Hankook Tire / JIC Magic S15 Sets New Time-Attack Record
Racing against the clock. It's the basic premise for time-attack competition. It's also the ultimate challenge of a racecar versus a road course. How much speed can be obtained on the straight, how late can the driver be on the brakes and how deep in the turn can one go while staying on the track. A time-attack course challenges all performance aspects of a vehicle from engine to gearing to suspension to braking and traction. If a car is weak in any one area it will not be able to hold up against the competition.
Coming to America
JIC Magic USA decided it wanted to increase its company's profile through participating in various time-attack and drifting events in the United States. While campaigning a single car is enough to quickly drain a marketing budget, campaigning two separate vehicles can easily eat up twice the budget while delivering half the results. JIC Magic USA and JIC Japan concluded that a single vehicle capable of competing in both arenas would ultimately produce the best results. To reduce the development time for the racecar, JIC Japan offered JIC Magic USA its Nissan Silvia S15 that was originally build to compete in various D1 drift events in Japan. As one of Japan's most popular performance platforms, JIC Magic was confident that they could find all of the parts and support needed to build a winner.
Head Start
The development work done on the S15 by JIC Magic Japan provided a solid foundation and great head start for JIC Magic USA. The chassis of the S15 had already been stripped of non-essential items and stitch-welded for increased unibody rigidity. The S15's chassis rigidity was further improved with the addition of a roll cage fabricated by M-1 Fabrication. This rigid chassis allows the S15's suspension to operate more efficiently and with greater predictability.
While competing in Japan, the Hankook Tire / JIC Magic S15 had the opportunity to put in some serious track time. This track time facilitated precise tuning of the JIC FLT-A2 coil-over suspension system. The track time also allowed the JIC Control Arms to be adjusted for optimum alignment. While these setting would eventually be tweaked as other changes were made to the vehicle, they did provide a very good baseline.
Maximizing Contact Patch
In road racing, contact patch is one of the most critical factors in determining a vehicle's performance. A vehicle's suspension should position, align, and control the tire to create the maximum size contact patch at all four corners of the vehicle. Furthermore, the suspension needs to accomplish this goal under every conceivable condition. These conditions include wide-open throttle acceleration, hard braking, low-speed cornering and high-speed cornering. While the JIC coil-over suspension and suspension arms work to provide the largest possible contact patch, it's the four Hankook Ventus Z214 C71 DOT tires that are engineered to maximize the quality of that contact patch. The four 275/35ZR18 tires feature upon a special sidewall and belt construction along with a sticky compound to maximize the traction between the vehicle and the road.
Stop and Go
Getting around a road course in record time requires that a vehicle is capable of going as fast as possible at every section of the track. Of course, straightaway speeds are primarily a factor of a vehicles power-to-weight ratio. The higher the power of the vehicle or the lower the weight, the faster the straightaway speeds. Since a time-attack vehicle is attacking the road course for up to 20 minutes at a time, a reliable and capable engine combination is a requirement. To this end, JIC Magic sought the assistance of TOMEI to supply a Genesis Phase 2 complete engine teamed to a custom Garrett turbocharger.
The TOMEI Genesis Phase 2 SR22 engine is a completely built "stroker" solution. A factory Nissan SR20 block is bored a minimum of .5mm-over and fitted with a set of TOMEI forged-aluminum pistons. These specially-designed 8.5-to-1 TOMEI pistons are engineered for street, competition and endurance type applications. The TOMEI pistons incorporate a special cooling channel that is claimed to keep the piston head temperatures down. The pistons also rely upon titanium coated rings for increased high-temperature durability. The pistons are joined to a 91mm, fully counterweighted TOMEI forged-steel crankshaft by way of TOMEI H-beam forged-steel connecting rods. This 86.5mm x 91.0mm assembly delivers a displacement of 2,138cc. Up top, the cylinder head has received attention from both TOMEI and Port Flow Design (not part of the standard Phase 2 package). The head was ported by Port Flow Design before being fitted with oversized Port Flow Design intake valves, TOMEI dual springs, TOMEI retainers and TOMEI 270-degree Poncam camshafts. A set of TOMEI head studs squeeze a TOMEI metal head gasket between the top and bottom of the engine.
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