Part of the problem, as I see it, is that I doubt that many factory turbo
cars list the "stock boost level" or even a range, anywhere in the service
manual. They may be advertised, but I don't think that they are listed in
the service manual. I do not think that it is anywhere in the STi service
manual, for instance. Which is probably why the current rule relies on
modifying the SYSTEM instead of regulating the LEVEL. And the STi has a
little problem with boost creep with the stock turbo and most aftermarket
downpipes, to the point where you will hit fuel cut. You could run a
manual boost controller, but that, of course is not allowed, even if it is
set to "stock levels", and is in place only to restrict the boost creep. I
am not familiar with the SP rules, but it may be possible to swap in a
slightly higher flowing turbo which, when regulated by the stock computer,
may a provide denser (cooler) charge than the stock turbo. Of course, too
large and you have to deal with lag......
Bob (AX newb) Christensen
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