Eaton and Efficient should not be used in the same sentence. If a M90 was swapped into the 62's place.. You could make more power with Less Pounds of Boost.

 

true, but i'll take a Gen V m62 over an earlier generation m90, but give me a Gen V m90 and i'll call it a day (the 5th gen m90 is more efficient than a P&P 4th), not to mention their new front inlet design that hasn't even been used in any application yet


scratch that, just give me a 2300ax and i'll be happy with that... it's kind of pointless to swap out to a used m90 anyways

 

I like the interior of the cobalt, some say it's too european. just like alot of the Camaro/trans am guys don't like the foreign interior design of the GTO.

 

thats recockulous! so american cars are starting to get nicer and people complain! the GTO has a real nice interior, and the cobalt seems to be the same, hopefully GM will stick with it and upgrade the whole lineup, it would definitely bring sales back from the imports

 

Part of the appeal, to me at least, of the Cobalt is the more European style interior. My friend has a 2001 Audi 1.8t Quattro..and comparing his interior, with the pictures of the Cobalt...even he admits the Cobalt's interior looks amazing (for an American car). Add the Ecotec on top of that, and I'm sold. There's no real sense in trying to debat what the SS can and can't do. Fact is, the car ain't out yet. We have projections (based off the RL)..but, no one will know for sure until the day someone starts tuning. Until then, we can keep fantasizing and drooling.

 

and just wait till people start playing with the cams......

 

and twin screw blowers...

 

And wings!

 

The biggest Limiting Factor now is the ECU limiting boost. Crack the ECU and the door is open for smaller pulley's and such.

 

ahhh, so i'd like to say something on that. right now i'm not sure, BUT when the headers were developed for the RL, they noticed that the boost levels stayed the same, but gained an unexpected amount of power. i have a theory on this, and i made a lengthly post on redlineforums, but my theory is that since/if the computer limits boost, opening up the exhaust will drop the boost down, but since the computer wants to limit it to the 12.5 or so PSI, when you open the exhaust, lowering boost, the computer doesn't limit it until it gets back up there. i don't think messing with the computer needs to be done until intake/exhaust are both opened up FULLY. then cooling issues should be addressed, as i believe you have stated previously on these forums, then a pulley swap and PCM re-tune, or just re-tune, and we should be where the 270hp cobalt was at (and they didn't change the headers) possibly with only the use of an SAFC

 

Exactly. You will actually decrease the amount of boost pressure when you open up the exhaust. What i'm saying is that the ECU needs to be hacked to increase boost Past 12.5 Psi. As we all know.. The M62 is Maxed as it is from the factory. Adding a smaller pulley is only going to add more low end torque and not add much top end horsepower.

Also.. What does the Redline guy's A/F look like? Is it VERY rich? Can gain some power leaning it out.

 

not sure on the A/F, but i know the blower is spinning at close to it's max rpms

i don't even think we'll have to switch pulleys, maybe just up the boost limit and open things up! i'm loving this car more and more by the minute

 

Maxed from factory? If it were an m45, I'd agree..but an m62 should be able to handle up to 20psi just fine. That's been my understanding and experience, as far as what I've seen and read. Any reason for feeling 12.5psi is max on the m62?

 

the problem isn't max boost, it's max RPM

if you have an extremely restrictive engine, i'm sure the m62 can push 20 psi, it's just the engine handling it. you can check out eatons website for the graphs on it, but with a pulley ration of 1.85:1, it's spinning at ~12000 rpms, the charts stop at ~14000

as stated before, opening up exhaust reduces boost, but when a set of headers were test fit and dyno'd on the Redline, boost levels remained the same confirming (hopefully) that boost is limited to an extent. theoretically boost should drop with a set of headers that net ~25-30hp to the wheels, but it didn't. that means the more we can open up the engine, the more the computer will let in!

i'm sure the pulley on the redline/cobalt is good for more than 12.5psi, it's just that the computer won't let it, so that's all you see, but by opeing up more of the system, you unleash the potential of those limits. if we could get the computer to stop limiting the boost, i'm sure we'd see more than 12psi STOCK

i'm actually interested in what RPM we start to see that same 12psi, and if it comes on early in the RPM, it seems to me like we get full boost by 4kRPMs

 

thats what im wondering...when that 12pis starts becoming constant because of the computer...man i cant wait to see the mods possible for this thing...this is gonna be interesting...

 

Which leads into another series of questions. The first of which would be: What's the stock valvetrain like? If we're talking cracking the ECU here, why not crack it to raise the redline? I'd be curious to know what it could handle..and if it needs a bit of reinforcing, what could be done about that (GM performance VT kits, or aftermarket, etc.) In theory, with all that you're saying and we've seen/know...opening up the engine (I/H/E), then cracking the ECU to raise boost and redline, perhaps...man. That'd be pretty damn nice.

 

I don't know how high the stock valvetrain would handle 7000+ rpm but you also have to worry about the stock Connecting Rods and such.

If you crack the ECU and allow the engine to rev to 7500... You will increase boost pressure on the top end.

 

you guys need to read the motortrend review about the SS very good review and has the 1/4 time and 0-60

https://www.cobaltss.net/forums/general-cobalt-68/motortrend-ss-article-827/

 

I belive the connecting rods on the LSJ are forged , combined with the short stroke of the 2.0L the rods will be fine, you will be able to hit 8000 RPM.

If anyone wants to do some searching to find the max tensile load, and max compressive load of the con rods i could calcualte the max hypothetical RPM before the rods snap.

Just a question but why it this discussion under the post title of LSD.

 

to reply to the m62 power limit think about this.
1994 pontiac bonneville ssei has a 3.8L with the m62 and it produces 225hp it revs to 5.5-6k
they add pulleys to them to make around 11psi with no intercooler. now 11psi on a 3.8L engine and the cobalt is only 2.0L is has the possibility to make alot more power.
also note that thats a 1994 model m62 they may have made it more efficient since then.





Nicolas

 

The Cobalt SS 272 at SEMA apparently made peak hp at 7000RPMs. That was with stock internals and valvetrain.

 

According to GM the ecotec's connecting rods broke at 285hp @ 4400rpm on the dyno.

 

Don't know if this was said yet.

But I went to buy a Redline today (didn't...glad too) and I was talking to the managers and stuff at the dealership. I asked about this elusive performance package.

He said "YES, Its called the Competition package, it will come with a boost gause, tach, LSD, and colored wheels" I asked how much "about 1450" he replied. When, I asked " we will be able to order them mid February"

The LSD is not an illusion it will be here in a month. I also asked, this is NOT going to be a dealer installed option, it is a factory option. Sorry anyone who bought one and wants one

BUT you can get them from Quaef (sp?) that bolts in.

 

im pretty sure that was the connecting rods from the 2.2L.

 

it was, we have ugraded rods in the 2.0, among other things