I was driving around today and noticed that I could only get about 12 to 13 PSI of boost. Is this normal when it's cold out (37 deg.) I seem to remember getting more like 15 or 16 when it was warm out.

 

yup that's normal dood, GM made this car smart so it always makes 260/260 no matter wat the weather conditions or altitude ect ect.

 

thats both good, 'cus theres no way to exceed limitations of the hardware, and sucky, for obvious reasons.
learned something new.

 

Thanks. That would make sense, and I have to say that the power feels normal.

Can anyone confirm that they also only get 12-13 PSI when it's that cold out?

 

I'll jump on mine on the way to work tomorrow and let ya know.

08 SS T/C, Victory Red, LSD, High wing spoiler, sunroof.

 

I make about 14.5PSI right now with the temperature just above freezing, the altitude here is also about 5000FT. Also the max I've seen is about 18PSI

 

I'm just above sea level, which probably means that I don't need as much boost to make 260/260.

 

correct

 

my ss/sc is quicker in the cold ha ha...lol

 

but slower in the heat who's faster? the guy driving in snow or the guy goin down the 1/4 mile on a hot sunny summer day?

 

true...my 1/4mile time can beat up your 1/4 mile time

 

Correct I'm originally from michigan before I was tuned drove back and only ran about 15 psi in michigan ran 18-20 here in 5,000 ft elevation. Since hahn tune it's 25 psi no matter if it's 20 degrees or 100. ran tune since August.

 

probably not, because most people will be making different boost levels.

but it makes sense to boost less in the cold and make the same power.

 

Should cold weather affect gas mileage?? I know it will run leaner until the engine is up to tempature.

I am not sure if the winter blend gasolines have come out yet or not but I was expecting to easily get 30-32 mpg on the hwy(espcialy since the EPA made the rules stricter). Most of the time I will set the cruise at 70 and it will usally average 28. However if I follow someone i jumps to the low-mid 30s.

Just wondering if all TC were similar to this.

 

Yeah.. lol so is mine...

Kinda weird but shouldn't the SS/TC be making more boost during colder weather? I thought colder air was more beneficial to turbocharged engines?

 

our turbo balts are NOT affected by altittude what so ever the car adjusts accordingly... As for boost i was getting 15.5psi and its -2 degrees celcius here

 

Confirmed.

 

Brrr f'in brrr and my feet are cold at 29f

 

~3,400 feet

 

Thanks.

 

On a 90 degree day mine saw 19psi...now that some mornings are in the low 40s its seen as low as 13psi.

Still enough to outrun a bolt-on 98gt by car lengths

 

how do you figure?? Every engine loses HP as altitude increases.

How does the computer make up for a lack in 02??

They have altitude correction tables for forced induction cars because they too---suffer--and you can correct to sea-level.

 

Though poorly worded, I think he simply means that in the case of the TC the engine is "effectively" unaffected because 260/260 will be maintained regardless of said altitude.

 

i was boosting only 12psi today too and it was 32deg

 

1WhiteSSTC sent me this article which explains it best

http://editorial.autos.msn.com/artic...umentid=473407

to paraphrase:

GMPD took an innovative approach to the gutsy four-cylinder. Instead of tuning to a prescribed boost level, the ECU targets a constant torque number using a variable boost strategy.

Ambient air temperature and absolute air pressure are two of the main tuning parameters. So on a cool night with dense air the turbo may only need to produce 13 psi to hit the mark. But on a hot summer day it will unleash up to 21 psi in its efforts to deliver the goods



ok I am sold--if GM designed it to maintain HP in high elevations by varying boost levels--good enough for me I just need some explanation. I don't beleive every forced induction engine does the same thing though.

bet he was talking about density altitude.