Vehicle performance begins at the core of chassis design, encompassing a variety of elements including frame stiffness, strength and rigidity. Often referred to as the fifth spring, a chassis does flex to some degree, just as the suspension travels up and down at each corner. The stiffer the chassis, the less change to suspension geometry, the better the handling.
Text by Richard Fong // Photos by Rob Shaw
Celebratory S2000 Roadster
Honda Motor Corporation released the S2000 in April of 1999 to commemorate its 50th anniversary. Following the naming conventions of Honda’s 1960s roadsters, the S2000 got its name from its 2,000cc F20C engine. Honda stated that its “High X-bone frame” improved the rigidity and safety of the chassis. The stiff chassis in conjunction with a 50/50 weight distribution resulted in a solid vehicle with remarkable handling.
Evasive Maneuvers
Taking an already well-handling vehicle to the next level is sometimes best left to a specialist. When it comes to the S2000, many think of the track-proven success that Evasive Motorsports has earned with the Honda roadster. From the time Evasive Motorsports opened its doors in 2002, its focus has been on balanced performance. This young shop demonstrated its tuning philosophy at various time attack events, eventually setting the street class record several times over with its S2000 R&D racecar. With hot shoe, Rob Walker, behind the wheel, the S2000 ran its best time of 1:51.77 at Buttonwillow Raceway in 2013. Although this record was recently broken, it’s quite the accomplishment for a naturally-aspirated vehicle on street tires.
It’s this sort of reputation that caught the attention of the owner of this 2005 AP2 S2000 track machine. As a circuit enthusiast, he currently owns and drives several dedicated track cars including a fully track prepped 2004 BMW M3 CSL and E92 M3. His garage also contains a Porsche GT3 and a GT3RS. Clearly, he is a fan of both horsepower and handling, and he has no reservations about driving them either.
Fresh Fabrication
This AP2 S2000 was delivered to Evasive Motorsports in April 2015 with a practically blank check and instructions to build it to be a track star. Drawing on its extensive experience tuning the S2000, the team at Evasive drew up a plan to reach this objective. The F22C engine was plucked from its home as work began on the chassis. Fabrication started with a V-mounted intercooler and radiator for optimum cooling. The radiator core support was modified to accommodate an HKS intercooler and Koyo radiator, while custom ducting directs airflow through the intercooler and out through ports cut out of the hood. A protective barrier in the form of a custom cage was then welded into the cockpit, shrouding the occupants within tubular steel. To further stiffen the chassis, the fabrication team stitch welded the shock towers. At the rear, the trunk floor was cut out before being fitted with custom chassis mounts for the Voltex Racing Type 7 carbon-fiber wing.
Aero for Speed and Traction
Once the welding was completed, the team turned its attention to the exterior of the chassis. A complete Voltex Racing S2000 aerodynamics package comprised of a front bumper, carbon-fiber lip spoiler and canards, side skirts, over fenders at each corner and a carbon-fiber rear diffuser user transformed the AP2 bodylines into a functional, downforce-producing machine. Inside the wheel wells, Evasive Motorsports-spec TEIN SRC adjustable coilovers drop the chassis over Volk Racing ZE40 wheels mounted with Yokohama ADVAN Neova AD08R rubber. Behind the spokes of the ZE40 wheels, AP Racing calipers with slotted rotors can be seen peeking through.
Built Up for Boost
As work progressed on the chassis, Evasive brought the F22C engine to the DSPORT machine shop to be overhauled. There, Magnus Ohlaker disassembled the engine and machined the block in preparation for a set of Darton MID sleeves. After fitting the sleeves to the block, Ohlaker bored the cylinders to the factory diameter of 87mm before filling them with a set of 11.0-to-1 compression CP Pistons. Carrillo connecting rods joined the pistons to the factory crankshaft , completing the shortblock assembly. While the block was being worked on, the cylinder head went to Tom Fujita at Port Flow Design to be ported and then reassembled with a complete Supertech valvetrain. Once the higher flowing cylinder head returned, Ohlaker reunited it with the block using a set of ARP head studs to provide the clamping force to keep the assembly secured together.
Blown with Alcohol
After dropping the strengthened engine back into the chassis, Evasive installed an HKS GT Supercharger system into the AP2. Centered on an HKS GTS7040 supercharger, a serpentine belt joins the crank pulley to a smaller drive pulley intended to increase boost pressure to approximately 14psi. The pressurized air flows from the compressor discharge port through hard pipe to the HKS intercooler to exchange heat with the atmosphere. Once chilled, the pressurized air distributes to the intake ports through the factory intake manifold. A quartet of Injector Dynamics ID1000 injectors sprays E85 fuel into the air charge as it fills the cylinders. To regulate the flow of fuel and the timing of the spark events, an AEM EMS V2 replaced the factory ECU under the dash. Once Evasive Motorsports’ resident tuner, Jason Reinholdt, finished calibrating the EMS, the S2000 spun the rollers of a Mustang Dynamometer to a peak output of 351 horsepower and 239 lb- torque to the wheels. Compared to the 215 horsepower typically produced by a stock S2000 on this dynamometer, this is a massive 63-percent increase in horsepower.
SEMA Stardom
Evasive Motorsports finished the build just before the 2015 SEMA Show in Las Vegas, Nevada. Although the S2000 hadn’t even been to the track yet, its performance pedigree and build quality earned it the anchor spot in the DSPORT Magazine SEMA booth. Now back at home in the garage with its European siblings, it’s time to go to the track to turn some laps. Its owner commented, “The S2000 is fun to drive and is the best platform to build on for the price. There’s no other car in the segment that can beat the performance it can deliver for the same price. I go to the track at least once a month and I’ll be comparing it to my M3s. At some point, I’ll add more aerodynamics to increase the pressure over the tires while bumping up the power even further to offset the aerodynamic drag.”
