Ok guys, I bought an 06 cobalt ss/sc a while ago. I was told it was stock, I didnt know much about these cars so I didnt find out till later that the car had a 2.8 zzp pulley, which was the only upgrade...problem was the car was still running on stock injectors and no tune, scared that it might lean out on me I didnt beat on the car anymore. I bought a stock pulley and belt, I had the pulley changed back to stock. Now my problem right now is, before I changed the pulley i was able to hit close to 13 pounds of boost, now that the stock pulley is on I can only hit about 6-7 pounds, is this normal or should i still be able to hit around 10-12 lbs? Thanks.

 

Your car probably has exhaust work done to it along other stuff, take pictures of your exhaust setup from header to muffler along engine bay shots and some pictures of those injectors as well so we can better assist you.

 

E4 Photo by dtec921 | Photobucket here are pics...I'm pretty sure everythingss stock

 

And those pics are before I changed the pulley back to stock but nothing has been done to it since

 

didnt beat on it but with it only having a 2.8 and no other mods you went to 13#s of boost?

 

When the 2.8 was on I was able to push 12-13#s close to redline but stopped doing that because I found out that it was very dangerous considering I'm running a 2.8 without tunenor injectors, so I drove normally for a couple of months, and today I finally changed it to stock and I push like 7-8 pounds max close to redline.

 

That's pretty normal. I think I saw 10 one time when I was stock. I get to 15th on a cold non humid night with a 2.8, 60s, and a hp tune.

 

Yea as long as that's normal, I'm going to get zzp 3" intake sooon. And I want to delete the resonator, any suggestions?

 

I have a suggestion use the search button and post in the correct section

 

I am on my phone but I'll answer it in later if it hasn't been answered by then.

 

Should be 11.5 psi stock

You might have a clogged cat or bad boost bypass deal

 

I hir 17 psi max on stage II no other mods. Eveything is working fine.