Corvette STS C5 Turbo Kit - After-Burner

One of the more common criticisms of other STS kits is that they position the air filters too close to the ground, where water ingestion could conceivably be an issue. In the C5, the filters are mounted high up in the rear bodywork, just behind the taillights. A pair of Outerwears pre-filters (not shown) furnish an additional level of protection.

The C5 kit comes with this 48-tube front-mount intercooler, which features a 29-inch-wide core and purportedly cools the intake charge to within 10 degrees of ambient. STS claims that the overall pressure drop from turbos to engine is an impressively low 3 psi.

Thomas' system was optioned up with this TiAL blow-off valve ($300). In addition to keeping the turbos on the boil between shifts, the BOV emits a cacophony of pops and hisses guaranteed to earn you "mad street cred" with the slammed-Civic crowd.

Thanks to the noise-attenuation properties of the turbochargers, the STS kit obviates the need to run mufflers. It does, however, include this rear-section exhaust system, which eructed a deliciously nasty snarl through its 4-inch polished tips.

Tucked away beneath the rear-bumper cover, the Garrett turbochargers are all but invisible to the casual observer. Note the heat-retaining coating on the turbocharger-discharge pipe.

Shortly after this picture was taken, that nifty carbon-fiber air bridge blew apart during a dyno pull-the second such failure to occur in as many days. (The plastic stocker was the first victim.) Lovell plans to install an aluminum BBK bridge to prevent similar pyrotechnics in the future.

With all the turbo hardware socked away out back, the C5's engine bay stays cool and remarkably tidy. And aside from some minor trimming of the fenderwell liners, the factory bodywork escapes the installation process unscathed. Lovell needed around 12 hours to complete the job-it was one of the first production kits in the United States, after all-but feels confident he can slash that time by a few hours next time around.

Thomas' system also included this progressive methanol-injection kit, which came with a C5-specific harness and commanded an extra $499. With the kit in place, Lovell was able to dial in more boost without fear of detonation.

High-Boost Setting with Methanol Injection With the kit having already eclipsed the 525-rwhp mark, Lovell decided to nudge the absurdity meter even higher with the optional progressive methanol-injection kit. With the turbos now safely spooling out 9.6 psi of meth-chilled boost, output shot to an unconscionable 600.4 hp and 543 lb-ft at the rear wheels. With a little more tuning work, Lovell thinks the 650-rwhp mark is well within reach. Still need more? STS offers multiple turbo upgrades capable of supporting up to 1,500 hp.