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Discussion Starter #1
I have recently talked to the service advisor at the dealership where I purchased my car and a service tech at the local Cadillac dealership. They both claim that the V-6 in the LTZ is the same as the CTS. The difference is the CTS has 304hp while the LTZ only has 252hp which according to them is simply a difference in the programming of the on-board computer and a different air intake. This can be changed by installing a K&N cold air intake and a performance chip. Has anyone seen a company carry any perfomance parts for the new Malibu yet?
 

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I believe your service department is mistaken. Yes the Malibu 3.6 has the same engine as the CTS but it is 263 HP base model. The 304 HP engine is the Direct Injection upgrade which I believe is more than programming and intake (it is a completely different engine). I have heard as well that the difference of 11 HP in the base CTS vs. Malibu is simply programming.
 

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Discussion Starter #3
Same engine different intake.
 

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It may be the same "engine" but there is a lot more involved then a different intake...

http://media.gm.com/eur/cad/en/news/pk/pk_07.11.02_CTS/6_CTS_Performance.doc

Direct-Injection technology
The 3.6L Direct Injection engine is the premium engine option for the 2008 CTS. This technology on the 3.6L VVT engine contributes greatly to a 15-percent increase in horsepower; 8-percent increase in torque, and 3-percent improvement in fuel consumption. Additionally, the application of direct injection reduces cold-start hydrocarbon emissions by 25 percent and it is designed to operate with regular unleaded gasoline. The engine also helps the CTS achieve zero to 100 km/h performance of 6.3 seconds and a top speed of 249 km/h (electronically limited).

Gasoline direct injection differs from the fuel delivery process of a conventional fuel injected engine by delivering fuel directly into the combustion chamber, where it is mixed with air drawn in the chamber; the conventional design mixes the air and fuel prior to delivery into the combustion chamber. The advantage is improved fuel control and a more complete burn, which generally requires less fuel than a conventionally injected engine of the same size and configuration.

With the 3.6L direct injection engine, fuel is introduced directly to the cylinder during the intake stroke. As the piston approaches top-dead center, the mixture is ignited by the spark plug. The fuel injectors are located beneath the intake ports, as the intake ports only transfer air. Direct injection also permits a slightly higher compression ratio than if the fuel were delivered with conventional fuel injection. The result is better fuel consumption at part and full throttle. The engine uses conventional spark plugs similar to other high-feature V-6 engines.

A high-pressure, returnless fuel system is employed. It features a high-strength stainless steel fuel line that feeds a variable-pressure fuel rail. Direct injection requires higher fuel pressure than conventional fuel injected engines and an engine-driven high-pressure fuel pump is used to supply up to 1,740 psi (120 bar) of pressure. The system regulates lower fuel pressure at idle – approximately 508 psi (35 bar) and higher pressure at wide-open throttle. The exhaust cam-driven high-pressure pump works in conjunction with a conventional fuel tank-mounted supply pump.

Direct injection’s fuel delivery enables very efficient combustion to help reduce emissions, particularly on cold starts – the time when most tailpipe emissions are typically created. Also, direct injection permits a higher compression ratio – 11.3:1 in the case of the 3.6L – which has a positive influence on fuel economy.

3.6L Direct Injection VVT
The 3.6L Direct Injection VVT engine is based on a sophisticated 60-degree dual overhead cam (DOHC) V-6 design. It is the latest member of a growing family of V-6 engines developed for applications around the world, drawing on the best practices and creative expertise of technical experts in Australia, Germany, North America and Sweden.

Features found on the 3.6-liter VVT DI include:
• Aluminum engine block and cylinder heads
• Dual overhead cams with four valves per cylinder and silent chain primary drive
• High-pressure, engine-driven fuel pump
• Advanced multi-outlet fuel injectors developed to withstand high pressure and heat
• Stainless steel, variable pressure fuel rail
• Four-cam phasing (VVT – see description below)
• 11.3:1 compression ratio
• Aluminum pistons with floating wrist pins and oil squirters
• Polymer coated piston skirts
• Forged steel crankshaft
• Sinter-forged connecting rods
• Structural cast-aluminum oil pan with steel baffles
• Electronic throttle control with integrated cruise control
• Coil-on-plug ignition
• Advanced direct injection capable engine control module (ECM)
• Optimized exhaust manifolds with close-coupled catalytic converters
• Fully isolated composite camshaft covers
• Outstanding noise, vibration and harshness control
• Maximum durability with minimum maintenance
• Common manufacturing practices for efficiency and exceptional quality

Four-cam phasing
The 3.6L Direct Injection VVT employs four-cam phasing to change the timing of valve operation as operating conditions such as rpm and engine load vary. The result is linear delivery of torque, with near-peak levels over a broad rpm range, and high specific output (maximum horsepower per liter of displacement) without sacrificing overall engine response and driveability. When combined, direct injection and cam phasing technologies result in an unmatched combination of power, efficiency and low emissions in gasoline V-6 engines.

Cam phasing pays big dividends in reducing exhaust emissions by optimizing exhaust valve overlap and eliminating the need for a separate exhaust gas recirculation (EGR) system.

