inside Line's scales, the Speedfactory Challenger porked in at a thickset 4,251 pounds — 2 tons and a fat guy — with 56 percent of that plopped atop the front wheels. Newtonian physics being the unforgiving whack jobs they are, that's a lot of weight to kick around, even for 560 hp.

    Porcine though it is, the 2008 Speedfactory Challenger is gorgeous. Lowered over those blinding wheels, it looks the way a Challenger should look — nasty, evil and ready to commit multiple felonies. Of particular appeal is the deep dish to the wheels. The rather slab-sided 21st-century Challenger really needs that depth to bring out the character of its otherwise voluptuous 20th-century shape. The wheels also frame and flatter the SRT8's standard Brembo front brake calipers.

    Blistering and/or Burning
    Yokohama Paradas are among the world's very finest performance tires. But when the Vortech blower kicks in on the Speedfactory Challenger as the tach needle sweeps by 3,200 rpm, they're just hopeless. There have been tsunamis that have struck with less suddenness than the Vortech's boost.

    At the drag strip we would really ease the car off the line, walking it away from a stop at under 1,200 rpm. Do this and it accelerates normally for a moment, then the blower erupts, and instantly the rear tires squirm and squirrel as if they've been blown apart by bazooka fire.

    Still, despite those severe traction limitations, zero to 60 took just 4.3 seconds (4.1 seconds with a foot of rollout like on a drag strip) and the quarter-mile ripped by in a white-knuckled 12.2 seconds at 119.5 mph. Those are profound improvements over the standard Challenger SRT8's 5.1-second 0-60 time and 13.2 seconds at 107.5 mph quarter-mile performance. But there's more to this story....

    Knowing too well that its Challenger would be severely traction-limited, Speedfactory also brought along a set of Nitto 555R drag radials on the standard wheels (and in the same sizes as the Yokohamas). For going in a straight line, the Nitto tires proved a godsend — they provided much more traction, tracked straight and remained stable at speed. And they also proved much quicker.

    With the Nittos, the 0-60 time dropped to just 3.8 seconds (an incredible 3.4 seconds with a foot of rollout like on a drag strip) and the quarter-mile blew by in 11.8 seconds at 119.8 mph. That's exotic-car territory — right there with the Chevrolet Corvette Z06, Dodge Viper SRT-10 and Ford GT. And none of those machines are anywhere near as big or heavy as the Speedfactory Challenger.

    In fact, there's so much frontal area on the heavyweight Challenger that as the Speedfactory example ripped by during testing, it was almost possible to feel the air being pushed aside. It's the sort of sensation one might expect from a rocket-propelled boxcar. That is, if the boxcar was taken off its rails before the rocket was lit.

    Evil for Evil's Sake
    With its tire-roasting power, fantastic sound and aggressive and provocative looks, there's a lot to love about this Speedfactory Vortech Dodge Challenger SRT-8. But there are also limits to that love.

    This isn't a car that is easy to throw around like a Miata or even a Mustang; it's just way too big. The supercharged power obviously makes the car more athletic, but even the largest driver can feel swallowed up in the Challenger's tall sills and restricted greenhouse. The seats are comfortably shaped, but the driver still shifts around too much as the car slews through IL's slalom at a modest 60.2 mph. The 0.80g skid pad orbit isn't much of a bragging point either.

    But most unforgiveable is the loss of ride comfort that comes with lowering the Challenger. Frankly, no one here expects the Challenger to be a handling champ — it's not that kind of car — but in stock form, the big Dodge is one of America's greatest ground-gobblers. Losing the ability to comfortably swallow half a continent's worth of interstate highway over an afternoon is a pretty big price to pay for the snarky stance. Speedfactory ought to take a look at alternative methods for achieving the same look while sustaining more comfort.

    The brakes are stock. Which means they work. And work well. Best stop from 60 mph was 118 feet. Although the pedal is too soft for our taste, fade is not a problem. Impressive, considering the Challenger's heft.

