With up to 30 psi of boost on tap, the decision was made to build up the stock 4G63 block with high-strength Eagle rods and Arias 9.0:1 racing pistons. Up top, HKS 272-degree cams with adjustable cam gears, along with 1mm oversized Ferrea valves, springs and titanium retainers fill the head, which was ported by Ultimate Racing to free up top-end power and raise the rev limit to a wild 9500 rpm. Also, the stock balance shafts were removed to reduce reciprocating mass.
With big boost and a 65-hp shot from a Nitrous Express wet nitrous system on tap, the fuel system needed to be upgraded to keep up with this machine's thirst for C-16 race gas. A set of 900cc injectors and an Ultimate Racing twin pump in-tank fuel system were plumbed with -8AN fuel line, a custom BJ's fuel rail and some very masterful hose routing and fabrication. An AEM stand-alone EMS system was installed to provide tuning control and data logging capability.
All this power hitting the ground led to several significant setbacks at the track with clutch and drivetrain failures. The characteristics of a heavy car with significant turbo lag requires a high-revving launch method that put tremendous loads on the drivetrain, particularly in a full-weight street car such as Ivan's Evo. Several front transfer cases were sacrificed to the quarter-mile gods while seeking the elusive 10-second pass.
Mitsubishi, perhaps capitalizing on the new market, did not service the individual parts in the front differential and the only way to repair a broken front differential was to replace the entire front transfer case. After spending about $1800 each on two replacement front transfer cases, mechanic, Papotec went experimental. Ingeniously, he disassembled several different factory Mitsubishi transaxles looking for parts to match the factory Evo VIII gears. After much dissection, he found that Mitsubishi Mirage spider gears matched up perfectly with the Evo's. This opened up a huge supply of inexpensive replacement gears.
A Phantom Grip LSD was added to the stock open differential to improve traction off the line and reduce dreaded wheel hop, which is the cause of most drivetrain damage in Evos. Finally, an APS twin-disk carbon clutch with push-style conversion was added to handle the increased power.
Papotec also theorized that by introducing the nitrous off the line, the launch rpm could be lowered. Leaving the line at a lower rpm means less stress on key driveline components. Although this approach may defy conventional wisdom for FWD and RWD cars, on the AWD platform the use of nitrous in conjunction with the larger turbo and careful tuning results in very consistent and predictable off-the-line performance. The key is to tune the car to have the nitrous and boost hit in a smooth, controlled manner. The nitrous system would spray using a progressive strategy executed by the AEM EMS, tailing off as boost climbs.
After months of hard work the project was finally completed on May 9, 2005 when Gadiel worked his magic on the AEM at Sporty Dyno in San Juan and pulled 612 whp out of his hat. The very next day Ivan took to the famous Carolina Raceway Park and set down the record-setting 10.99 at 132 mph pass. Redemption was sweet as Ivan proudly demonstrated to the STi doubters that his Evo was a force to be reckoned with. There is no end in sight for this project as many fellow Evo fanatics in Puerto Rico are gunning for the title of Fastest Evo VIII in Puerto Rico. Ivan and his pals have become addicted to the process of discovery and their mission is to learn more about how the 4G63 works and discover new ways of making more power.
Another thing that really impressed me about this machine is its stock-like driveability and idle quality as I was given a drive to our photo location. The AEM stand-alone ECU, or more specifically the tuning by Gadiel, handled the 900cc injectors, built engine and cams yet produced a car your grandmother could easily drive to the store. Speed is impressive, but the ability to produce intoxicating power levels while maintaining an OEM-like feel and function is the sign of careful parts selection and tuning which really sets this EVO apart.
What is equally impressive is that the two men responsible for wrenching and tuning this machine, Papotec and Gadiel, work out of their home garages and turn wrenches only as a second nighttime job. Gadiel is a mechanical engineer by day and tuner by night. Being the man behind the lap-top, tuning this Evo and also the physics-defying STi of "Big Valley" Victor, the fastest STi in Puerto Rico, which goes 10.2 at 142 mph, has really helped Gadiel become one of the island's top tuners. It is the commitment to the hobby illustrated by Ivan, Papotec, Gadiel and many other enthusiasts I met that puts Puerto Rico on the leading edge of the scene.