[Diy_efi] ECM for 1990 Nissan 240

[J]

>>Anyone have suggestions for which GM ecu to use?

I personally like the '7730 ECM.  It was used in a dozen or more factory 
applications, so it can easily be found at a junkyard, it came stock on 2.0L 
4-cylinders in the Beretta's, Corsica's, and Tempest's (possibly others as 
well) so you know it's 4-cyl compatible, and it uses an easily removable 
memcal.  It was also used in V8 applications (90-92 Camaro/Firebird TPI) and 
can be used on a boosted application with the $58 Syclone code with a few 
moved wires, which means it'll be fairly easy to upgrade your powerplant in 
the future.  It runs the higher-speed 8192 baud ALDL communications which 
makes datalogging much more efficient, and there's also a HUGE amount of 
support for tuning with this ECM, as the F-body guys don't like to leave 
cars stock.

The only thing that I'm not sure of is this:  I believe the '7730 
4-cylinders were DIS cars.  Don't quote me though because I'm not sure.  The 
'7730 was used on dizzy-fired applications as well, but the stock 4-cyl code 
might require some tweaking to run a dizzy ignition.  One way or the other, 
the GM ignition setups all use the same timing signals anyway (regardless of 
DIS or dizzy hardware,) they just have different limits set in the code 
depending on which system was used.  Do some searching in the DIY-PROM forum 
at thirdgen.org for more specific info.