Turbo HELP!!!

[TurboV6Olds]

I'm another newbie. I have a Cutlass with a newly implanted 87 GN drivetrain. I am trying to tune the car and having trouble with the boost pressure. I have a Auto Meter Cobalt 45 psi boost gauge with 30 psi vacum, manual boost controller mounted within 18" of turbo and wastegate. I can turn the boost controller all the way down and still get around 21 psi boost. Does the flow of air thru the controller make a difference? I have turned both directions and it does not seem to make a difference. Could the wastegate be an issue? I am trying to tune the car on low boost but cannot get it. Also having issues with o2 readings (too lean) Have LS1 maf and translator, scanmaster, razor alky, TT chip. I have added 17% fuel thru TT chip and still running 730 o2. Any help would be GREATLY appreciated.

Thanks, Rick

 

[SCOOBY DOO]

For the time being, disconnect the manual boost controller and go back to stock. Adjust the wastegate actuator to the point where you have to pull it about 1/8th of an inch to get it over the puck arm...this should give you about 18 PSI of boost...give or take a little...with the assumption you have an adjustable actuator. Check and clean all of your grounds...especially the ones on the back of the PS head...one or more of them is likely giving you the low 02 readings. There's another ground on the firewall and the one on the PS fender...and reset your chip back to the default settings.

 

[TurboV6Olds]

Thanks for the input. I will try what you said. I recently had to replace the head gaskets due to something I will not get into and remember connecting the grounds well to the ps head but did not pay attention how well it was connected to the firewall. I assume grounding is VERY important on these cars. As for the wastegate I have nothing to adjust. I only have two lines that come from the wastegate. One comes from the bottom to the controller and the other goes to the T where it goes to the other side of the controller and the turbo. Not sure what kind of wastegate I have, it was bought already installed on the downpipe. I have the car at my buddys garage or I would take a look now. I don't remember any adjusting like on a stock one. Thanks again, Rick