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Re: gm altenators...and efi



> now for the efi.... As the voltage got lower.. it started running
> fatter and fatter, till it started missing ( have msd and good coil) I
> think this is due to the bat voltage vs injector offset..... also idle
 >went up 300rpm....
> Is there something in the code to kick idle up if voltage drops below a
> value???....

I am going to guess that the MSD can only do so much with such a voltage
drop, obviously weak spark and same amount of fuel will load up an engine.
Batt volts vrs injector offset is there to try to compensate but getting
only 8 volts is close to ECM shutdown ;-).

Yes, as the voltage drops below a certain point, the ECM will raise the rpms
to try to compensate, till you get home and fix the problem, hopefully.

Iceberg sells a conversion for GM alternators that replaces the rear housing
with one with cooling fins cast in at the back side where the rec/reg
reside, and also has a larger hole for their larger high temp bearing, along
with a phenolic spacer for the bearing.  Nice to see all the areas of
weaknesses addressed with these alt upgrades.

Jeff M










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