Footwork To Go Fast

As the new aerodynamics exerted more down force, reworking the suspension system became the next focus of the build. Endless’ Zeal Function adjustable dampers valved to Top Fuel’s custom specifications absorb the bumps while 26 kgf/mm and 28 kgf/mm (front and rear) linear-wound Eibach springs resist the pressure applied by the aerodynamics at speed. Ikeya Formula adjustable suspension arms replaced the factory pieces at each corner, offering the benefit of spherical bearings at pivot points and increased alignment flexibility for optimum suspension tuning.

Back In The Gym

While the new aerodynamics and refined suspension were being worked on, Morimoto went to work on the F20C engine that powered the Type-RR. Although it is uncommon for Japanese tuners to resleeve blocks, Top Fuel resleeved the F20C block with ductile iron units from Darton International. [pullquote]ALTHOUGH IT IS UNCOMMON FOR JAPANESE TUNERS TO RE-SLEEVE BLOCKS, TOP FUEL RE-SLEEVED THE F20C BLOCK WITH DUCTILE IRON UNITS FROM DARTON INTERNATIONAL[/pullquote] The block retained its 87mm bore but enlarged by 13 percent to 2,307cc thanks to a BC Brian Crower 97mm stroker crankshaft. Pauter Rods make the connection between the stroked crank and the 9.0:1 compression CP Pistons. The untouched cylinder head was examined and cleaned before rejoining the block.To take advantage of the increased displacement and stronger internals, the enlarged F20C engine was fitted with a larger turbocharger. Fed high enthalpy exhaust gasses from a Top Fuel exhaust manifold, an HKS turbocharger generated boost pressure that is channeled through custom piping to an HKS intercooler. Once chilled, the cooler, denser air charge makes its way to the factory intake manifold for distribution to the cylinders.

Power to the Ground

With each intake stroke, atomized Sunoco race fuel mixes with the incoming air charge and fills the cylinders. To regulate the fuel delivery and ignition timing, an HKS F-CON V Pro engine management system replaced the factory unit under the dash. Once the maps had been refined, the enlarged F20C generated 700 horsepower, an increase of 100 horsepower over the previous setup. The additional horsepower demanded improvements to the driveline to handle the power, make quick gear changes and endure the abuse of competition.

[pullquote]ONCE  THE MAPS HAD BEEN REFINED, THE ENLARGED F20C GENERATED 700 HORSEPOWER, AN INCREASE OF 100 HORSEPOWER OVER THE PREVIOUS SETUP[/pullquote]The S2000’s transmission and rear end do an admirable job at factory output levels, but stand no chance of survival when torque and horsepower figures nearly triple the stock numbers. Thus, an OS Giken clutch and flywheel transfer power from the crank to the input shaft of an HKS SR20 sequential transmission.The output shaft of the stout sequential box turns a custom propeller shaft linked to an FD3S RX7 rear end with limited slip differential (LSD). The LSD splits the power to the 18 by 11-inch Advan TCIII drive wheels mounted with Advan A050 race rubber. Compared to the previous setup, the wheels are an inch wider and the tires have increase in section width from 265mm to 295mm. This wheel and tire setup makes full use of the wide-body kit and increases the contact patch with the tarmac.