By closing the exhaust valves late at appropriate times, the cam phasers allow the engine to draw the desired amount of exhaust gas back into the combustion chamber, reducing unburned hydrocarbon emissions. The return of exhaust gases also decreases peak temperatures, which contributes to the reduction of oxides of nitrogen (NOx) emissions. In tandem with the dramatic 25-percent reduction in cold-start hydrocarbon emissions brought on by direct injection, the 3.6L Direct Injection VVT V-6 surpasses all emissions mandates, and does so without complex, weight-increasing emissions control systems such as EGR and air injection reaction (AIR).
 

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Discussion Starter #5 (Edited)
Interesting. Very informative website you quoted. Thanks for the clarification. Maybe the dealerships need to be informed a little more on their products. It would be nice to get over 300hp out of the car though.
 

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Interesting. Very informative website you quoted. Thanks for the clarification. Maybe the dealerships need to be informed a little more on their products. It would be nice to get over 300hp out of the car though.
No problem! 300hp and better fuel mileage sounds good to me too! But with everything there comes a cost... It does look promising though as one way for GM to get closer to meeting the CAFE regulations and not compromise performance.
 

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As said by another member in another thread; I too am skeptical about these inexpensive performance/fuel efficient modifications. If it were that cheap and that easy, the likes of GM wouldn't need to spend Billions of $$s to figure out how to get their entire fleet at 30MPG or better by 2015.

If you buy one and truly see the benefit please let us know, we'd love to hear the results!
 

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Discussion Starter #9
I am skeptical about the controller and how it creates better fuel economy. I am interested in the horsepower gain though. Just wondering what the general though was on these things. They work on trucks for power.
 

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This looks like the inline resistor part that was discussed on our other thread. If it is, the so-called "Chip" is just a simple resistor (a 5¢ part) that tricks the air sensor into thinking the temperature is offset so the computer tries to compensate by offsetting your fuel/air ratio. The offset might give a minor fuel savings under some conditions, but likely could cause more problems under altering conditions that are more common. Looks to be just another "Too good to be true story".

A true "Chip" modification requires that you replace an actual memory IC or processor IC deep in the computer board assembly. Some vehicle systems will let you reprogram the "Chip" without a physical hardware change if you happen to have access to the special reprogramming tool, the special GM access codes, and new software code from an expert performance hacker.

DrD
 

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Discussion Starter #11
Some vehicle systems will let you reprogram the "Chip" without a physical hardware change if you happen to have access to the special reprogramming tool, the special GM access codes, and new software code from an expert performance hacker.

DrD
Have you heard of any companies that have this ability yet?
 

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Jet Chip Performance now has a computer module for the 2008 LTZ 3.6l V-6. I have mine ordered and should be in by next week...
 

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I had my last two Silverados done. They re program the ECM (engine control computer) .They have mail order which you order and then change the computer when it arrives. It s very easy to change. If I remember its on the drivers side under the hood, towards the front and it s silver. The other method, which is better, is EFI live, which the laptop is in the car and while you drive the programmer changes the parameters of the computer. Mostly advancing the timing which requires a higher octane fuel than regular. Changes shift points and firmness.It s a remarkable improvment for the money. Runs from $100-$400 or so.
 

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I'd like to see real world tests of the performance and fuel economy changes this makes to the Malibu before deciding to buy it. I know the results for most full size GM truck owners have varied wildly for the fuel economy side of the coin, though the power numbers have been much more consistent.
 

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CuriousC - If memory serves me correctly, some of it has to do with the fact that when you make these "modifications" the wear and tear on certain parts increases thus shortening their life. "Squeezing" out more from the engine inadvertenly puts more strain on other components thus warranty coverage would increase.
 

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I don't understand why this isn't done from the factory if it provides such great results?
alot of the timing changes are not done beacuse of the added fuel requirments (higher octane). Some states have much better fuel than others and the car needs to be shipped all over the country and not have any issues. As far as additional wear, there is some depending on what changes are done.Mostly changes to the transmission. The engine is only adversly affected if the timing is advanced for more power and someone keeps putting in a low grade and octane fuel.
 

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CuriousC - If memory serves me correctly, some of it has to do with the fact that when you make these "modifications" the wear and tear on certain parts increases thus shortening their life. "Squeezing" out more from the engine inadvertenly puts more strain on other components thus warranty coverage would increase.
Oh that would suck, I wouldn't want any modifications on an engine that makes it less reliable.

alot of the timing changes are not done beacuse of the added fuel requirments (higher octane). Some states have much better fuel than others and the car needs to be shipped all over the country and not have any issues. As far as additional wear, there is some depending on what changes are done.Mostly changes to the transmission. The engine is only adversly affected if the timing is advanced for more power and someone keeps putting in a low grade and octane fuel.
I didn't think you would need to run a higher grade of fuel unless you added some form of forced induction (Super/Turbocharger) to the car. Wear would be a big thing, I guess they could put in parts that can tolerate the extra stress but at this point your speaking big bucks.
 

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No, Increased timing along would require a higher octane. Ive done this to two Silverados and I was happy with the results after much research.
 

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I believe your service department is mistaken. Yes the Malibu 3.6 has the same engine as the CTS but it is 263 HP base model. The 304 HP engine is the Direct Injection upgrade which I believe is more than programming and intake (it is a completely different engine). I have heard as well that the difference of 11 HP in the base CTS vs. Malibu is simply programming.
I was told by the dealer the 3.6 chevy engine is direct injection!
 
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