Extreme (ik strem) adj. [< l. Exterus, outer] 1. Farthest away, utmost 2. Very great excessive 3. Unconventional or radical, as in politics (or tuning) 4. Harsh; drastic.
Extreme is a words that really packs a punch and it ably describes this wicked EVO VIII. The Mitsubishi Lancer Evolution VIII really packs a punch right out of the box and its 4G63 engine is a well-known entity in America from its days powering Eclipse/Talons. As good as any factory turbo engine is, there are always enthusiasts poised to boost it up.
George Marinov of Boost Solutions in Suwanee, Ga., is just such a soul. He personifies extreme and threw the sizing chart out the window as he set off to fit the biggest HKS turbo to the Mitsubishi's diminutive 2.0-liter engine, add humongous 1680cc injectors, get the thing to idle, and live at full boost.
The turbo in question is HKS's intimidating T51R SPL with a ball-bearing center section. The T51R sports a huge 102.2mm compressor wheel and an 82mm turbine wheel in a 1.00 A/R housing. Boost Solutions had to manipulate the HKS exhaust manifold to coax the large-frame turbo in the crevice between the engine and the radiator.
"The bigger, the better!" touts Marinov. "The HKS T51R SPL is the biggest turbo HKS makes. It's a common turbo for Skylines and Supras. On the 4G63, it spools faster than we expected. It barely fits in the bay, since we're keeping the power steering and the stock radiator. If we get a different radiator, then the car will get an Innovative GT88 dual ball-bearing or similar."
The remainder of the turbo system is made up of an HKS Racing S/S wastegate, twin SSQV blow-off valves, custom four-inch intake piping, an 80mm Accufab throtlebody and a four-row GReddy front-mount intercooler.
The next big hurdle was fueling the Godzilla-like hairdryer. A custom fuel rail fitted with -8 AN fittings was fabricated to supply the monstrous 1680cc Bosch fuel injectors. A Weldon 2035 fuel pump, rated at 220 gph, feeds the system, which is commanded by an AEM EMS.
The Mitsubishi 4G63 was stroked to 2.3 liters by filling the block with custom Pauter rods
A pair of HKS Super Sequential blow-off valves relieve the pressure between shifts. The T5
The EMS controls all aspects of engine operation from boost to fuel to ignition. Marinov credits the system for achieving acceptable idle characteristics and civil driveability until the hammer is dropped. A 5-bar MAP sensor and AEM UEGO controller ensure proper metering and a healthy air/fuel ratio.
Boost Solutions also heavily reworked the cylinder head to get the most out of the stratospheric boost flowing through its passages. The ports were matched and runners polished.
The engine was tuned first for 20 psi (base boost), and then we ran 24 psi, 28 psi and 32
A high-flowing exhaust system is key considering the volume being generated by the 4G63. B
Boost Solutions added 1mm-over stainless Ferrea valves, Ferrea dual valve springs and titanium retainers. Valvetrain orchestration is handled by Tomei Pro cams with 11.5mm lift and 260 degrees of duration that are fine-tuned with Tomei adjustable cam gears.
With the big boost on tap, Boost Solutions upgraded the 4G's internals and took the opportunity to bore and stroke the engine out to 2.3 liters. Custom Pauter rods and Ross pistons spin on a custom-built crankshaft of a secret identity. The reciprocating assembly was balanced and blueprinted. Key components were cryo-treated for enhanced durability.
The Rallye red EVO has minimal body tuning. A custom bumper frames the GReddy FMIC and a trick carbon-fiber hood saves weight and adds orifices for engine cooling. The wheels are the stock Enkeis from the factory but suspending them is a trick TEIN coil-over setup. TEIN Flex coil-overs, featuring the company's innovative EDFC that allows cockpit damper control on the fly, help the Mitsu resist lateral g-forces.
This car was originally supposed to appear in the May or June 2004 issue but the tuning regimen took some time and we wanted the car at 100 percent when it appeared here.
"The engine was tuned first for 20 psi (base boost), and then we ran 24 psi, 28 psi and 32 psi," relates Marinov. "The air/fuel ratio was kept very conservative at 10.9:1 and the tuning passes were made on C-16 race gas. On the first run, just to see how the turbo spooled, we did 411 whp at 10 psi letting off at 6000 rpm, just before the turbo really hit. At 32 psi we made a number of 700-plus-whp runs, topping out at 712. All the runs were turbo only.
"The EVO drives like a T88H Supra, just better because of the AWD," says Marinov. "It revs fast like a Hayabusa, even with the stroker kit and 8500-rpm redline. With the 150 nitrous shot, there is no lag."
The EVO's stock wheel and tire combo is hard to beat.
A Nitrous Express 150-shot setup is on call for spool-up enhancement.
We plan to do an update on this car if/when it runs at the track.