Chevy86 IROC-Z

iTrader: (17)

Another question guys. Which IROC-Z PROM's are interchangable with a 1987 350 TPI IROC-Z? In other words, what other years of IROC's had the same interchangeable PROM's?

305sbc

iTrader: (3)

If you have what I have, then most of them from 1986 through 1989 interchange. For TPI, the important factors for the mask are engine size, transmission type, and rear gear ratio. Corvettes also used a different mask.
My PROMS from my 86 and 89 are swappable.

Chevy86 IROC-Z

iTrader: (17)

Thanks bro. So then I can get any IROC 350 PROM between the years of 86 - 89, actually 87-89 because 86 only had 305's. There were about 50 350's in 1986, but from other sources, they never hit the market.

RBob

iTrader: (1)

If you are looking for a drop in stock GM PROM, stick with the '87 and '88 f-bodys. In '89 they had VATS which will prevent the engine from firing.

RBob.

305sbc

iTrader: (3)

I assumed that your question was just about the EPROM itself and not an exact code swap as well. I thought you would be using your own mask and calibration.
Like Rbob said, you'd need to have the mask match in order to have just a drop-in replacement without a re-burn.

Chevy86 IROC-Z

iTrader: (17)

Uhhh... You see here is my issue. My IROC is a 86. 86 only had 305's. I slapped in a 350. Come to find out, my IROC already had a 350. When I got curious about the PROM, I later learned it was a 305 PROM (DELCO AMU 8958). My bro n law gave me his 87 350 IROC-Z PROM (Hypertech 127062) which was perfect because this Hypertech PROM was made only for the 87 IROC. So now I got a code 51. I went to Autozone and bought a Cardone Reman ECM. I tested it out and bang,, code 51. I took the Reman ECM back and claimed a faulty Reman ECM so they replaced it for free. Now that I got an other Cardone reman ECM, I tested that one too. BANG!!!!!!! Agian, code 51. This was all with the Hypertech PROM. So now I know the PROM is bad. So now Im on a hunt to find a 1987-88 350 TPI IROC-Z OEM PROM so that I can ride correctly. Plus it's cheaper.

RBob

iTrader: (1)

I'm confused, in this thread:

https://www.thirdgen.org/forums/diy-...om-delete.html

You mention disabling items in the calibration. If you are doing that then the 305 MEMCAL can be used. Best bet is to head over to Davis's site and grab a stock '87 5.7l calibration that matches the car as close as possible (TCC lock up varies with rear gear).

Make the changes you need, and burn it into a PROM. Install and turn key.

RBob.

86ttopbird

Why not just get yourself a $40 eeprom programmer and a couple chips, go on moate's site, download the 350 IROC code mask bin and burn yourself a new one. It is not hard at all and theres a TON of write ups on this forum about how to do it properly. Theres a couple of gurus that frequent these boards and they may even have the bin already.

Chevy86 IROC-Z

iTrader: (17)

I understand your confusion. I asked about the EGR and SMOG so that I can be informed prior to making a final decision, which would be to reprogram my 86 OEM 305 chip, or just find a OEM 350 chip.

Chevy86 IROC-Z

iTrader: (17)

I just got out of the moates website and I looked for the 350 IROC-Z mask bin and had no luck. Do you have a suggestion on which EEPROM programmer should I get aswell as provide me a link to the 350 mask bin?
Thanks.

86ttopbird

The one i got was the $40 dual power willem programmer from www.mcumall.com. The chips are $2.00 a piece. If you search the "v6 owners take a look" thread, it tells you how to remove the old eprom chip and put in the new one. Yes its for V6 owners but the eprom removal and replacement is the same for V8 cars. As for the proper bin, it depends heavily on your transmission,rear gear ratio, engine size, whether or not its mass air or speed density, etc. I dont know these things but i am positive if you ask Rbob or bl85, one of them might know for sure. But if your car is mass air, i can say its either $32B or $6E code mask. Without knowing for sure what your car is equipped with, its a hard call to make. But your car being an 86, it would have the 1227165 ECM. If for some reason its speed density, it would be the 1227737 ECM. Take a look at your old PROM. Post back here the codes on it. There should be a series of letters and numbers in the codes. They Hypertech PROM may not have this on it.

Chevy86 IROC-Z

iTrader: (17)

Inside the window on the OEM PROM it reads "DELCO AMU 8958." I did a search to verify the PROM and I found that it is indeed for a 86 IROC. On the side of the PROM housing, the are numbers that read as follows, "16035006 8604.". Also when I got a rebuilt 700R4, the tranny company told me that the tranny is from a 87 Vette. Is there a casting number on the tranny case that I can use to verify what type of tranny I have?

Chevy86 IROC-Z

iTrader: (17)

Is this what you got?

Chevy86 IROC-Z

iTrader: (17)

86ttopbird- my OEM PROM is the 86 IROC Z 305 PROM . Here is the info on the PROM-----
BCC used in 1986.
BCC= AMU 8958 Scan id= 9461 Part number= 16058955
Release date= 07/18/85 Engine size= 5.0 Trans Type= Auto trans
ECM/PCM: ECM #01227165

Chevy86 IROC-Z

iTrader: (17)

Another thing. Are both these PROM's for the 1987 350 TPI IROC Z PROMs the same?

86ttopbird

ABWT i believe is a revised ABWN code. If you have 3:27 gears, it should work just fine. Being that they are from a 1987, they should be mass air PROMs as speed density wasnt phased in until i believe 90 or 91. And yes that is the exact programmer I got. It should be around $49 or so. And a 305 PROM will not run a 350 too well. The fueling in and of itself is not enough for a 350. The timing tables are different as well. You really need a 350 PROM or bin if you program one for yourself.

Chevy86 IROC-Z

iTrader: (17)

Cool. Thanks for the info 86ttopbird. Ill see you around in the boards.