It's an unforgettable grinding whine. Sort of like a puma's growl before it pounces, but more menacing, higher pitched and just evil. And it comes when this 2010 Chevrolet Camaro SS by Vortech Engineering starts up and its 6.2-liter V8 settles into an idle. Nothing sounds quite like a Vortech centrifugal supercharger.
In this case it's the same V-3 Si-Trim blower from Vortech Engineering that had been bolted into the Speedfactory supercharged Dodge Challenger SRT8 that we drove last January. Some people would want to pull out their molars if they had to listen to the persistent scream of a centrifugal supercharger. Others would record the sound and put it on their iPod. Either way, it's a distinctive, intimidating sound, so different from a turbocharger or even a Roots-type supercharger. Bolt a Vortech supercharger up to any car's engine, and the well-educated world knows what's under the hood even before it's opened.
So we have the Vortech supercharger here, and it's working with the 6.2-liter V8 of the 2010 Chevrolet Camaro SS. We're expecting the sort of performance that flattens eyeballs, cracks open skulls and inspires Alan Jackson songs. This combination should work even better because this particular Camaro is equipped with a six-speed automatic transmission.
No Shift, Sherlock
Vortech Engineering has been in the supercharger business for a long time, and it knows that the 2010 Chevrolet Camaro SS will be sold with a lot more six-speed automatics than six-speed manuals — something like four automatics to every manual, in fact.
But the automatic Camaro SS carries GM's L99 V8, which is rated at 400 horsepower at 5,900 rpm, while the manual Camaro SS gets GM's LS3 V8, which is rated at 426 hp at 5,900 rpm. Meanwhile, the L99 also produces a bit less torque than the LS3 V8, 410 pound-feet of torque at 4,300 rpm compared to 420 lb-ft of torque at 4,600 rpm. Compression ratio is the big difference, as the L99 runs at 10.4:1, while the LS3 squeezes tighter at 10.7:1. Also the L99 engine runs GM's Active Fuel Management, which deactivates cylinders under light throttle loads to improve fuel economy.
The L99's slightly lower compression ratio and slightly lower torque peak both work to the advantage of the Vortech installation, however. First, the slightly lower compression ratio makes the engine more compatible with forced induction because there's less risk of detonation. Second, a centrifugal blower is more effective at higher rpm than a Roots-type blower (as used in Hennessey Performance Engineering's HPE550 Camaro), so its characteristic blower heave past about 4,000 rpm works well with a torque curve that's meatier at the bottom end.
And as far as GM's cylinder deactivation system is concerned, we didn't detect any problems.
Blow by Blow
A compact centrifugal supercharger is easier to package than a big Roots-type blower, so the Vortech Engineering installation is a neat piece of complicated packaging. The V-3 supercharger sits on the left side of the engine bay and is bolted to the engine by two plates of billet aluminum. It sucks air through a custom roto-molded cold-air induction system, then sends the compressed air charge through a 3-inch mandrel-bend aluminum tube to an air-to-air intercooler that sits just below the front bumper. From there, the compressed air has a straight shot back up to the throttle body and into the cylinders.
Driving the blower is a 10-rib belt that runs down to a pulley on the crank. An automatic tensioner keeps the belt taut and a new crank damper smoothes out any vibration from the bigger bangs in the cylinders.
To feed the engine the greater volume of fuel it needs, Vortech replaces the injectors with high-flow units and then reflashes the memory in the Camaro's engine control computer to deal with the onslaught. A Vortech bypass valve is plumbed in to keep boost levels down at 8.5 psi. The result is 603 hp at 5,900 rpm and 518 lb-ft of torque at 4,300 rpm.
Besides the supercharger system itself, the only changes to this 2010 Chevrolet Camaro SS have been the addition of a mellow-sounding Corsa cat-back exhaust system ($1,599.99, not including $200 installation) and a pair of 275/40R20 Nitto Extreme Drag NT55R tires ($584). Vortech didn't touch the suspension and the car even wears the same wheels Chevy bolted to it on the assembly line in Oshawa, Ontario.
But it's not the drive belt, pipes or programming that matter. It's the speed.
Blast to Last
With the shift lever in Drive and a drag strip technique that consists of planting the accelerator and getting a death grip on the steering wheel, this vicious beast blasts from zero to 60 mph in just 4.1 seconds (3.8 seconds with 1 foot of rollout like on a drag strip). The quarter-mile simply vanishes in 12.33 seconds at 115.4 mph.
The obvious comparison here is to the Chevrolet Camaro HPE550 by Hennessey Performance Engineering, another supercharged monster. That machine, running a six-speed manual transmission, was a bit quicker over the quarter-mile, doing the deed in 12.1 seconds at 120.1 mph. But it is behind the Vortech automatic in the 0-60 contest, since it takes 4.3 seconds (4.0 seconds with 1 foot of rollout like on a drag strip) to accomplish the feat.
For the record, the Vortech Camaro is much quicker than a stock Camaro SS. It's a full seven-tenths of a second quicker to 60 mph than our previous SS test car, which came equipped with a manual transmission. (In fact, the Vortech Camaro is the first Camaro SS we've driven with the automatic transmission.)
But the numbers only tell part of the story. The Hennessey-built Camaro is an absolutely vicious brute. It's the sort of machine that sends children scurrying for cover and can punish a driver for a moment's inattention. On the other hand, the Vortech machine is equally quick and yet laid-back at the same time — it's more manageable and easygoing.
This Camaro's automatic transmission is an important part of the equation. Vortech has done an outstanding job of matching the engine with the transmission. Left in Drive and with part throttle used, the engine will rev to somewhere just north of three grand and shift — no real boost effect is felt. Left in Drive and with the throttle floored, the engine will hit the boost at about 4,000 rpm and scream to 6,000 rpm before shifting with a satisfying whump. And if that's not enough, the transmission can be shifted to a manual operation mode that lets you choose your gear with trigger switches on the backside of the steering wheel spokes. Overall, there's some deterioration in throttle application linearity (when the blower hits, it hits hard), but around town this Camaro will putter along like a Cushman scooter.
Smokin'
To some peculiar minds, the essence of any supercharger installation is the ability of the car to generate massive blue-gray clouds of tire smoke in a burnout. Surprisingly enough, it takes some very specific techniques to get the Vortech Camaro to generate a haze of burning rubber.
Turn off the stability control, hold down the brake pedal and hit the accelerator pedal, and the engine will rise to 2,000 rpm and just spin steadily while the brake pedal seems to press back against your foot as if the car is trying to break free. This is, after all, an engine computer programmed by GM to avoid warranty problems.
So to generate the smoke, it takes a light touch on the brake — just enough to lock the front wheels — and a light, progressive touch on the throttle. Done right, the engine will climb into the meat of its power band and generate enough smoke to make even burnout connoisseurs shudder in giddy ecstasy.
But for most of us, burnouts are just a stunt — a fun way to burn off some tire tread. A burnout probably isn't enough of a reason to send $6,960.50 to Vortech Engineering, Inc. for its supercharger kit for the 2010 Chevrolet Camaro SS and then set aside about $1,500 for the installation. The better reason is that Vortech hardware makes an already quick car into the 2010 Chevrolet Camaro SS Supercharged by Vortech Engineering, which is a serious challenger to Vipers and Ferraris.
And while it sounds nasty, it runs sweet.
