Psi?

[-cj-]

Hey guys,

Just collecting some data. Has anyone's boost targets changed in the last 2 weeks? Are you guys still hitting the same peak / average PSI under WOT as you were in the warmer weather? When I bought the car last year, I bought it in December and it was already cold out. By the time I got a boost gauge, it was already warming up... So I've never done the warm weather -> cold weather transition in this car before.

Yesterday I was having trouble holding 12-13psi at WOT in 3rd, 4th or 5th. My peak was 15.X PSI. Today I hit 16.8 psi and was holding at 13-15ish. In the past I used to hold at 18 psi all day long.

Just looking to see how you guys are fairing before I post any logs, etc. The car is running fine though.. No more hesitation or anything. I did a few pulls and it still goes like a bat outta hell...

[Zoom Zoom Boy]

I haven't noticed any changes, other than the change with adding the COBB SF Intake.

[Fobio]

prior to your install, did you chk to see if the FMIC and its piping is air-tight?

nothing wrong with my cold-weather boosting...I'm hitting all targets and expected spikes, and spinning 3rd gear sometimes.

[-cj-]

Going to have to double check, but everything seemed fine. Although I'm getting horrible gas mileage, but what else is new ;) My LTFT is a little high, 4. Going to dig through MSF and see if they have any good boost leak tests.

Wouldn't a boost leak show up on my gauge? Or some other way?

[Fobio]

Wouldn't a boost leak show up on my gauge? Or some other way?

chk AFR and MAF values.

[alhope34]

When I had the AP I would spike much higher in cold weather. All winter long I was spiking 22.5-22.9psi with stage 2+SF v1.03 93 octane with sunoco 94 gas. Would hold 19.5-20 psi till 6500 rpm. In the spring when it started to warm up it would spike around 20-20.5psi and hold 19-19.5 till 6500 rpm. I used the same map all the time I owned the AP.

[-cj-]

Figured it out! Loose clamp caused one of the silicone couplers to leak... Boost levels are starting to look normal again. ;) *phew*

[Fobio]

3:30 am eh...lol...nice!...late fri night tuning FTW!

call me when you see this...I got something lined up and ready to hook up later =)

[spd frk]

That is weird I seem to get the opposite results of everyone.

I am back to stock, so I get spikes now to about 16psi but it holds only 12psi to 5500rpm. This in in 0 degree weather.

Last year when it was -25 outside I could only spike to about 12psi and hold maybe 9psi.

With the AP it was better at holding boost targets. I have checked for leaks everywhere and am pretty sure everything is tight. I assumed the wastegate control solenoid is not active and has basically one setting to maintain 15.6psi at a standard temperature and pressure, but our winter temps were so different it couldn't make proper boost.

i.e. it opens the wastegate too much in the cold weather to see proper boost.

[Fobio]

I can say now that in 2 celsius weather @ WOT, I'm down about 10% boost now or ~2psi...still spikes 19 tho...

[-cj-]

I'm holding at about mid 15psi, spiking at 19. Someone told me it's most likely a load issue and I should tweak the map. I used to hold 18-19psi all day long with my old TMIC :)

[Fobio]

those MSF guys are looking into more tweaks with ATR...but personally, ATR as it is right now is not the answer...we need a little mopre control than the tables already available...

that or an etune will be sufficient for now...but this cold weather boosting limited by calculated load is tricky...