January 15, 2008

We have had some unique cars here at Imagine, but the Saker GT is more than unique. For those who may not know exactly what a Saker GT is I have one way of putting it into perspective for you: 1700lb. street-legal race car. This mid-engined monster is far from civilized and carries only the minimum requirements of a street car. No power windows, no heated seats, just a tube frame, four wheels, and a turbo boxer engine.

The Saker, available in both closed cockpit & open air configurations, is built around Subaru’s superbly engineered, race proven EJ257 single-turbo boxer-4 engine. This dual overhead cam, semi-closed deck four is designed for full range power delivery. Lengthy intake runners and a long stroke provide ample torque for low end power and throttle response. High RPM power is provided by a single VF39 turbo and an efficient plumbing system. Using a top-mount intercooler, pressurized air travels a short path (about two feet) from the compressor housing, through the intercooler, and into the throttle body. This optimizes responsiveness and provides a compact, balanced power plant perfect for a race car. Backing the design of this motor is a huge after market, catering to any high horsepower needs. For example Cosworth, a major name in racing and performance engines, has an entire line of internal components, cylinder heads, and blocks for these motors.

The Saker’s chassis consists of a square tubing frame making creative use of triangulation and space. However sheet metal and fiberglass air dams cover most everything when on the road. Suspension is comprised of double “A” arm style aluminum control arms following the “short-arm, long-arm” design providing camber gain under hard cornering loads. By having a shorter length control arm on top at a slightly different angle from the lower control arm, negative camber is increased under cornering loads.

This particular Saker GT pictured above less nose and tail body work came to us under unusual circumstances. Our friends over at Rosso Motors brought the car to us one morning on a trailer. The owner of the car, who races often, complained of a serious lack of power. Particularly at high RPM. Having had quite a bit of experience with these motors and other Subaru EJ-series engines, I was naturally drawn to the car. Steven D and myself set the car up on the dyno first, which was a task in itself (note the ground clearance in comparison to our dyno ramps). On the dyno the car made over 400hp to the wheels but we determined that boost was erratic and trailed off at high rpm. A little digging around and we discovered the factory VF39 turbo had a substantial amount of shaft play, which led to the compressor wheel making contact with the inside of the housing, wearing down the wheel’s blades. Unfortunately we only got to diagnose the problem. The guys at Rosso Motors returned and took the car back to their shop to replace the turbo themselves, though it is a very simple installation.

Much more can be said about the Saker Sportscars but perhaps the most intriguing thing about these cars is the fact that they are designed to be an affordable race car. A turn-key GT bought directly from Saker Europe costs 43,950 Euro.