Need help from Turbo gurus

[THEEARTHGUY at cs.com]

I have 2 cars, an 86 4kq and an 87 Subaru Turbowagon.  On my wagon, the boost 
is set somewhere around 7psi, which really doesn't do the job.  A guy told me 
I could pinch down the wastegate vacuum hose a bit, so I did.  Now, my turbo 
is really moving the car!  Unfortunately, if I give it full throttle, it 
blows massive unburned crap out the back with a lot of pinging.  If I give it 
half throttle, the turbo spools up nicely to it's peak and fires the car down 
those onramps.  Is there anything I can do to get, say...9 or 10 psi without 
all the problems?  I don't think the wastegate has a replaceable spring...

Chris
Theearthguy at cs.com