I have not added the chip yet.
 I wanted to add the modifications to my engine before the chip to see if I
would need the chip.  After running the modifications for 26,000 miles, while
they run good, I think that the chip will enhance what  Ihave done.
 I think that On a stock engine, unless the chip changes your current driving
habits, there should not be a change for the worse in mileage.  The engine
will still be running at the correct ratio, but will be able to run better.
 I have raised my mileage from 18 mph to @25 mpg on flat to moderately hilly
@75 mph while increasing my power. In the engine, I changed only the cam to a
slightly bigger lift and duration increase and added ratio rockers.  The rest
is basically stock.
 I have been in email contact with the designer of the chip and thay have
been using it in their delivery vanagon for about 6 years now with no
troubles.

 Robert

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