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Re: newby

Andrew Plunkett wrote:
> 
> > >>> a couple 1227748 "G" ECMs.
> 
> What advantages does the 747 have to a 748?  Isn't the 748 for V8?

The '748 is for 4-cyl engines with a single injector TBI unit.  The '747
is for V6's and V8's with a dual injector TBI.  The '748 is newer
technology - it has a 8192 baud serial link while the '747 is 160 baud. 
Both are transmit only though.  The '748 has a hard wired limp-home
calibration while in the '747 it is changeable.  Interestingly, the '748
was used on three different sized engines (2.0, 2.2 and 2.5) from two
different families.  GM must have sized the TBI to match the displacement.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/
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