Insane1

What is the number of the stock ECM in my 85 Vette? Will WinALDL work with this ECM? Can this ECM be upgraded? Should it be upgraded? Will I get any improvements from an upgrade?

org502slow

what r u trying to do ? the 85 computer is very slow

-js-

That one is a 6870.
From the faq>What does my Corvette have?
The ECM/PCM for each year is as follows:

Years covered – ECM Part Number
1985 – 1226870
1986-1989 - 1227165
1990-1991 – 1227727
1992-1993 - 16159278
1994-1995 -16181333 or 16188051

Winadl will scan it http://winaldl.joby.se/aldldata.htm .

Muffin

You got the stock number. Will WinALDL work, Yes. Upgraded,If you mean swapped for a faster ECM ; Yes. Will you notice any better performance, Hard to say but there has been relativly little hacking of the 870 ECM and its associated software compared to the 165 ECM found in the 86-89 Vette plus several F-bodies. The swap is well documented here (see Bluevette85 postings). Not a bid progect and opens a world of opportunities for improved ECM/prom editing. If you want to get into prom edit and scanning the swap is almost a must.

MrNuke

Programming the '85 ECM is pretty simpe, and since it has less things to get messed up due to less lines of code and sensor input, it is a bit easier IMO than a newer chip/ECM.

Only draw-back of the system is, if you want to datalogg or see live data while driving.

0ski_dwn_it

Why do you want to change from the 85 ECM. Its more than capable of running your car VERY well upto and including some 600+ hp range when properly tuned.

Take a look at 85vet's 383 (low 11s) and Corkvette1's 434 (10.2x@131MPH) both running my tunes.

The 85 computer is probably one of the BEST ECMs for performance. It controls the spark and fuel as good as ANY ECM aftermarket (including DFI or FAST) or stock ECM. Furthermore it does not contain any of the garbage that many mistake for advantages such as fuel correction for air temps and O2 readings. ALL these cause major problems with running larger cams etc.

I would spend my other ways than changing out an ECM if I were you.

Insane1

Is there a manual out there someplace to teach how to adjust/tune the settings? I would like to try to change things to see what they do and stuff.

0ski_dwn_it

Lots and LOTS of reading on the scan and tune section and other sources of information.

Hooked on Vettes

http://www.thirdgen.org
DIY PROM message board

0ski_dwn_it

And take everything you read there with a grain of salt. 98% of those guys on that board that claim to be experts - have cars that can't get out of the way of themselves.

I know of only two guys on that board that truely can tune and get decent results - the rest of them "think" they know what they are doing and will be the first to tell you - once you start getting a hang of things things and start questioning their thoughts.

If you are the type of person that likes to follow, then you will fit in fine. However, if you like to think for yourself and try new things, then you will not be very liked.

Hooked on Vettes

Can you post some links besides this site or reading material, and what other sources of information are you refering to?

The Scan in Tune section on this board has little activity. In your opinion, how many knowledgeable people post on the Corvette Forum Scan and Tune board?

Since most of the people posting here have questions concerning the tuning of their own vehicle, do you share your tuning knowledge by specifically answering their technical questions posted here or does someone have to pay for your services?

0ski_dwn_it

I have written many things on different aspects of the tuning to help people out. Some in particular are how to tune: Startup tables, correct for idle blms on MAF, part throttle idle, 02 behavior / diagnosis, PE table changes.

Many I asked to become stickys, so they don't get lost in the archieves, but that did not happen.

I was not trying to be smart by saying LOTS of readings, but people telling you what to do is going to only crutch your learning. Its truely something you have to just start doing and work through the learning process.

JrRifleCoach

Ski, I been searching the archives and found a few of your posts. Lots of tuning data to read and absorb... then try.

Not trying to hijack this thread.....

GRX

[QUOTE=...The 85 computer is probably one of the BEST ECMs for performance. It controls the spark and fuel as good as ANY ECM aftermarket (including DFI or FAST) or stock ECM. Furthermore it does not contain any of the garbage that many mistake for advantages such as fuel correction for air temps and O2 readings. ALL these cause major problems with running larger cams etc.
I would spend my other ways than changing out an ECM if I were you. [/QUOTE]

THANK YOU!!! After years of reading people BASHING the '85 ECM finally it has been written.

0ski_dwn_it

[QUOTE=GRX]That is my honest opinion - it controls what you need it to very effectively and doesn't **** with stuff you don't want it to. Its SIMPLE and effective.

If it was a simple plug-in, I would be running one in my car.

Insane1

I have no clue what I am doing. I am just trying to get more out of my car then what it currently has. I have a 383 in another car that I am thinking about putting in this one and want to make sure the computer is up to the task. I have Ford 19# injectors in my car at the moment and I don't know if they are set up correctly and if they would work with the 383. I am going to put my cast iron heads that are ported and polished with oversize valves and my stock intake that will be polished.

B84RADR

Jesse, if you remember I had your help in programming a chip for my '85 in trade for a laptop. When I talked to you on the phone we had problems with Diacom+ reading the spark advance settings (always read zero). The best you were able to help me tune to was a 14.53 1/4.

After leaning out the gas properly and adjusting spark advance tables, my best ever was a 14.09. I have a pretty new 383 with a comp cams street/strip cam, Dart aluminum heads and a few other things. In my opinion, either I didn't get a good tune from you, or better yet, the 1985 ECM didn't handle the diagnostics at a decent enough baud rate (and was missing spark advance completely) to actually do enough analysis to get a decent tune.

Because of this I was enticed to go to an '89 165 ECM that has an output data rate of 8192 baud (instead of 600 baud for the '85 870, I believe), it workes with DataMaster and Diacom and it reads spark advance settings correctly. I'm getting ready to make the switch. I have everything ready to go, and I almost did it today. Now after reading this I'm wondering if this is the best thing to do.

This thing will do better than a 14.09 with a proper tune. It's still running pretty rough. It certainly doesn't feel like it has a good tune.

I could still use some help with this.

Thanks,
Shayne

rebuildman

Is there an upgrade chip to this computer (1985 6870) that does not require a UV light to erase it? That would be a EEPROM type chip correct?
If I read other posts correctly there is a problem trying to monitor data with a laptop on the 6870 compt?

B84RADR

There isn't an EEPROM available for the 6870, which is one more nice thing about going to the 165 ECM.

LD85

You cant go worng on going to the 165 ECM, obviously GM decided it was an improvement that lasted till 1989.

The 85 ECM lacks flexibility and only Corkvette as far as I know, has had success with it, ther could be others.

Ski's tune was probably as good as it gets, but I think you have a whole lot left on the table with your 383,,,,,, low 14's is ridiculous and high 12's very low 13's is more likely, depending on you cam specifics!

Your too far along to turn back now $$$$$$$$$$$$$$$$$$