    Evil Costs Bucks
    Throw in all the pieces and labor to bolt them on, and Speedfactory will sell you a clone of this Challenger for $23,475 plus one stock Challenger SRT8. Or you could just go for the supercharger system, which is available through Vortech for $6,400 (plus installation if you don't want to do it yourself). And yes, Vortech also has a similar kit for the 5.7-liter Hemi in the Challenger R/T.

    Evil, it seems, is like speed. It costs money. How evil do you want to be?

    The manufacturer provided Edmunds this vehicle for the purposes of evaluation.

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    malik14 says:

    05:50 PM, 10/24/2009

    Style: 10
    Performance: 8
    Value: 4
    Overall: 22 out of 30

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    Speed Read

    Featured Specs

    • 560-horsepower supercharged Hemi V8
    • Five-speed automatic transmission
    • 4,251-pound curb weight

    What Works

    It's fast, it looks stupendous, sounds like a billion bucks and does everything a supercharged Challenger should do.

    What Needs Work

    The supercharger doesn't make it smaller or handle better. Rough ride.

    Tags

    Specs & Performance

    Vehicle
    Model year2008
    MakeDodge
    ModelSpeedfactory Vortech Supercharged Dodge Challenger SRT8
    StyleSRT8 2dr Coupe (6.1L Supercharged 8cyl 5A)
    Base MSRP$52,540
    Estimated MSRP$64,020
    Options on test vehicleBoze wheels and Yokohama Parada Tires ($5,095), KW Coil-Over Suspension ($1,995), Richmond Gear 3.55:1 Final Drive Gearset ($1,695), BMR Fabrications Billet Half-Shafts ($2,695)
    Drivetrain
    Drive typeRear-wheel drive
    Engine type90-degree V8
    Displacement (cc/cu-in)6,059cc (370 cu-in)
    Block/head materialCast iron/aluminum
    ValvetrainOHV, 2 valves per cylinder, Vortec V3 Si-Trim supercharger
    Compression ratio (x:1)10.3
    Redline (rpm)6,400
    Horsepower (hp @ rpm)560 @ 6,000
    Torque (lb-ft @ rpm)510 @ 4,800
    Fuel typePremium unleaded (required)
    Transmission type5-speed automatic
    Transmission and axle ratios (x:1)I = 3.59, II = 2.19, III = 1.41, IV - 1.00, V = 0.83, FD = 3.55, R = 3.16
    Chassis
    Suspension, frontIndependent, double wishbones, coil springs and stabilizer bar
    Suspension, rearIndependent, multilink, coil springs and stabilizer bar
    Steering typeSpeed-sensitive, hydraulic-assist, rack-and-pinion power steering
    Steering ratio (x:1)16.1:1
    Turning circle (ft.)38.9
    Tire brandYokohama -- Nitto
    Tire modelParada Spec-Y, [Nitto NT 555 Extreme ZR (front) and NT 555R Extreme Drag (rear)]
    Tire typeSummer, [Drag Radial]
    Tire size, front245/45R20 99V (34 psi), [245/40ZR20 99W (37 psi)]
    Tire size, rear275/40R20 106V (35 psi), [275/40ZR20 102V (18 psi)]
    Wheel size20-by-8.5 inches front -- 20-by-10 inches rear
    Wheel materialForged two-piece aluminum
    Brakes, front14.2-inch ventilated disc, 4-piston fixed calipers
    Brakes, rear13.8-inch ventilated disc, 4-piston fixed calipers
    Track Test Results
    Acceleration, 0-30 mph (sec.)2.1, [1.8]
    0-45 mph (sec.)3.2, [2.7]
    0-60 mph (sec.)4.3, [3.8]
    0-60 mph, mfr. claim (sec.)5.7, [5.2]
    0-60 with 1 foot of rollout (sec.)4.1, [3.4]
    1/4-mile (sec. @ mph)12.2 @ 119.5, [11.8 @ 119.8]
    Braking, 30-0 mph (ft.)30
    60-0 mph (ft.)118
    Slalom, 6 x 100 ft. (mph)60.2
    Skid pad, 200-ft. diameter (lateral g)0.80
    Test Driver Ratings & Comments
