While there are a number of different roads Saleen’s engine designers could have traveled down to achieve those high-altitude horsepower and torque figures, for this second edition of the Saleen S7 Twin Turbo they decided to think beyond atmospheric. And because this is Saleen, they added a double twist to a tried and true racing technique for boosting power and torque: twin turbos.
Aerodynamics has also come under scrutiny for 2005. Unless you place the new Saleen S7 Twin Turbo next to one of the original 2002 models, you probably won’t notice that the 2005 version has a different diffuser/rear spoiler package and reshaped front fenders to enhance the S7s already sleek, swoopy and aerodynamic contours. To complement the Twin Turbo’s enhanced straight-line performance envelope the S7 chassis has also undergone a fair amount of tweaking. Virtually every suspension pickup point has been changed, and the suspension geometry has been modified for less squat and dive during acceleration and braking.
Designed by Saleen engineers, the S7′s engine and drivetrain incorporate the latest in modern racing technology. The new all-aluminum V8 engine casting was engineered and tooled by Saleen to displace seven liters. Redline is 6500 rpm. Space age materials and engineering are used throughout, including stainless steel valves, titanium retainers, beryllium exhaust valve seats, an aluminum throttle body, Saleendesigned aluminum CNC-machined cylinder heads and stainless steel exhaust system. An exclusive Saleen-designed Front Engine Accessory Drive (FEAD) system results in an extremely compact engine, allowing for better packaging and overall weight distribution. The V8 incorporates a unique Saleen-designed side-mounted water pump, a belt-driven camshaft drive and a Saleen-engineered dry sump oil delivery system. The engine’s mid-chassis placement optimizes weight distribution and center of gravity, making room for an unusually tall engine that allows for a very efficient induction system. Air enters a roof intake, passes through a 90-mm mass air meter and feeds into a carbon fiber plenum. From the plenum the air is routed to the twin ball bearing turbos, is pressurized to 5.5 psi max and then passes through an oval-bore throttle body into an aluminum intake manifold with eight individual runners.
To feed juice to this setup, the injection system includes dual electric fuel pumps and high-capacity, return-less, 52 lb/hr fuel injectors. Neatly engineered and integrated into the S7’s stainless steel, dual, high-flow exhaust system are two, twin-ball-bearing, water-cooled Saleen-Garrett turbos, featuring 44-mm wastegates. The four exhaust pipes from each bank of cylinders merge into a race-car-like high-efficiency collector. In addition, the exhaust incorporates dual catalysts per cylinder bank, EGR and those aforementioned twin wastegates. And because Saleen believes in power and clean air, the emission control system features dual, heated oxygen sensors per cylinder bank and a high-volume evaporative emission system along with those four catalysts. Oh, and for good measure and clean air, the system is OBD-II compliant.
And if you need any more proof of how Saleen engineers sweat the details, the stroke of the already short-stroke shifter has been furthered shortened for improved shifting feel. Say that five times fast, once for each gear change.