More Questions. now on 94 p/u

[EFISYSTEMS at aol.com]

Hi Mike,
       When you remove the glove box ( 4 -7mm or 9/32 screws ) your pcm will 
be on the right.  It should have a red connector and a blue connector,  this 
will not interchange with the 747 as your computer also controlls the 
transmission.  
        This computer uses a 27512 chip and has two main fuel tables and two 
main spark tables both set to switch to the secondary at 3% Tps and roughly 3 
mph(this can be adjusted) There is also a very fine grain low rpm fuel table 
0-1600 rpm in 100 rpm increments and 5 kpa increments....Lots of trans stuff 
and much more engine stuff than I have stated...If my memory serves me 
correctly it uses 2 68hc11 processors.( I could be wrong though) 
        When you were on the dyno I am assuming no computer was installed and 
it had headers and now in the vehicle is all stock????  If you can get me the 
cam specs and all other mods I might have done something similar and can get 
you a head start on a .bin file or send you a memcal...but to truly fine tune 
it you are going to want to have your own burner and erasure and lots of 
time.....let me know.
-Carl Summers


In a message dated 10/25/99 7:03:42 AM Pacific Daylight Time, 
mrolica at meridian-mag.com writes:

<< Subj:     More Questions. now on 94 p/u
 Date:  10/25/99 7:03:42 AM Pacific Daylight Time
 From:  mrolica at meridian-mag.com (Mike Rolica)
 Sender:    owner-gmecm at esl.eng.ohio-state.edu
 Reply-to:  gmecm at efi332.eng.ohio-state.edu
 To:    gmecm at efi332.eng.ohio-state.edu (Gmecm (E-mail))
 
 A while back I got the motor on my old mans pickup rebuilt.  It is a 94 Fs
 GMC ¾ ton 4x4 Ext cab shortbox.  It has  350 tbi 4spd (60L4E I think) 16"
 tires ect ect.
 He does a lot of towing as he has a farm on the side, A 20' 2 axle cattle
 trailer- about 11 tons most of the time.  He goes to Denver col. Every year,
 new york, ect. Ect at 200 000km the motor started to knock when it was
 cold., burn oil ect.
 
 We rebuilt the motor using Isky custom sing pattern cam, 265 adv., 450 lift
 (I think, it's around there)  I did some work to the heads :-) gottem swirl
 chamber buggers to flow a little better (80%)  which is the reason for the
 single pattern cam.  Used hyperutectic flattops, decked block to .005 in the
 hole.  Runs about 10.5:1.  On the dyno it ran awesome, used a Oval track
 distributor some 104 oct and a 2bbl Rochester also used for oval track with
 an adapter plate  made up.  Plate was kinda crude as intake bores were a bit
 out compared to the carb.  Motor made 300hp, 405ft-lbs.
 
 Now in the truck runs like crap!
 Before, the truck ran rough at idle (shook), smelled like rotten eggs some
 times. Now it is worse.  Also sound like a diesel when cold until goes into
 closed loop,
 Would appreciate it if some people could give me info on the following:
 *  Ecm/pcm type number
 *  Type of prom
 *  Suggested mod to programming for new motor and the application of
 the truck
 *  Links to anyone having experience on this ECM
 *  What to do
 *  Any suggestions
 *  Bruce? Any comments
 *  Please
 *  Hacks
 *  Where to look
 Mike Rolica
 EXT. 260
  :-)
 
  >>