getsideways

a friend of mine just put a mild 383 in his 1987 el camino with ccc. it runs pretty good with his stock computer which is a 1228079. i told him that iv heard of people putting monte ss computers in there el caminos becaus of a more aggresive timing curve. supposedly the monte used the same 1228079 computer. he bought one off ebay from someone parting out a 87 monte. he put it in and it doesnt seem to have any more power and the idle is all over the place. he had no idle issues with his computer. i was trying to look up the broadcast code on his new computer to verufy it came out of a monte but it has a 3 digit code of FYM. i cant find reference to 3 digit broadcast codes. everything is 4 digits. also his code from factory el camino computer is FYL. can anyone verify this computer he bought off ebay was in a l69 monte? or point me in the direction to find these 3 digit codes? thanks

RBob

iTrader: (1)

The information I have shows that they are both for the '87-'88 MY, LG4 305, 4-bbl, TH200-4R w/TCC, and California emissions.

The difference being that FYM is for a 3.73 rear ratio.

While the FYL is for a 3.08 rear.

RBob.

getsideways

thanks alot. i guess thats why he noticed no performance gain over his computer. so are these 3 digit codes specific to the lg4? and what codes should i be looking for to make sure its from an l69 engine? thanks again

JP86SS

iTrader: (1)

I have one (1227169) at home I can check for you later.
From an 86' SS but I'm pretty sure it was the same in 87.

I also have a LG4 logging definition that I made up but never got to test it. Sold the car before I could get it to work.
If you want I can send it over for you to confirm the connection codes and functionality. Needs a cable with a resitor in it to work with carbs IIRC.

Edit:
https://www.thirdgen.org/forums/diy-...-diagrams.html
From the guide book, CCC section.
Post 5 indicates CPY for 85 SS and another (unknown) BCC for an 88 file out there somewhere.
If you have a bin of the current, should be able to open the files and see what the diffs look like.

RBob

iTrader: (1)

The 3-letter BCC's are just from the earlier vehicles. There are even used in the '7747 TBI ECM among other TBI & TPI ECMs.

The one to get is ACFZ for the '8079 ECM. This is '87-'88 MY, Monte, L69, 4-bbl, TH200-4R w/TCC, 3.73 rear and Federal emissions. From what I've seen in the past between Fed & Cali emissions the Federal will have more aggressive spark advance tables.

RBob.

getsideways

thanks guys. i see one on ebay thats has a code ACFU. what does the u designate? gear ratio? the u is the only difference from what you recomended.

JP86SS

iTrader: (1)

Just checked it, I have a 1227169 that came out of my 86 Monte SS, It has "CFC" as the broadcast code on the sticker and on the chip.
Should be L69 with 3.42 rear, 2004R, w/ Lockup.
I have no lookup to be 100% sure that it was the original but with only 35k on the car when I got it, I'm pretty sure it was.

RBob

iTrader: (1)

The individual letters don't mean anything. It is the full BCC together that is used to define a particular calibration. BTW, that one is for an LG4.

RBob.

getsideways

we found a computer locally thats is ACFM. does anyone know what application this is for? is it an l69 aplication?

RBob

iTrader: (1)

'87 Caprice, LM1 5.7l engine, 700r4, fed.

RBob.