Originally Posted by Wikipedia

On engines produced before 2007, spark was produced via 2 coils in a cassette that bolted to the top of the valve cover which contained the boots for each spark plug on the bottom of it, eliminating the need for wires. In 2007 the L61 was upgraded with a new Gen II engine block, cylinder head improvements, new camshaft design, E37 engine control module, 58X crankshaft reluctor ring, digital crank and cam sensors, individual coil-on-plug ignition, vented starter solenoid, new MAP sensor, new intake manifold seals, new oil filter element, a 32-bit computer, and improved emissions performance.

Originally Posted by GMInsideNews.Com

2007 Ecotec 2.2L I4 ( L61 )

ECOTEC 2.2L I4 (L61) CAR AND TRUCK ENGINE
2007 Model Year Summary

• Gen II Engine Block
• Cylinder Head Improvements
• New Camshaft Design
• E37 Engine Control Module
• 58X Crankshaft Reluctor Ring
• Digital Crank and Cam Sensors
• Individual Coil-on-Plug Ignition
• Vented Starter Solenoid
• New MAP Sensor
• New Intake Manifold Seals
• New Oil Filter Element
• Improved Emissions Performance

Originally Posted by ECOTECFORUM.COM

Full Description of New and Updated Features

Gen II Engine Block
The Ecotec 2.2L starts with a refined engine block, introduced for 2006 with the Ecotec 2.4L VVT (RPO LE5). The Gen II block was developed with data acquired in racing programs and the latest math-based tools. Both the bore walls and bulkheads, or the structural elements that support the crank bearings, have been strengthened, with only a minimal weight increase (approximately 2.5 pounds). The coolant jackets have been expanded, allowing more precise bore roundness and improving the block’s ability to dissipate heat. Coolant capacity increases approximately .5 liter.

The cylinder block is the engine’s foundation, and crucial to its durability, output and smooth operation. For GM, the common Gen II Ecotec block increases assembly efficiency. For the customer, the result is more efficient cooling, more strength to accommodate additional power, as in the new Ecotec 2.0L direct-injection Turbo (RPO LNF) and better noise, vibration and harshness control.

Cylinder Head Improvements
The Ecotec 2.2L also benefits from cylinder head refinements introduced on the 2.4L VVT. The exhaust ports have been enlarged slightly with machining improvements to expel exhaust gas more efficiently. Both engines share a common nodular cast iron exhaust manifold, chosen for its durability and sound-deadening properties. The improvements to the cylinder head increase Ecotec 2.2L horsepower slightly in most applications (see specs).

New Camshaft Design
The exhaust cam has been re-profiled to take advantage of refinements in the cylinder head. Maximum exhaust valve lift does not change, but duration increases slightly. The cams also feature a new 4X timing reluctor, replacing timing sensors previously contained in the ignition-coil cassette (see Individual Coil-On-Plug ignition, below). The powder metal reluctor wheel is pressed onto the camshaft at the rear. The 4X reluctor improves ignition timing accuracy and maintains precise consistency over the life of the engine.

Individual Coil-On-Plug Ignition
The Ecotec 2.2.L is equipped with individual coil-on-plug ignition, or four separate coils. Each coil sits directly over a spark plug, with no wire in between. Previous Ecotec 2.2Ls had two coils in a single cassette, with each coil shared by two spark plugs. Individual coil-on-plug delivers maximum voltage and the most consistent spark density. The 2.2L’s cast aluminum cam cover has been redesigned to accommodate the four coils.

E37 Engine Control Module
An advanced controller manages the multitude of operations that occur within the Ecotec 2.2L every split second. The E37 is the S-3 Controller within GM’s new family of three engine control modules (ECM) that will direct nearly all the engines in Powertrain’s line-up. The E37 is the high-value variant, yet it’s anything but basic. It features 32-bit processing, compared to the conventional 16-bit processing in previous Ecotec 2.2Ls. It operates at 59 MHz, with 32 megabytes of flash memory, 128 kilobytes of RAM and a high-speed CAN bus, and it synchronizes several dozen functions, from spark timing to cruise control operation to traction control calculations. The E37 works roughly 50 times faster than the first computers used on internal combustion engines in the late 1970s, which managed five or six functions.

Originally Posted by 007CobaltLS

So I should definitely be safe to run the ZZP stage 2 SC setup on my stock internals as long as my tune is done well? Want to make sure because next summer I'm finally going FI with my car after 4 years of slowly building up to it. 225WHP is my goal, but if more is made off of it, I'll be happy. I say 225 because as you can see by my sig, I'm auto. I couldn't remember how much power everyone said these engines can take stock before parts need replacing.

Originally Posted by rcorona8

2007 lsj sc is gen 1 block?

Originally Posted by Bumsnee

Will a gen 2 head off of a 2007 l61 work on a gen 1 block out of a 03 (I think) cavalier?

Originally Posted by Slowbalt2000

yes as long as its going into a car that uses a gen2 head.