[bimmer83]

LZ4
The LZ4 3500 is an OHV engine based on the 3.9 L LZ9 V6. It was introduced for the 2006 model year in the Chevrolet Impala and Monte Carlo. It includes continuously variable cam timing (fixed overlap). It has a cast iron block and aluminum heads. Output is 211 hp (156.5 kW) at 5800 rpm and 214 ft·lbf (298 N·m) at 4000 rpm. Bore is 99 mm (3.9 in), stroke is 76 mm (3.0 in) for a displacement of 3510 cc. Horsepower rating changed for the 2007 model year to Horsepower: 224 at 5800 rpm and Torque: 220 at 4000 rpm. The Chevrolet Malibu, Pontiac G6, and Saturn Aura became equipped with this engine for 2007 (previously the Malibu and G6 had the non-VVT 201 hp (150 kW) 3.5 L LX9). In 2008 SAE ratings dropped the horsepower ratings to 219, keeping torque as is. On Pontiac G6 convertible models, horsepower was rated at 217.

Now does that mean my 07 has more HP than others and is that at the crank or @ the wheels??

 

[bimmer83]

Not necessarily. Here's the key passage in the Wikipedia article that you quoted:

"In 2008 SAE ratings dropped the horsepower ratings"

This could mean many things: There was a slight change between the 2007 and 2008 model year (not probable), SAE decided to remeasure using more refined criteria and found that the HP ratings weren't quite the same as they were before (pretty likely), there was a difference in the fuel mixture that day (could be), and so on...

Thinking your vehicle is superior because you might or might not have 5 extra horsepower is like thinking you have a superior, um, thingy because it is a quarter of a millimeter longer than someone else's - especially if your ruler is artificially shorter (therefore giving longer readings) than everyone else's.

Really, it's not about how much horsepower you have but whether or not you know how to use it correctly. The more critical component for getting you off the line and up to speed quickly, torque, is identical between the model years.

~ MattInSoCal

LOL, Thanks for the 3 page reply but really all I was looking for was how to tell if I have the LZ4 engine... And I do feel superior to previous year G6's with the 3.5 since I have 24 more HP than prior year G6's unless I don't have the LZ4... since the car is a 2007 it still was manufactured in 2006 catch my drift???

 

[bimmer83]

pop ur hood and snap a picture, post it up here and I can tell you what it is.

I gotta get one but is there any tell tale signs on the engine that would stand out to show if it is the LZ4?? because the car is a 2007 but it was manufactured in 2006 so i'm not sure if it has the LZ4

 

[bimmer83]

Thanks everyone for info =) I checked the VIN and I do have the LZ4 thanks alot Lampoon & MattInSoCal

 

[bimmer83]

Hey everyone, I'm back again and about to tear down my whole LZ4 and stroke it to a 3.9 and change my AT transmission to the 6 speed Manual. Found the trans on EBAY for 525 NEW and all the linkage,shifter,Flexplate,Pressure plate,Clutch,clutch lines clutch pedal everything it needs straight from the dealer minus my shop discount componets will set me back an extra 1200 to 1500 I am sending my heads in for port polishing and 3 angle valve grind.. I was thinking I could put LS6 or LS7 valve springs in there while everything is being done. Has anyone heard of this being any better than stock or incresing RPM which of course increases HP??? I was thinking about keeping the 3.5 intake on I read somewhere else a GM engineer said the 3.5 intake flows better than the 3.9 with the controlled vanes inside. anyone know about this?? I really wanted to install a super charger but I have not seen anything or any Engine modifications for this engine is it just me or is no one interested in making the G6 go faster???

 

[bimmer83]

Also does anyone know if the harness for the automatic trans is different from the manual trans I would asume so but not sure I would think all the speed sensors would be the same which is all i'm looking for I don't need a clutch switch for staring since I'm not like all those dumb asses in america they made it a law for a clutch release switch to even start the car? Also I know I need to change the ECM when changing the trans out so I was looking for a used engine wiring harness and ECM for Manual trans and that I can send out for a tuning flash.

 

[bimmer83]

Honestly Yeah I was looking at the older Pontiac GTP engines and it looks like the upper intake would work but would need to fabricate some intake spacers so it would bolt up properly

 

[bimmer83]

LOL Lampoon I'm a Mechanic so it won't cost me much since I do all the work and the shop I work for has 7 dealers so I wouldn't even need my car while its all being done I could just use dealer cars to go home with