Brandtaaron

I have a few questions about supercharging a N/A 2.4 SS. To anyone that has done it, is it worth it? Will I have engine problems? My SS has 145k miles on it so I know I risk blowing the engine, but obviously don't want that to happen. How much am I going to end up spending? Thanks in advance.

Slowbalt2000

iTrader: (1)

If you read the threads in the forum you posted in you will find all of your answers.

https://www.cobaltss.net/forums/how-...through-80620/

chevygirl2006

Ya it's worth it

steelmesh

I think boost on any engine is worth it, if you value acceleration g-forces that is

Cobalt_noob

hey steelmesh, did you have to drop the compression ratio on your LE5?

AHelm3

iTrader: (7)

I say go for it! It's a simple and straight forward swap. And affordable, low mileage LE5s are allover the place.

The parts are cheap, readily available, and if your motor does pop, you have the advantage of getting a new one very cheap.

07blackg5

iTrader: (8)

no

Slowbalt2000

iTrader: (1)

Stock is fine

Cobalt_noob

Even at 16.5 lbs of boost???

Granted being the 06-07 LE5's with forged internals.... but that just seems cray cray.

Cobalt_noob

AHelm3, you still got a 'balt and whereabouts in the Pitt area?!

07blackg5

iTrader: (8)

Long story short, yes.

Cobalt_noob

lol, cool story bro.

Better yet, at what point of boost would you have to drop compression ratio?

07blackg5

iTrader: (8)

for all realistic intents and purposes, never

AHelm3

iTrader: (7)

I sold mine about a year and a half ago. But I'm currently working on an Ecotec swap so I still hang around.

I'm in the Carnegie/Mt.Lebanon area.

Cobalt_noob

Man, im prodding at this one.. there has to be a point to when you would drop. i mean, at what point do you have too much air and fuel in a small compressed state. Unless youre implying that it would be unrealistic to go over a certain point of boost on these cars??

If you can explain in the least amount of words, that would be a challenge because im sure it has a long winded explanation...

Cobalt_noob

Nice man! I work right at the airport and live just past Elizabeth.

If ever in a pickle, do you know how to tune at all? Ive got the general concept down. Just never could find anyone in the area...

AHelm3

iTrader: (7)

I personally don't, but I can give you some local leads.

That sounds like a pretty shitty commute you have there lol.

Cobalt_noob

lol it is in every sense of the word shitty.

But yeah man, thatd be cool.

So are you doin a personal ECOtec swap or for someone???

Slowbalt2000

iTrader: (1)

Boost pressure does not determine horsepower, airflow, or what compression ratio you should run.

Cobalt_noob

Well, i figured as much for HP and Airflow, what i cant figure out is what affects compression ratio???

So, at what point can there be too much air for a cylinder to hold before it is no longer efficient??? Or am i way off track in my questioning?

Slowbalt2000

iTrader: (1)

Higher compression ratios are more efficient by the laws of thermodynamics. Lowering the compression ratio is just going to net you less power. Unless youre going for 700+hp, dont even worry about it.

jdbaugh1

iTrader: (1)

The general issue is higher compression leads to higher cylinder pressures and more heat which requires extra cooling and higher octane to prevent detonation or per-igntition. So the compression ratio you want to run really depends on what cooling mods, fuel, and how close to the edge you want to run it.

Slowbalt2000

iTrader: (1)

^^exactly. Basically if you have good e85 you can run pretty high CR and be fine, but if youre limited to pump 93, 10:1 or lower is probably best.

Cobalt_noob

Good explanation!

There has to be posts out there, but for just a quick reference... how much boost is permissible on 93, for an LE5 before detonation or pre-ignition occurs?

Would a dual-pass help with combating this???

Good reference to come back to ill say

chevygirl2006

That's not how it works. It's not about boost. It's the timing. Higher compression tends to knock on lower octane gas with little timing. When I was on 93 we could only run 10 degrees of timingbefore it would knock. Now on e85 I'm at 23 degrees.