New Members Check In!! If you're new to CobaltSS, please take a moment to sign-in, introduce yourself and show us your Cobalt!!

06 S2 Supercharged lsj/ lost boost pressure

Thread Tools
 
Search this Thread
 
Old Oct 6, 2018 | 07:31 AM
  #1  
Jeremy Gardner's Avatar
Thread Starter
New Member
 
Joined: 12-22-17
Posts: 10
Likes: 0
From: Pennsylvania
06 S2 Supercharged lsj/ lost boost pressure

I bought my 06 ss this time last year, the car seemed to have something modded although the dude told me it was bone stock from what he knew of. I was building 16psi @wot an it was to quick for stock in my opinion. Besides that, I had it sit over the winter (outside) for 3 months. Battery died an wasn’t charged till spring, fired right up but threw a code for tps correlation. Put the new tb in (off a v8 vortec) 76mm I believe, with new plugs cai an a morgan catless exhaust. Bpv is a little stiff but still functional. No belt slip. Inter cooler pump functions properly Pressure tested an no leaks. No cel. The car will not build my original 16psi on stock tb an intake let alone my oversized tb an cai? Now 3500rpm is about 6-7 an wot is 10-11? I feel like It didn’t hit as hard before the mods, now it pulls about the same as before, just wanna know where my 5lbs of boost went lol clutch has a little give could that effect boost pressure? I’ve been stumped for damn near a year! My last thought is the first owner had a program on the ecu an it flashed all memory off the computer when the battery died. (Battery was dead for about a month) I’ve spent so much time on forums an nothing quite related to this matter. What do you guys think?
Reply
Old Oct 6, 2018 | 09:06 AM
  #2  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
Tunes don’t disappear when the battery dies
Reply
Old Oct 6, 2018 | 10:09 AM
  #3  
ECaulk's Avatar
Senior Member
iTrader: (6)
 
Joined: 07-19-10
Posts: 26,529
Likes: 841
From: Houston, Texas
There is a potential your old cat was going bad causing higher boost.
Reply
Old Oct 6, 2018 | 11:11 AM
  #4  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
Check and see what pulley is on it.
Reply
Old Oct 6, 2018 | 03:46 PM
  #5  
Jeremy Gardner's Avatar
Thread Starter
New Member
 
Joined: 12-22-17
Posts: 10
Likes: 0
From: Pennsylvania
Stock pulley
Reply
Old Oct 6, 2018 | 03:47 PM
  #6  
Jeremy Gardner's Avatar
Thread Starter
New Member
 
Joined: 12-22-17
Posts: 10
Likes: 0
From: Pennsylvania
Would a relearn clear a set up, I relearned the new tb an reset my ecu
Reply
Old Oct 6, 2018 | 05:15 PM
  #7  
ECaulk's Avatar
Senior Member
iTrader: (6)
 
Joined: 07-19-10
Posts: 26,529
Likes: 841
From: Houston, Texas
That seems about right for a stock pulley. If you replaced the cat its likely the other was failing and causing extra back pressure.
Reply
Old Oct 7, 2018 | 10:56 AM
  #8  
Jeremy Gardner's Avatar
Thread Starter
New Member
 
Joined: 12-22-17
Posts: 10
Likes: 0
From: Pennsylvania
I was at a meet last night an a guy with a laptop an a hptuner, we linked it an found a lot of cool **** out along with my low boost issue. Turns out I lost my pressure from the original stage 2 set up it had an went to stock after I relearned the tb. But we ended up putting a stage 4 Hahn 18psi file from off his lsj an holy **** the balts alive again
Reply
Old Oct 7, 2018 | 11:17 AM
  #9  
ECaulk's Avatar
Senior Member
iTrader: (6)
 
Joined: 07-19-10
Posts: 26,529
Likes: 841
From: Houston, Texas
You don't have a stock pulley then...
Reply
Old Oct 7, 2018 | 11:23 AM
  #10  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
What the hell is a Hahn stage 4 18psi file??? A stock pulley puts out 12-12.5. You do not have a stock pulley if you’re seeing 18psi. You can’t just turn boost up on a supercharged car.
Reply
Old Oct 8, 2018 | 05:05 AM
  #11  
Jeremy Gardner's Avatar
Thread Starter
New Member
 
Joined: 12-22-17
Posts: 10
Likes: 0
From: Pennsylvania
Originally Posted by chevygirl2006
What the hell is a Hahn stage 4 18psi file??? A stock pulley puts out 12-12.5. You do not have a stock pulley if you’re seeing 18psi. You can’t just turn boost up on a supercharged car.
his tune of his stage 4 lsj was on a flash drive. plugged it into his laptop I did rolls from various speeds an cruised around out of boost Idk how or what he did to it but my car is seeing 16-18psi at wot, 15psi as low as 2500rpm. But 3.0 pulley an some dude that has built LSJs for quite a few people said my boost actuator solenoid is aftermarket an that I’m running Lucas 42# injectors which I didn’t even know about haha Idk everything about these engines but I use what I’m told by these guys

This my build that’s getting the last of the bolt ones this winter, until I go rouge an upgrade the internals
Reply
Old Oct 8, 2018 | 07:10 PM
  #12  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
Pretty sure that’s a stock pulley. But either way something isn’t right. A tune doesn’t just increase boost
Reply
Old Oct 8, 2018 | 07:11 PM
  #13  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
And that boost actuator is stock...
Reply
Old Oct 9, 2018 | 08:16 AM
  #14  
jdbaugh1's Avatar
Senior Member
iTrader: (1)
 
Joined: 02-03-16
Posts: 6,435
Likes: 358
From: Kansas
Measure your pulley. It looks stock like other people are saying. As others have also said you can't just turn up the boost on a supercharged car with a tune. The boost pressure is determined by how fast your supercharger is spinning which is dependent on your pulley ratios. The bypass mechanism on a supercharger is different than a turbo and is only activated with reduced throttle and when the ECU decides something is wrong. Otherwise, if you are at WOT, you are getting all the supercharger can put out.

If you are making anything close to 18psi with what looks like a stock pulley then you are either getting false readings or your exhaust is severely restricted.
Reply
Old Oct 9, 2018 | 01:09 PM
  #15  
chevygirl2006's Avatar
Senior Member
 
Joined: 07-21-11
Posts: 10,937
Likes: 94
From: Texas
Boost depends on air flow
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jeremy Gardner
Problems/Service/Maintenance
3
Oct 8, 2018 05:17 AM
Drunkship
Problems/Service/Maintenance
2
Jun 16, 2015 02:39 AM
russell10x
Problems/Service/Maintenance
3
Dec 23, 2011 10:50 AM
teampruven
2.0L LSJ Performance Tech
2
Feb 1, 2010 12:30 PM
RedEcotecSS
2.0L LSJ Performance Tech
4
Mar 8, 2009 10:48 PM




All times are GMT -4. The time now is 09:13 AM.