Daily Slideshow: Top Fuel's S2000 WTAC Contender

1. History Lesson

The Pro Class of the World Time Attack Challenge (WTAC) isn't called the World Time Attack Open. To compete against the best in the world you have to be invited, and only a few teams get the chance to represent their country. Cyber EVO from Japan took top honors the series' first two years, followed by close finishes from the USA's Sierra-Sierra Enterprises, but when Cyber Evo called it quits, it rekindled hope in the chests of tuners big and small.

Enter the confusingly named shop Stock Car World Rally Top Fuel, from Japan's Mie prefecture. Top Fuel's Mr. Morimoto began their effort in 2006 with an AP1 S2000 that was initially intended to act as a platform for testing their in-house F20C turbo kit. That first version of the car you see here employed the age-old formula of light weight and high horsepower, and had 600 hp to power the stripped-down, carbon-clad AP1's 2,000 lb curb weight. It was a success as far as it went, taking the rear wheel drive track record at the Tsukuba circuit for three years running.

>>Join the conversation about Top Fuel's S2000 WTAC Contender right here in S2ki.com.

2. Tunnel Training

But Top Fuel wanted to go further, they wanted to make a run at the WTAC. Based on fellow Japanese performance specialists Voltex Racing's commitment to testing their aero components in the wind tunnel, a partnership between the two companies was forged in 2011, with the WTAC as the ultimate goal. F1 veteran Voltex immediately went wide, with president Akihiro Nakajima working on sketches himself—from there the sketches were turned into widebody fenders, a carbon fiber front bumper with canards and splitter, aero side skirts, a rear diffuser, and a sufficiently huge rear wing. The new pieces were fit to the S2000, taken to the wind tunnel at Mie University for testing, and modifications were made to keep the drag low and downforce dialed in.

>>Join the conversation about Top Fuel's S2000 WTAC Contender right here in S2ki.com.

3. More Power

With the all-important aero tackled, attention was turned to wringing even more horses out of the FC20. Top Fuel re-sleeved the block with Darton International iron liners but left the bore stock, though they bumped the displacement up to 2,307cc through the use of a 97mm stroker crankshaft from BC Brian Crower. The engine went back together using Pauter connecting rods, CP pistons, and the stock cylinder head, yielding a 9.0:1 compression ratio. Top Fuel fit a larger HKS turbocharger, used in conjunction with their own exhaust manifold and an HKS intercooler coupled with the stock intake manifold. An HKS F-CON V Pro ECU replaces the stock Honda system, and together with the other modifications brought the hp rating up to 700.

>>Join the conversation about Top Fuel's S2000 WTAC Contender right here in S2ki.com.

4. Shoring Up

With 700 reliable hp, changes were needed to reliably transmit that power to the ground. The stock transmission was put aside and replaced with an HKS SR20 sequential trans, and mated to the engine via an OS Giken clutch and flywheel. From there a custom driveshaft takes the power back to a limited slip FD3S RX7 rear end, and finally to 11-inch wide Advan TCII 18-inch wheels wearing sticky Advan A050 racing tires—the new body kit allowing for an extra inch of rubber all around.

>>Join the conversation about Top Fuel's S2000 WTAC Contender right here in S2ki.com.

5. Show Time

With all of the modifications in place, the S2000 tipped the scales 662 lb heavier, the total weight now coming in at 2,662 lbs. Top Fuel's first shot at the WTAC with the new car was at Sydney Motorsports Park in 2012 with Nobuteru Taniguchi piloting the AP1. They fell short of their ultimate goal—Australia’s Nemo Racing EVO took the top trophy—but their lap time of 1:29.0520 earned them an encouraging fifth place. Adjustments to the chassis were made at Taniguchi's urging, making the car more stable, and the turbo was swapped out once again, this time for a GCG/Garrett GTX3582R unit. With the new turbo—and 32psi of boost—the FC20's power output went up to 765hp, while the transmission was also switched out sequential Holinger RD6S box. Changes in place, the team was back in Australia again trying to capture the WTAC Pro Class title, with Taniguchi managing a 1:28.8660 lap—but earning a second, now disappointing, fifth place. The team finally achieved the triumph they were looking for when Taniguchi set a new record for tuning cars at Fuji Speedway, his time of 1:40.195 beating the lap times of both the HKS CT230R and the Cyber EVO teams. The magic of the internet allows you to see that lap here. Sometimes it's true what they say, even when the goal is a single fast lap: racing is a marathon, not a sprint.

>>Join the conversation about Top Fuel's S2000 WTAC Contender right here in S2ki.com.