2006 Saab 9-3 Aero

The last time Saab begged parent GM for an engine with enough cylinders to compete in the U.S., it was thrown an odd 3.0-liter, 54-degree iron-block V-6 and a tiny budget with which to Saabify it. A turbo on the front bank pressurized the whole engine to just 3.9 psi (the internal structure couldn't tolerate any more), so output was constrained to a ho-hum 200 horsepower, and sales ended in 2003. This new 60-degree turbo V-6 is custom-tailored for Saab.

The engine shares its chain-driven DOHC architecture and variable intake-valve timing with the "high-feature" V-6 currently powering Cadillacs and other upscale GM vehicles. The turbo is Saab's alone, but some features required to meet the demands of turbocharging, like oil-cooled pistons, have been applied across the other brands. Stronger forged connecting rods and high-strength aluminum cylinder heads fortify the combustion chamber sufficiently to run almost nine pounds of boost with a compression ratio of 9.5:1.

2006 Saab 9-3 Aero
Base price	$35,100 (est)
Vehicle layout	Front engine, FWD, 4-door, 5-pass sedan
Engine	2.8L/247 hp/258 lb-ft turbo-charged DOHC 24-valve V-6
Transmission	6-speed man; 6-speed auto
Curb weight	3450 lbs (mfr)
Wheelbase	105.3 in
Length x Width x Height	182.5 x 69.0 x 56.8 in
0-60 mph	6.0-7.0 sec (MT est)
EPA city/hwy fuel econ	Not yet rated
On sale in U.S.	September 2005

The water-cooled Mitsubishi TDO4-15TK turbocharger is a twin-scroll design, meaning two separate chambers channel exhaust from each cylinder bank directly onto the turbine wheel. By doing this, the individual exhaust pulses in each header help push the turbine, boosting performance and reducing lag. Collecting the exhaust before it reaches the turbo allows these pulses to cancel out. Saab investigated an even wilder approach to reducing boost lag: turning the cylinder heads around so the exhaust came out in the valley and fed sequential twin-turbos, but intense heat was melting paint on the hood.

Saab claims the 9-3 Aero V-6 is its quickest car ever, so we expect the six-speed manual version to just edge ahead of the Viggen and 9-2x Aero, hitting 60 mph in six seconds flat and the quarter in the mid-14s with the Aisin six-speed automatic version running about a second off that pace. This six never feels as peaky and high-strung as Saab's turbo fours often do, and torque steer, with the wheel pointed straight ahead, is unnoticeable on smooth roads. Ample thrust is available at all speeds, so passing maneuvers can be accomplished without shifting. This is a good thing, because the six-speed manual box feels notchy, particularly when shifting from first to second or fifth to sixth. The automatic seems well matched to the engine and offers a fully manual mode with steering-wheel shifting.

Tweaks were made to the suspension bushings and springs, primarily to account for the V-6's 180 pounds of extra weight. Tighter steering and larger anti-roll bars improve the new Aero's road manners and general responsiveness while retaining a supple ride quality. It won't pass for a BMW (we've never driven a front-drive car that could), but we expect the new 9-3 Aero to stand tall against other high-performing front-drivers. Sedan sales begin this September priced just above $35,000, with wagon and convertible versions following in December.