Re: how do i increase pre-load on the wastegate spring?

[Robert Houk - WorkGroup Server Firmware <Robert.Houk@East.Sun.COM>]

   hey all, i want to increase the preload on my wastegate spring just a 
   little bit.  Its only boosting about 11.5 psi, and i want to bump it up a 
   couple psi, and im not quite sure how to do that.  

   anyone have a simple procedure?

Depending on your model . . . some wastegates are adjustable. There is
a hex (allen) bolt in the center of the wastegate cover, under a little
sticker/plate. Pry the plate off, and you can screw the allen-bolt in
and out and get "a few" PSI delta.

You can "bleed" manifold pressure back to the wastegate atmospheric
reference, but you gotta be careful not to do too much or you get a
positive feedback and blow your engine (expen$ive). Covered in much
detail in the archives. There are a lot of ways of doing this, from
rudimentary crude and cheap to Kilo$ electronic servo loops with 
incredible adjustment ability.

You can replace the wastegate spring with a stronger one (easy, and
reliable, but a nuisance if you want to try different values).

You will quickly run into ECU overboost shutoff, however, so you
really need a new "chip" to allow higher boost. The cost for this
ranges from free (my WEB page) to $500/$600/$700 commercially-avail-
able mods (IA, TAP, to name a few). Again, all covered in the
archives.

					-RDH