Ok. first im sure there is already a thread for this. However there is too many pages to go through, and I have used search. I dont know maybe it is just me, but I just bought a 2006 cobalt ss(used) and all i want to know is how much the engines are built for? What is the limit the internals will take? Thanks for any help.

 

anywhere from 330 whp to 350 whp at extremes... the clutch or other stuff might fail prior.

 

you wont make it past 300whp before losing cylinder #4. I would say 260whp is about the limit after that it is hit and miss. The Tune is a major key factor too

 

Most agree that as you approach 300 crank hp, reliability takes a severe hit. It does all depend though how you get there, whether its running the stock blower far outside its efficiency range or converting to an entirely different style compressor (turbo/TVS/twinscrew).

 

Okay, this is a subject of hot debate on this forum, and in reality there have been quite a few blown motors as of late. So i'm going to give you a purely opinion based assessment of what this motors limits are.

First off, most of the blown motors are due to A) bad/out of season tune B) pulleys that are a little to small C) lack of cooling/supporting mods. This is not the case for everyone, but you will find that very few 2.0's have been blown with just stage 2 (3" pulley and rich tune).

I personally don't know of any 2.0 that has had internal failure while just using GM performance parts.

Due to the overwhelmingly bad feedback that i (again just my opinion) have heard about aftermarket "canned" tunes, and pulleys smaller that 2.85, I would steer clear of these. Unless you plan on doing some severe cooling, porting, and PROFESSIONAL tuning mods.

The above poster was right in that many people blow there motor around 270-290 whp. I personally think this is because many people keep pushing the limits of the blower with smaller pulleys.

So to answer your question, i think the stock internals are capable of 300whp with the following setup, excluding traction and suspension mods.

1) GM stage 3 (stage 2 required)
this will include: 2.99" pulley, stage 2 belt, 42.5lb injectors, dual pass intercooler plate, stage 3 pcm
2) header (gm, CA, etc)
3) catback exhaust (gm, corsa, etc)
4) downpipe
5) hi flow filter (or CAI if you have an extra 200 bucks burning a hole in your pocket)
6) 50'ish shot of nitrous (stage 3 pcm will accomodate this as safely as possible)
7) tank full of 100 octane

This is basically what GM ran in the time attack cobalt, which still runs fine to this day. Of course it had an upgraded master cylinder (or was is slave?) but you should be able to get buy without that.

There is a dyno sheet posted of a roughly stage 3 cobalt minus exhaust, 100 octane, and no adjustment for the nitrous hitting in the 290's.

 

is it a Cobalt SS Supercharged, or Cobalt SS?

He really didn't specify, so i think its an N/A SS... therefore your answers are all wrong..

 

^^But he did post in the 2.0 section...

 

1) posted in the 2.0 section. He had to physically choose "2.0 performance" before typing his question. I hope to all that is holy that he was talking about a 2.0.

2) opinions cant be wrong!!!

 

You limit of SAFE power is gonna be around 265-270 whp. Anything over that, and its only a matter of time. Tune has a lot to do with it, but a really good tune will only postpone the inevitable #4 piston ring land from blowing. My car was right at, or over 300 whp for several months, then out of no where boom, #4 ring land go bye bye

 

Yeah watch out for "OL#4" It a design flaw in the fuel rail.
But heres the limit on the internals.
There is also a problem with head bolts should be replaced with studs afte 300BHP
Pistons 300BHP
Rods 450BHP with A1 rod bolts
Crank 750BHP no problem
Block reliably 500BHP (700-750 the liners crack)BHP
Oil pump should be rplaced if you plan on spending time @ high RPM
Balance Shafts 7500RPM MAX!!
Valve springs/retainers 7250rpm MAX
Stock Valves are good to 600BHP depends on many factors thoe.

 

i know this is the 2.0 thread but where can i find ^^^^ information about the ss 2.4 ?? I know they share many of the same internals but not all

where can i find^^^^ information for the 2.4 ?? i know it's the 2.0 section however I can't find anywhere that talks about these factors for the 2.4.

from what I understand many of the internals of the 2.4 are also forged like the 2.0 but I don't want to assume something then all the sudden BOOM

 

the 2.4's arent forged.

 

yea i thought they were forged too butg soon found out that they are not like the LSJ and will not handle the power like the LSJ also tyhe bottom end holds 600bhp safely definitially pistons past 300 though i plan on spray after my tune so i'll definitially need some pistons studs and cams

 

Stay under 300/