Some Simple Additions To Our Supercharged GTO Yield 54 Rwhp--Without Having To Increase Boost
We left you last time with our 2004 GTO making 447 rwhp with nothing more than an SLP cat-back exhaust and an off-the-shelf Vortech supercharger kit helping to up the ponies. These power-adding parts were enough for the near-4,000lb GTO to run 12 flat in the quarter. ("Back in Black Part 5," November 2005)
Given the nature of manufacturer-supplied computer programming, we knew a good amount was still left on the table. For instance, ignition timing was set very conservatively, in the range of 8 degrees. The reasons for Vortech doing this are understandable, as no two cars are alike. But we decided that to get the most out of this kit, we'd need to custom-tailor the computer tune to our application.
Renowned Corvette tuner East Coast Supercharging volunteered to lend us its services in upping the ante on our blown Goat. Located in the heart of the Garden State, owners Chris Coriell and Douglas Ring have quickly built their business into one of the premier shops in the country for late-model Vette tuning, supercharger systems, and stroker motors.
While nearly all of the newfound power would come from customized fuel and ignition maps from ECS, there were a few other loose ends to tie up to ensure that this endeavor could proceed with the utmost safety. Specifically, we decided to "key" the harmonic damper/crank pulley assembly, install a low-temperature thermostat, put in some colder spark plugs, pop in some fatter fuel injectors, and last but certainly not least, upgrade the factory fuel system. With these simple mods, we'd have enough gas and some other extra safety measures to guarantee very safe power increases.
We'll explain the significance of each of these modifications as we go through their installation in the photo captions. It's important to know that without each and every one of the mods it took to get there, there's a good chance we'd have ended up with a damaged powerplant. So in the spirit of not overlooking the details, read on--carefully! Catch us next time when we improve on this a bunch more with a set of long tube headers from SLP--the gains just keep a comin'!