    Acceleration commentsWith the Yokohama street tires, the car was extremely difficult to launch all the way to the top of 1st gear because of the atomic boost that hits between 3,000 and 3,500 rpm. Anything above a 1,250-rpm launch roasts the tires, and anything less bogs it out of the hole. Tiptoeing on traction all the way until 2nd gear hits is a trial-and-error ordeal. We call it "threshold throttle." Upshifts from the stock SRT8 transmission are as brutal as I remember, but scratch hard on both 1-2 and 2-3 shifts. Switching to the Nitto Extreme drag tires, the car got a whole lot easier to launch, especially as the tires heated up with each successive run, but it still required a delicate touch. The boost at the top of 1st gear became less of an issue so I could go to WOT sooner. With either tire, however, 3rd gear felt like it laid down a bit, and even the supercharger can't overcome the tall gear ratio.
    Braking ratingVery Good
    Braking commentsTypical SRT8 initial bite and ultimate stopping power, but the pedal felt like it traveled farther than stock (worn pads?). Decent fade resistance until the 20th (?) quarter-mile run at over 120 mph when the pads started smoking and the pedal went flaccid -- but I guess that's still pretty impressive for the amount of abuse we gave it.
    Handling ratingPoor
    Handling commentsSlalom: Something got lost in translation here. This Challenger has far more understeer than a stock one. Huge understeer on each cone and I even whacked one so hard it disconnected the left front foglight. Sorry, guys. Understeer means the ultimate slalom speed was limited by the front of the car so a slow-in/fast-out technique was the only one that worked. No amount of power will overcome this car's plowing ways. Skid pad: As "safe" as it feels, the excessive understeer is steady and stubborn. I couldn't even manage to kick the rear out by lifting abruptly and whacking the throttle to the floor. Something ain't right here when you can't powerslide a 500-plus-horsepower car.
    Testing Conditions
    Elevation (ft.)1,121
    Temperature (°F)49, [56]
    Relative humidity (%)65%, [45%]
    Wind (mph, direction)0
    Fuel Consumption
    EPA fuel economy (mpg)13 city/18 highway
    Edmunds observed (mpg)N/A
    Fuel tank capacity (U.S. gal.)19.0
    Dimensions & Capacities
    Length (in.)197.7
    Width (in.)75.7
    Height (in.)55.1 (est)
    Wheelbase (in.)116.0
    Track, front (in.)63.0
    Track, rear (in.)63.1
    Legroom, front (in.)42.0
    Legroom, rear (in.)32.6
    Headroom, front (in.)39.3
    Headroom, rear (in.)37.4
    Shoulder room, front (in.)58.2
    Shoulder room, rear (in.)53.9
    Seating capacity5
    Cargo volume (cu-ft)16.2
    Max. cargo volume, seats folded (cu-ft)Standard 60/40 split fold (volume not specified)
    Warranty
    Bumper-to-bumper3 years/36,000 miles
    Powertrain3 years/36,000 miles
    Corrosion5 years/100,000 miles
    Roadside assistanceNot available
    Free scheduled maintenanceNot available
    Safety
    Front airbagsStandard
    Side airbagsNot available
    Head airbagsStandard front and rear
    Knee airbagsNot available
    Antilock brakes4-wheel ABS
    Electronic brake enhancementsBraking assist, electronic brakeforce distribution
    Traction controlStandard (disabled)
    Stability controlStandard
    Rollover protectionNot available
    Tire-pressure monitoring systemStandard tire-pressure monitoring with 4-corner readout
    Emergency assistance systemNot available
    NHTSA crash test, driverNot tested
    NHTSA crash test, passengerNot tested
    NHTSA crash test, side frontNot tested
    NHTSA crash test, side rearNot tested
    NHTSA rollover resistanceNot tested
    IIHS offsetNot tested
    CollapseSpecs and Performance Expand Collapse

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