The JTS engine (Jet Thrust Stoichiometric) is a

gasoline direct injection Gasoline direct injection (GDI), also known as petrol direct injection (PDI), is a fuel injection system for internal combustion engines that run on gasoline (petrol) which injects fuel directly into the combustion chamber. This is distinct f ...

engine produced by

Alfa Romeo Alfa Romeo Automobiles S.p.A. () is an Italian carmaker known for its sports-oriented vehicles, strong auto racing heritage, and iconic design. Headquartered in Turin, Italy, it is a subsidiary of Stellantis Europe and one of 14 brands of mu ...

. It exists in two forms,

straight-4 A straight-four engine (also referred to as an inline-four engine) is a four-cylinder piston engine where cylinders are arranged in a line along a common crankshaft. The majority of automotive four-cylinder engines use a straight-four layout ( ...

and V6, and was introduced into the Alfa lineup in 2002.

Four-cylinder

2.0

The JTS engine debuted in 2002 in the

Alfa Romeo 156 The Alfa Romeo 156 (Type 932) is a compact executive car produced by the Italian automobile manufacturer Alfa Romeo. It was introduced at the Frankfurt Motor Show#1997, 1997 Frankfurt Motor Show as the replacement for the Alfa Romeo 155. The 156 ...

. The engine was based on the 2.0

Twin Spark Alfa Romeo Twin Spark (TS) technology was used for the first time in the Alfa Romeo Grand Prix car in 1914. In the early 1960s it was used in their race cars ( GTA, TZ) to enable it to achieve a higher power output from its engines. And in the e ...

(itself a variant of the Pratola Serra engine family), replacing Twin Spark with direct injection, dubbed "Jet Thrust Stoichiometric". This improved power from to , but more importantly, torque climbed from to . In 2003, this engine was introduced to the GTV/Spider coupé and roadster and it was fitted to the GT from launch. In spite of its benefits to power, torque and economy, the JTS was not used in the smaller 147 or the larger 166, and much less in other models from the

Fiat Group Stellantis Europe S.p.A. (formerly Fiat Group Automobiles S.p.A. and FCA Italy S.p.A.), is the Italian subsidiary of the multinational automaker Stellantis, dedicated to the production and selling of passenger cars and light commercial vehicles ...

. This was allegedly because the JTS engine cost a lot more to produce than the Twin Spark. *Displacement: *Power: @ 6400 rpm *Torque: @ 3250 rpm Applications: *2002-2005

*2003-2004

Alfa Romeo GTV & Spider The Alfa Romeo GTV and the Alfa Romeo Spider (Type 916) are sports cars produced by the Italian automobile manufacturer Alfa Romeo from 1993 to 2004. The GTV is a 2+2 coupé, while the Spider is a two-seater roadster. Production totaled 38,891 ...

*2004-2010

Alfa Romeo GT The Alfa Romeo GT (Type 937) is a sporting coupé that was produced by the Italian automaker Alfa Romeo between 2003 and 2010. It was the last production Alfa Romeo designed by Bertone. The GT was introduced in March 2003 at the Geneva Motor Show ...

1.9

It was only in 2005, with the arrival of the 159, that more variants of the JTS were produced. The 2.0 JTS gave way to a 1.9 L variant with and a 2.2 L version with . The 1.9 JTS and 2.2 JTS form part of a new engine family and are completely different from the 2.0 JTS. Both 1.9 L and 2.2 L have chain driven camshafts and

variable valve timing Variable valve timing (VVT) is the process of altering the timing of a Poppet valve, valve lift event in an internal combustion engine, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combina ...

on both inlet and exhaust camshafts. Both 1.9 and 2.2 JTS engine blocks were supplied by GM to the Fiat group and belong to the GM Ecotec engine family. Both models are mapped to either a six-speed manual gearbox plus a reverse gear, or a Formula One inspired sequential gearbox also having six gears and reverse. *Displacement: *Power: @ 6500 rpm *Torque: @ 4500 rpm Applications: *2005–2011

Alfa Romeo 159 The Alfa Romeo 159 (Type 939) is a car built by Italian marque Alfa Romeo between 2004 and 2011. It is a large family car in the compact-executive market segment with four-door saloon and five-door estate variants. Introduced at the 2005 ...

2.2

With the arrival of 159, a 2.2 JTS was also introduced. The engine block is sourced from GM ( Ecotec L61). *Displacement: *Power: @ 6500 rpm *Torque: @ 4500 rpm *Compression Ratio: 11:3:1 Applications: *2005–2010

*2005–2010

Alfa Romeo Brera The Alfa Romeo Brera and the Alfa Romeo Spider (Type 939) are mid-size sports cars using the GM/Fiat Premium platform, manufactured by Pininfarina and marketed by Alfa Romeo as a 2+2 (car body style), 2+2 coupé and Roadster (automobile), roadste ...

*2006–2010

Alfa Romeo Spider The Alfa Romeo Spider (105/115 series) is a two-seater, front-engined, rear-drive roadster (automobile), roadster manufactured and marketed by Alfa Romeo from 1966 to 1994 in four distinct generations, or "series", each with modifications rangin ...

Six-cylinder

3.2

The ''JTS'' direct injection system was first used in a V6 engine in 2005 with the introduction of the Alfa 159 and Brera. This is not related to the

Alfa Romeo V6 engine The Alfa Romeo V6 engine (also called the Busso V6) is a 60° V6 engine made by Alfa Romeo from 1979 to 2005. It was developed in the early 1970s by Giuseppe Busso, and first used on the Alfa 6 with a displacement of and a SOHC 12-valve cylin ...

, but is instead a derivation of the

GM High Feature engine The GM High Feature engine (also known as the HFV6, and including the 3600 LY7 and derivative LP1) is a family of modern DOHC V6 engines produced by General Motors. The series was introduced in 2004 with the Cadillac CTS and the Holden Commodore ...

; built in Australia by GM Holden. While it retains the High Feature engine's bore x stroke and chain driven camshafts, it is modified by Alfa for their performance,

fuel economy Fuel efficiency (or fuel economy) is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may v ...

and sound characteristics. These modifications include: "TwinPhaser" variable valve timing (cam-phasing on both inlet and exhaust cams, thus the name),

and a higher

compression ratio The compression ratio is the ratio between the maximum and minimum volume during the compression stage of the power cycle in a piston or Wankel engine. A fundamental specification for such engines, it can be measured in two different ways. Th ...

of 11.25:1. It also operates with a lean burn system up to about 1500 rpm, as on many other engines from the company and is capable of generating , a number matching the larger ''LY7'' 3.6 L variant used by GM. Alfa Romeo stopped using the V6 JTS engine in 2010. *Displacement: *Power: at 6200 rpm *Torque: at 3800 rpm Applications: *2004

Alfa Romeo Visconti The Alfa Romeo Visconti is a concept car made by the Italian car manufacturer Alfa Romeo, designed by Giorgetto Giugiaro. The car was seen for the first time at the Geneva Motor Show in 2004. The car is a four-door fastback coupé/ sedan and is alm ...

(concept car) *2004–2011

*2005–2010

*2006–2010

References

{{Alfa Romeo Alfa Romeo engines General Motors engines Straight-four engines V6 engines Gasoline engines by model Automotive engine technologies