Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Supercharged Vt Commodore lacking in power

simmo_91

New Member
Joined
Jan 17, 2011
Messages
2
Reaction score
0
Points
0
Location
Melbourne
Members Ride
1999 Vt Calais Supercharged
Hi my name is Simon and i have a 1999 Vt Calais Supercharged i have extractors and exhaust, cams and a 10psi Pulley Upgrade. My car seems to lag for a good couple of seconds when i put my fut down before any power kicks in and its only boosting at about 5psi. Does anyone know what this could be? Any help would be great thanks.
 

10WVN

New Member
Joined
Sep 21, 2009
Messages
99
Reaction score
0
Points
0
Location
Hervey Bay, QLD
Members Ride
98 VT s pac
could be a few things, air leak somewhere maybe hence the low psi *just a guess*

could also check all the spark plugs and leads, and maybe a service ie. new oil and oil filter, fuel filter and air filter
 

cander24

New Member
Joined
Aug 26, 2008
Messages
992
Reaction score
9
Points
0
Location
NSW South Coast
Members Ride
VZ GTO. VS LS1.
Depending on the cam specs, this has likely dropped your boost by a couple of psi, but you should still be seeing a bit more than 5psi. Everything in good working condition on a stock l67 should see about 5-6psi. My guess is your boost control solenoid is faulty. They are notorious for developing this fault and robbing you of boost as they can prevent the boost bypass butterfly from fully closing (full boost). You can either replace the solenoid, or bypass it.
 

Decicrate

Member
Joined
Sep 10, 2007
Messages
777
Reaction score
23
Points
18
Location
BrisVagus
Members Ride
VS L67
As cander24 said, check the boost bypass solenoid on the back of the passenger side head. Most people disconnect this. I would also be checking your engine mounts.
The L67's love to eat engine mounts, as they wear the pin that goes through the bottom of the mount starts to wear on the K Frame which in turn sets off the knock sensors and the ECU/PCM then starts to pull bucket loads of ignition timing out.
Next problem is that if you have installed CAMS you may have one too many, joke.
You may also want to double check the cam installation, you may have set it up with too much advance or even too much retardation.

The best site to get great information on the l67 is L67torque dot com
 
Last edited:

simmo_91

New Member
Joined
Jan 17, 2011
Messages
2
Reaction score
0
Points
0
Location
Melbourne
Members Ride
1999 Vt Calais Supercharged
When i bought the car it already had the extractors and exhaust, cams and the pulley. I havnt done any mods to it i have only serviced it and replaced spark plugs, spark plug leads, coil pack and got the transmission fully reconditioned with a stage 2 shift kit. Can anyone give me a tip on how to disconnect the boost bypass solenoid ill give that a shot. Another thing is my car when it is cold boosts at about 10 psi and seems to run a lot better but as soon as it gets to operating temp it starts to lag. Thanks
 

cander24

New Member
Joined
Aug 26, 2008
Messages
992
Reaction score
9
Points
0
Location
NSW South Coast
Members Ride
VZ GTO. VS LS1.
The best site to get great information on the l67 is L67torque dot com
Simmo_91, check out this forum. There's a great wealth of knowledge there specific to the L67. In the tech section there, there's a how to on this.
Cheers
 
Top