I mean we all see how terrible a 2.4 with boost really is. I mean look at the SRT-4's and the old SVT Mustangs that ran boosted 2.4's in them. I mean sure they coule walk a 5.0 EASY and weighed less and got better gas mileage......wait.....um.....

A boosted 2.4 IF Gm had decided to do it would have been a killer for sure! But the fact is GM wasn't ready with it due to the VVT (at least thats what I understand) Plus you have to figure CARB standards and EPA compliance. I KNOW the 2.0 had problems so the 2.4 probly just spewed too much nasty stuff from the tail pipe to be able to be made.

 

When making any car or engine, they don't think about it for a day and say "ok lets do it". They were using a 2.0 engine before it was dubbed the LSJ in their race engines (I believe as far back as 2003...maybe sooner). This leads me to believe this was planned far ahead that they wanted to utilize a 2.0 motor...which is why all the forced inducted ECOTECs are ALL 2.0L Engines from factory (LSJ, LNF, LK9)

 

Yeah; also, from talking to people who have toured some of the plants in Detroit etc., as well as other foreign manufacturer plants, I have learned that most manufacturers actually have a prototype of any possible engine choices they may use. For instance, Mercedes actually supercharges and turbocharges most of their naturally aspirated engines to have it on hand. If they need to use it, or can use it and still meet emissions they will.

In other words, the manufacturers know what they are doing and have back up plans at all times. This is how they are able to survive and continue the "I have something better than you battle" effectively.

 

Exactly. These are billion dollar corporations...they aren't going to under think anything or do things on "whim".

 

ok here's an idea that i ahve been thinking about since this thread started, why not instead of just lengthening the stroke also bore the sleeves out to the point that the bore and stroke are back to square, that would probably make the kind of power your looking for. i haven't done the math but i imagine that would put you around 2.6-2.8 liters. boosted it would probably make very good power, but and there's always a but you would have to have the heads machined to match the bore diameter and to make any real power have the heads ported. another problem is the integrity of the sleeves at this point.
but if you could work through all of this you'd have one hell of a 4 cylinder engine.

 

Boosting a big displacement engine will always have its adv. and benefits over boosting one with smaller displacement. Going back to the good ol saying "there is no replacement for displacement"

you start big, you will end with better number than someone with a smaller displacement engine

 

You would have very thin cylinder walls.

You would have to make a very large bore change in order to see any significant displacement changes. Seriously would have to be a significant overbore (like .060). With forced induction, it's best have stronger cylinder walls especially with increased cylinder pressures.

 

oh i'm fully aware of all that, i was just throwing it out there, kinda like food for thought.

 

Gotcha.

 

It's pretty apparent that most people are simply missing the fact that the LE5 was not a production engine at the time the SS/SC was in R&D....

The LSJ had been used in the Ion Redline since 2004 model year, so production since mid-late 2003. I do beleive the engine was made for the Cobalt SS, however the Ion was ready a year earlier (possibly the cobalt was having other production research done still?)

In any case... the LSJ was readily available and in production when the SS/SC hit the streets for the 2005 model year (mid-late 2004). The LE5 did not see market usage until it was used in 2006 in the Cobalt SS/NA, Ion, Solstice/Sky.

Simply put, they designed the LSJ around FI and had no reason to build a bigger displacement engine. I'm sure if the 2.4 was in production at the time they would have concidered it as well.

 

Exactly. That's basically what I said as well.

 

Not to mention FUEL ECONOMY...

 

under a warranty/liability stand point a 2.4 forced induction would not make sense. Even if they released it at 260 to 280 whp, It would be so easy to mod to get 350 to 400 whp and you would have to redo the trany, driveshafts, suspension, stop the wheel hop....just to be able to warranty it for 5/100 and could you see a 16 or 17 year old kid driving this with little or no experiance even in a stock form? And fuel economy would probly be good ... Hahn has said they get better fuel milage TC"ed i believe.

 

Our fuel economy would be 10% better if gm actually took some time to design decent ratio's for us. They're too damn short. Our current gearset might have been good for a 3.55 final drive or a 3.27. Not a 4.05

As for the LSJ being 2.4L's. Would have EASILY put down 250whp and 230wtq on stock boost.

 

....and it would have been pig rich.

 

True.

Gm would have been badass if they used a 2.4L LSJ with 42lb injectors and a stock boost of 6-8Psi.

 

Why? Making gobs more hp doesn't mean your gonna be running "pig rich"

 

Preventing detonation with a richer a/f mixture.

And this is also depending on how aggressive the ignition timing maps would have been.

High Static Compression + Less Efficent Compressor

Even with the 9.5:1 Compression the LSJs have, GM kept them at a pretty rich command a/f ratio. It would be worse with higher compression fighting combustion chamber temperatures.

 

Sooooooo lower the comp ratio and TA DA! Problem solved!

 

I'm still trying to understand why gm went with 9.5:1. Why not 9:1 or 8.5:1 to be safe?

 

I amazed this thread is still civil.

Obviously though, GM sees potential in the 2.4l VVT, because they are hanging with it and the 2.2l for the 08+ Cobalts. The LSJ is out because of California , but GM really doesn't need to give a choice of engines in the Cobalt.

 

So true. They could simply just ditch the performance market all together, but they don't want to. At this point, they have already said they want to bring out another performance engine, and they have also said that they have a large interest in keeping it forced induction. So, we'll see what happens next year.

 

I was stating as the motor is in it's current state

 

I know you were Adam but seriously man don't you think that had GM boosted the 2.4 they would have dropped the CR? I mean its GM not some backyard hack!

 

I know they would and I even said that they would in a previous post

But if someone says "the 2.4 motor" I'm going to talk about it in it's current state which alot of people were even talking about it in it's current state.