boost issues

[ReliantK]

I've redone all the vacuum lines on my glhs charger using a vacuum block, not using the boost control solenoid and I'm using a manual boost controller [the "home depot" MBC] to control boost.

I have MP stage 2 14-psi computer and right now I'm only getting 10psi in first gear, 12 psi in second gear, and then in 3rd gear I'm finally getting 14psi.

why am I not getting 14psi in 1st and 2nd gear? or is this normal?

and also when the car gets into boost the lights dim a lot....

no codes from the computer, I'm gonna go out and check voltage at idle, car also has a new battery in it.

edit: at idle voltage at the battery is 14.15 volts

[mpgmike]

First, the MP computer cannot deliver 14 # boost if you take away it's controls. You need to reconnect the wg sol for the MP Comp to control boost. Check to see if your wastegate door isn't sticking open just a tad, bleeding off exhaust. You might be able to spool up quicker and to your desired boost setting by adding a bov. Check belt tension to alt. It might be slipping at higher rpms.

mpgmike
'88 Shelby Daytona
'91 Spirit R/T
'84 Rampage

[ReliantK]

I'm using a boost controller in between the wastegate line and vacuum block, shouldn't that not make a difference because I'm now controlling the boost with the boost controller and not the computer?

also how do I go about checking to see if the wastegate door is opened partially?

thanks for the help

[ReliantK]

anyone? any help is appreciated

[ReliantK]

[mpgmike]

Quote:

Originally Posted by ReliantK I'm using a boost controller in between the wastegate line and vacuum block, shouldn't that not make a difference because I'm now controlling the boost with the boost controller and not the computer? also how do I go about checking to see if the wastegate door is opened partially? thanks for the help

I would use one or the other, but not both. Either run directly from the turbo or intake manifold, through the boost controller, to the wastegate, or let the MP computer control the boost through the stock wastegate solonoid.

There is a small clip that holds the wastegate actuator arm on the wastegate. Remove that clip with a pocket screwdriver and see if the wastegate is sticking, binding, rusted, or whatever. If it moves freely and you can feel it positively stop when closed, it should be OK.

mpgmike
'88 Daytona Shelby
'91 Spirit R/T
'84 Rampage

[ReliantK]

well I think I found the problem, I took apart the boost controller and the spring I'm using inside is wayyy too flimsy and starts binding up when you adjust the controller for more boost. Arg!!!
tonight I was only getting 10psi and the car still feels fast, can't wait to take advantage of the full 14psi!!

[mpgmike]

Congrats my man!

mpgmike
'88 Daytona Shelby
'91 Spirit R/T
'84 Rampage