i just bought an 05 ss sc and realy tried it out for the first time last night on the highway. It made 100-103 kpa of boost. I made the math in my head then and it didnt make any sence. whats that 15 psi? Is that even possible for that stock blower pulley

 

if its an 05 it could have a clogged cat...

 

i doubt it only 50k km on it. u never know i just dont imagine that being the case. seems to stay around 12-12.5 then jumps to around 15 at 5000rpms

 

12 to 12.5 was max boost i'd get on stock pulley before i changed things.

 

I have an 05. Trust me.. it can happen..

First cat blew out at 28k. Second one at 52k..

Thats why i said something...

 

Not to thread jack but I think my car did the same thing yesterday. Raced a maxima and in second gear I hit high rpms and looked at my boost gauge I hit fifteen and then it kinda smelled like something was burning. I asked a guy at modified by kc and he said I probably just blew the tires out from under me and so my rpms jumped. My question is if you are running with a clogged cat is it harmful to your engine?

 

It can... its not something that is going to blow up your car next week.. but its something that should be taken care of asap..

Its going to really effect the performance of your car...

Right now it is clogged... people have experienced a loud "bang" after driving with it clogged, where the shot the insides out the tail pipe... the car will run HORRIBLY...

 

Agreed! Mine went out at 800 miles!

 

Yea hes lucky makin it as far as he did.. lol..

 

Here is an ANCIENT thread I made about the issue. It describes what the car was doing and others chime in on what's really wrong and such. Might take a look at that.

https://www.cobaltss.net/forums/problems-service-maintenance-69/catalytic-converter-out-600-miles-13636/

Ya, when mine did it stock it would make over 20 psi at altitude at 4-5k rpms! Then it would die around 5200 or so and its was so slow. Sad way to drive my brand new car!

Good luck to the OP, I'd suggest maybe getting a 3 inch (2.5 inch outlet) Down Pipe with Cat (Due to sound). OTTP sells a nice one for a reasonable price.