Reduced power and Reduced turbo boost

[Jay Darst]

Just returned from a 876 mile round trip to Elkhart Lake, WI.

Noticed the fuel vacuum gage in the red. So changed Racor fuel
before heading back home. Still the gage read in the RED. So, 1/3 of
the way home, changed the spin on fuel filter. Still the gage read
in the RED.

The gage seems to have always worked before.

Before and after changing the Racor filter and subsequently the spin
on fuel filer, my boost gage would see 20psi.

Later, when almost home(and dead dog tired) seemed that power was
less than normal and boost would only see 15psi.

The last tank of fuel was treated with Lucas fuel treatment, 1
gallon Lucas to 300 gallons of fuel.

Any suggestions as to why the loss of power and boost with fresh
filters?

Thanks
Jay Darst
85PT40 6V92 Detroit
Springfield, IL