the owner of one of the red ones claiming the most HP works at town fair tire in southington. i talked to him one day when i went for an alignment and he was telling me how it was his toy and he had a 700HP cobra at home. other than his bullshitting he seems like an ok person.

where abouts in bristol? ive never seen you around.

 

You've never seen the orange one around? I think we see that thing at least once a week. It's the only orange one I've ever seen.

 

I stand corrected. Either the GTO drivers in the other stories were horible or some of the other Cobalt drivers are full of $#!%.

I didn't mean for this to turn into a war, I was just stating what I had read a while back.

 

Not trying to start a fight, we have done more then enough of that over the last couple of days.

By using more aggressive cams that move the curve up ~1k rpm, with the redline set at 8k, there are several people on this board who would be making over 300whp.

The smaller pulley will also give a much longer flatter torque curve then what you see out of the 2.5", which tend to hit peak torque lower then stock/stage 2/stage 3 cobalts and then see a steady drop as their heat levels shoot up.

The lower manifold pressure will generate less heat and keep the blower out of the zone where it is inefficient (and if your lucky enough, get it to near its peak range). This lowering of heat and pressure will allow you to run more aggressive engine timing and make you less likely to knock. Since the LSJ is a knock limited engine at WOT, this is a very good thing and can net significant power gains. Again, this is where the crazy tuning comes in.

Also, the SC will be moving more air if the manifold pressure is lowered, since this will allow it to operate at a higher thermal efficiency.

Now that I'm on the subject, I would like to point out that even the stock LSJ will see performance benefits from improving its breathing ability since in stock trim it is operating above the M-62's peak range (8~10psi if I remember correctly, been a while since I looked at the graph). If you can get your manifold pressure down to 8psi through most of the range, with a peak of about 10psi, your torque curve will flatten more, with higher torque (and thous horse power) at higher rpm.

Tuning would still be very important since your timing would have to be tweaked.

Finally, I don't see it being possible to make over 300whp safely with stock internals. Not saying it can't be done, but as evidenced by all the blown motors on this site, it can not be done safely.

 

Not safely with the M62...With a more efficient supercharger or turbo a safe tune, and proper cooling mods, I don't see why we couldn't push a bit over 300hp safely. The guys that have blown their motors on here, were still using the M62, and were definitely pushing the limits with tunes...

 

Thanks, I meant to say "can not produce over 300whp safely with stock internals and the M-62". Changing out the compressor to a more efficient one will allow safely making over 300whp on stock internals. How much more, I can't say until we have enough cars running around with a turbo/twinscrew swap and stock internals making over 300whp to see when they start blowing up.

 

Anytime. Yeah, I was hoping to try pushing those limits a little with a swap of my own this winter, but with some BS family drama that has come up, I may have to put it off a little. Grrrr

 

Sorry, you lost me there. I didn't even read the rest of your post.

Never ASSume anything. Keep that saying in mind, to assume makes and ass out of you and (in this case) whoever you're assuming for. Until it's done, it isn't possible.

The blower is not capable of flowing 300+hp worth of air. It doesn't matter where you move the torque curve, how much you improve engine breathing, etc. It still needs to flow the air required to produce 300+hp and it simply can't.

 

There you go assuming yourself. There was a discussion a while back and actually it does flow enough air to support 400 crank hp. As a matter of fact there are several people on this board making over 300 crank hp right now.

Since you know a great deal about boosted engines, can you tell me what happens when you make changes in a knock limited engine that makes it more resistant to knock and tune accordingly?

 

Based on that I don't really see it supporting anywhere near 400bhp. I guess I could see it cracking 300whp if you did all the work you were talking about and were able to flow retarded amounts of air at low boost. It'd be a stretch, but I'll give you the benefit of a doubt that it will at least work in theory. As I've said in other threads though, CFM is a worthless figure so it's hard to say for certain without a lot of math that I don't feel like doing.

But obviously you can't go by flow alone, because that's only one part of it. And this why it would REALLY be a stretch to make that much power.



It pretty much speaks for itself. At the speed you would need to turn the blower to flow that much air, even at lower boost (say like 15-17psi) it would be BAKING that air out.

 

someone already made 425whp on the stock blower with 10.5:1 pistons, ported head, cams and race gas..... riceeater from the rl forums

 

Plus your looking at the wrong generation of M62 with those charts.

 

sure less knock equals more timing, noone is arguing that. but if you have something that can only flow 20lbs/min worth of air into an engine, no amount of timing is going to make up for that 10lbs/min extra you need to produce 300HP. thats what hes getting at.


fixed it for you

 

If you don't have a cobalt or not interesting in getting one leave thew forum. I'm tired of people comming on here, if your so worried about it find out yourself. BTW, its not that hard to get 300 wph in a cobalt anyways.

 

Thats the thing, you don't need to flow more air. The LSJ is severally knock limited. Lowering the manifold pressure, even though your not flowing more air (and you would be due to the increase in thermal efficiency, but lets not go there), will allow a large increase in engine timing. The people right now running in the high 200 whp range, if they performed extensive head, valve, and exhaust work to make the engine breath better, could lower their manifold pressure enough to break 300whp.

In fact, people have done it already. Mostly though they force it with dangerous tunes while not doing things to make their engine more resistant to knock and blow something.

I'm not saying it is cheap, just that it can be done.

 

No one has to leave, this is a public forum. Also, it IS hard to get 300whp in a Cobalt. Anyone who thinks its "easy" is living in the same fantasy world where stage 2 cobalts smoke LS1 Camaros and LS2 GTO's. See comment below...

I'm sure with some really good setup with alot of research and knowhow you could crack 300whp with the stock blower, that wasn't the point of the thread. There's a couple of Joe Shmo's running around claiming 300+whp and oh how easy it is.

 

The blower flows enough air to make 300 whp, but the key is in limiting how hard the blower has to work for it. The better you can flow that air through the engine, the lower the boost will be. Lower boost = less work being done by the blower to move the same amount of air = cooler IAT and more hp being directed to the wheels instead of being spent to spin the blower.

Damn, that turbo swap is looking better and better by the day...

 

which is exactly why every is doing it right?

 

Oh my god, I'm actually agreeing with CRX on this one. AWDstylez and me are still cracking at each other though so I guess I didn't fall into the twilight zone.

 

ARG, another new member being a smart ass.



Ignore me man, I'm in Iraq and get really grumpy at times. Fight/arguing is very good stress relieve until I get to go blow **** up, which doesn't happen often enough for my sanity.

 

I have an idea. Suck.... my.... dick....

If it's not so hard, why don't you have one? Enough of the import/faster car envy. Grow up.

 

the time in my sig is a good example of what the gto can do in the hands of a good driver stock

 

At least someone is on the right track.

Wow, so many GTO owners on here. Awsome time you ran on that thing!

 

Damn PhantomGoat06. a 1.89 60' is nasty.

We won't see that in a Cobalt. AWD, you comming tonight? McD's

 

Planning on it, temperature drop dependant. Trying to get some other people to go too, I don't feel like driving up alone.