Could it be a partially plugged vaccum line or a weak one collapsing shut at full vac pressure.

 

I CHECKED THEM ALL AND THERE WHERE NO LINES SUSPECT TO WEAKENING ISSUES?
I ALSO REROUTED ALL HOUSES SO THERE WHERE NO ABRUPT KINKS OR BENDS!

 

my 2.79 is boosting as if I had the normal stage 2 3in pulley I use to boost 17 with it..could it be the huge hole in my exhaust after the resonator

 

knock to a degree can reduce the boost level to try and get of the kr.

shitty fuel.

someone set up the supercharger settings wrong in hpt.

 

I use shell I'm ganna start using mobile or sunoco..still I'm l
oosing alot of boost. The hole on my exhaust? My #42 its gatta be something

 

IF YOU HAVE A VACUME CAP PULL THE VACUME TUBE OFF THE UPPER PORTION OF THE ACTUATOR THATS ROUTES TO THE OUTPUT OF THE BOOST CONTROL CYLINOID VALVE (FRONT, FACING YOU) THEN CAP OFF THE OUT PUT OF THE BOOST CONTROL CYLINOID VALVE AND LEAVE THE TOP OF THE ACTUATOR OPEN TO ATMOSHPERE! TRY A PULL LIKE THIS IF THIS CURES YOUR PROBLEM THEN YOUR IN THE SAME BOAT AS ME?

 

fixed my exhaust still loosing 2 psi

 

ok im not "mechanically inclined" but i like to hit 200km in fourth gear just like the rest of you, so for all the techies out there riddle me this, why does my exhaust (vibrant cat back loudmouth) have so much re verb almost to the point of sounding like a backfire or even like a srt 4, i have a k&n tyfoon, stage 2 kit and the cat back system i have no noticible lack of power but when i hold the pedal steady at about 3000 or 4000rpm and then let go she pops and bangs as she winds down WTF is going on is that normal, do i need more compression better fuel or a new chevy any takers, i will truley appreciate any advice that i get thanx

 

I thought the more open you make your exhaust the more you will lose boost cause it opens the out go flow so the charger doesnt have to work so hard? (not directed at the guy with no boost)

 

The poping and banging is fuel igniting in the exhaust pipe.
Could be that when you let off the gas so quickly the spark turns off and the injectors are still putting out some gas and its igniting in the exhaust.
Or the valve timing is so advanced that it when you let off quickly the exhaust vales are still slightly open when the gas is ignited in the cylinder when you winding down.

 

that makes sense... sort of, it would definately explain carbon build up around exhaust tip , so is that popping and banging bad, good or niether, what could i do to stop it from doing that, mabey a header? it sounds like a srt 4 neon all garggly and throaty it sets off carr alarms 100 feet away and wakes my neighbors up in the mornings ha ha

 

and this is bad why??? all of our cars pop and gargle with an aftermarket exhaust

 

If its in your exhaust I believe it means your running pretty rich.

 

I dont have any troubles with 5th gear but sometimes it is hard to put into Reverse. Is that the Syncros you refered to earlier?

 

i never had exhaust on any of my cars before, i went out w some guys last night and they said it sound good, so i guess its not that bad, i just want to tighten it up a bit and im sick of cleaning and replacing my exhast tip all the time. if im running to rich how would i solve that, any way i love the way it scares the **** out of little old ladys on their power chairs, oh and my neighbors love it to

if your having problems putting it into reverse let out the clutch a bit, same for first, i dont know if its supposed to work that way, but it works, at least it should

 

I SHOULDENT HAVE TO THE CAR IS NEW AND ONLY HAS 14,OOO MILES?

 

ya i know, i have the same problem and lakewood and southpark gm couldnt diagnose a cold, nice ride though mine is the same color and g85

 

Clutch pedal vibrates after hard acceleration! I have talked to a lot of people who have that problem with the SS/SC. Also engine ticking during startup for about 1 minute.

 

THE TICKING IS THE INDICATION THAT YOUR CAT HAS SLIGHT MOISTURE DURING START-UP AND IS STEAMING IN CAT CAUSING A POPING NOISE UNTILL IT EVAPS.

I WENT TO DYNO AT BMG FOR COBALT MEET ON SATURDAY I DYNO'D 239WHP AND
198FTB WITH NO TUNE, STOCK PULLEY, STOCK INJECTORS. I PORTED AND POLISHED MY SUPERCHARGER AND I INSTALLED A PACESETTER LONG TUBE 1.75 PRY HEADER AND BUILT CUSTUME DOWNPIPE CATLESS WITH FLOWMASTER 40 SERIES EXHAUST. NOT BAD #'S THIS SAT COMING UP FRED AT BMG IS GOING TO INSTALL MY 2.7 ALONG WITH 60LB INJ AND I PUT IN METH INJ AND DUAL PASS WITH BIG FRONT MOUNT. WITH AN AGRESSIVE TUNE I'LL HIT 300WHP/TRQ. I'LL KEEP YOU POSTED!

I'VE SPENT A TOTAL OF 450 DOLLARS! AND GAINED 100HP/TRQ!!!

 

you won't hit 300

 

[SIZE="4"][COLOR="DarkOrange"]Your right the car wont go past 3500 rpms with out the ecu putting it in protection and all my timing goes away along with my horse power? Before 3500 rpms I made 258ft of trq and 260hp at the wheels! SO YOU DO THE MATH JUST REMEMBER I HAVE A PORTED AND POLISHED SUPERCHARGER AND A METH KIT ALOND WITH A GOOD TUNE!!!!