Honda engineered the S2000 to be a fun, well-balanced roadster in honor of its golden anniversary. Evasive Motorsports developed it further, setting records and applying the knowledge to its customer’s builds. Now this S2000 will take to the track, giving the M3s a run for the money.
SPEC SHEET
| VEHICLE | |
|---|---|
| Year / Make / Model: | 2005 Honda S2000 |
| Chassis Code: | AP2 |
| Competition Class: | Limited |
| Vehicle Weight: | 2,550 lbs |
| Weight Bias (F/R): | 50/50 |
| Redline RPM: | 8,400 RPM |
| Peak Boost: | 13psi |
| Fuel: | E85 |
| ENGINE | |
|---|---|
| Engine Code: | F22C1 |
| Displacement (cc): | 2,157cc |
| Bore & Stroke (mm): | 87mm x 90.7mm |
| Peak Horsepower (@ RPM): | 351 whp @ 8,400 RPM |
| Peak Torque (@ RPM): | 239 lb-ft @ 7,300 RPM |
| Dyno Type: | Mustang Dynamometer |
| Engine Builder: | Evasive Motorsports / DSPORT |
| Block Modifications: | Darton M.I.D. Iron Sleeves |
| Machine Work: | Magnus Ohlaker |
| Pistons/Compression Ratio: | CP Pistons, 87mm, 11.0:1 Compression |
| Connecting Rods / Crank: | Carrillo Forged Connecting Rods |
| Valves/Springs/Retainers: | Supertech Valves, Springs and Retainers |
| Cylinder Head Modifications: | Port Flow Cylinder Head Porting and Assembly |
| Head/Main Studs: | ARP Head Studs |
| Fuel Injectors: | Injector Dynamics ID1000 Injectors (x4) |
| Fuel Delivery System: | Deatschwerks 255lph Fuel Pumps (2x) |
| SARD Fuel Surge Tank | |
| Engine Management System: | AEM EMS Series 2 |
| Engine Management Tuner: | Jason Reinholdt @ Evasive Motorsports |
| Ignition System: | Ignition Projects Coils |
| Spark Plugs: | NGK |
| Exhaust Manifold: | J’s Racing Stainless Steel 4-2-1 Manifold |
| Exhaust System / Downpipe: | Evasive Motorsports Custom Exhaust |
| Blow-Off Valve: | HKS |
| Intercooler: | HKS Intercooler w/Custom V-Mount |
| Oil System: | GReddy GREX Oil Filter Relocation Kit |
| Cooling System: | Koyo Rad w/Custom V-Mount |
| Performance Electronics: | AEM Wideband UEGO Gauge |
| SUPERCHARGER | |
|---|---|
| Supercharger: | HKS GT Supercharger |
| Frame: | GTS7040 |
| Pulley: | 110mm, 8 Ribs |
| Compressor Wheel Specs: | 82mm Major, 61mm Inducer |
| Compressor Housing: | 61mm Inducer Port, 44mm Exducer Port |
| CHASSIS/DRIVELINE | |
|---|---|
| Springs, F&R (Make & Rate): | TEIN 16kgf/mm |
| Shocks, F&R (Make & Rate): | TEIN SRC Coilovers, Evasive Spec |
| Additional Suspension Components: | Cusco Spherical Bearings, Eibach Sway Bars (F&R) |
| J’s Racing Roll Center Adjusters, Fender Reinforcement | |
| Spoon Sports Rigid Collars, Steering Rigid Collars, | |
| & Gusset Plates | |
| Clutch / Flywheel: | Exedy Hyper Single Clutch |
| Differential(s) (Make & Type): | OS Giken Super Lock LSD |
| Evasive Motorsports Differential Housing | |
| Wheels (Make, Size & Offset): | Volk Racing ZE40 18×10-inch +35 (F&R) |
| Tires (Make & Size): | Yokohama AD08R 285/35R18 (F&R) |
| Brake Calipers (F&R): | AP Racing Big Brake Kit (F) |
| Brake Rotors (Diameter, F&R): | AP Racing (F), J’s Racing Large Rotor (R) |
| Brake Pads (Front & Rear): | Project Mu Club Racer Brake Pads (F&R) |
| Brake Lines: | AP Racing Stainless-steel Braided Lines |
| INTERIOR | |
|---|---|
| Roll Bar / Cage: | Evasive Motorsports Custom Cage |
| Seats: | Recaro Pro Racer Hans SPG (Driver) |
| Recaro SPG | |
| Harnesses: | Schroth 6-point Harnesses |
| Steering Wheel / Quick Release: | OMP Steering Wheel |
| Works Bell Quick Release Hub | |
| Gauges: | AiM Sports MXS Dash Logger |
| EXTERIOR | |
|---|---|
| Front Bumper/Lip Spoiler: | Voltex Racing |
| Fenders, Diffuser: | Voltex Racing |
| Hood: | Evasive Motorsports Custom Ducted Hood |
| Side Skirts, Rear Over Fenders: | Voltex Racing |
| Rear Bumper: | Factory AP1 Rear Bumper |
| Trunk Lid: | K1 Lab |
| Spoiler / Wing: | Voltex Racing Type 7, Custom Chassis Mount |
| Doors: | J’s Racing CFRP |
| Mirrors: | Craftsquare Mirrors |
| Paint: | Signature Autobody Custom Paint |