Circuit Titan XT

1999 Nissan Silvia S15

R151

Media library

9 photos · 1 films

Original Build Studies

6 images

Original Build Studies ↗

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Original Build Studies ↗

Ladies of WBS Gallery

1 image

Ladies of WBS ↗

Orbital Reel

1 film

Orbital Reel

Wave Photography

1 image

Wave Photography ↗

Platform Showcase

1 image

Platform Showcase ↗

Story

Circuit Titan XT treats the S15 like a late-’90s works car that never got signed off—wide track, hard aero, and cooling everywhere it matters. The carbon widebody isn’t just for silhouette: 1980mm front and 2000mm rear track width plant the chassis under sustained lateral load, while front louvering and ducted exits keep brakes and bay temps under control when the pace stays high.

Under the skin it’s the same idea: reinforce the platform, add tire, and let the aero do the heavy lifting past 250 km/h. An RB25DET with modern turbo hardware feeds the top end the S-chassis always wanted, and the whole package reads like a time attack program built to survive full sessions—not a one-lap hero.

Blueprint

The Whitepaper Room

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Collectible Poster

Collector's Edition

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Technical dossier

Fictional engineering concept

Platform

1999 Nissan Silvia S15

Powertrain concept

RB25DET rebuild with forged rotating assembly for sustained boost and heat
Modern ball-bearing turbo with efficient compressor map for high-speed circuit loads
Front-mount intercooler integrated with sealed bumper ducting
Water/meth injection for charge control and detonation margin on long pulls
Motorsport-grade engine management with fail-safes for pressure and temp

Aero package

Front arch-integrated forward-swept canards tied into bumper pressure zones
Full carbon vented hood with central chimney, twin NACA ducts, and longitudinal extractors
Deep rear diffuser with strakes and outer winglet fences
Dual-plane carbon rear wing on rigid adjustable uprights with gurney provisions
Vortex management details at the wing and rear deck to stabilize yaw at speed

Chassis & stance

1999 Nissan Silvia S15

Wheels & tires

Front: 18x11 ET+12 with 265/40R18 Toyo Proxes R888R
Rear: 18x12 ET+15 with 285/40R18 Toyo Proxes R888R
Flush-to-arch fitment with functional clearance for full compression and steering lock
Big brake package sized for sustained heat, with ducting routed through the front and quarter architecture

Fabrication notes

Custom widened suspension geometry with corrected scrub radius and bump steer management
Hub/knuckle and bearing upgrades to tolerate increased track width and tire load
Sealed ducting for brakes and bay extraction to prevent recirculation
Wing uprights tied into reinforced rear structure to keep angle-of-attack stable under load
Panel fit and fastener strategy designed for quick service between sessions