I'm completely new at this, and I've been reading up a bit but I'm still real foggy on how to go about this. Here's the situation:

I have a nearly completed 383ci motor topped with a modded LT1 intake about ready to drop into the car within the next week. I really want to give the computer the first spot of attention on startup though. I have a few questions:

What software am I looking at for the whole tuning and burning process for an 85 comp, (stock for LB9 aith auto)? I've heard somewhere that tuning on the 85 is a whole new ball game, but I'm not completely sure.

Are there any tutorials on how to go about doing this, for both the initial start up and for later tuning?

Are there any steps I should take tuning-wise to make it at least safe for the engine to run after start up, not necessarily for performance but just to make sure it doesn't lean out, or does it make any difference?


Thanks for any help you guys can give. I have no idea why I'm still so lost here.

 

If I were you, I think I would switch to either the '86-'89 ECM #1227165 for MAF or the '90-'92 1227730 ECM for speed density. There's a lot more info available on these systems. If your current LB9 is still running you could use it for a test mule to get whichever ECM swap you choose working before you drop the new motor in. Of course that's just my opinion, YMMV

 

So there is no way to help the 85 ecm without shelling out the money for a new ecm? from what I understand, I'd have to buy the ecm and THEN tuning software, and then still have to worry about the repinning and such. There are no means to burn the chip for what I have?
By the way, do I have the 165, or is that something else?

 

If your '85 is all original it will not have the 1227165 computer. I really don't think there's much available for that ECM as it is a completely different animal from the '86-'89 ECM, however that '85 ECM isn't one that I have done much research on. It is possible that someone here may know about it, but from what I've read, it is altogether different. You should first check to see for sure which ECM you actually have. The part # should be on a sticker on the case of it.

As far as swapping over to the '165 ECM I don't really think it's that hard to do, and for the best results with your new setup, yes you will need to learn to tune your own chips anyway. There is free tuning software available. I use the TunerPro free version for editing my chips. If you go with the 1227165 with that LT1 manifold you will need to use the later code which eliminates the cold start injector.

Again, I haven't focused any research to speak of on that 1985 model ECM so someone else may be able to help you more, I'm just saying what I think I would do in your situation.

 

Actually I think since I have the car all apart I'm going to go get down to the ecm today. I'll check the sticker on it. If the car was made in the later half of 85 it should have the 1227165 p/n, right?
Well, with my fingers crossed, I guess I'll go check it out now.

 

..........doubt it. I started out with the 85 ECM (870), upgraded to the 165 ECM and then upgraded again to the 730 ECM. Repinning is not hard at all. You'll have to buy software, no matter what the ECM type. Do the right thing and switch ECMs! Feel free to ask questions or for advice. I'll even walk you through the process.

 

That would be awesome, actually. I've spent the whole day reading up on the actual process of converting through ecms, visited davis' site and printed out all the instructions and diagrams.
I'm thinking about doing this..just need to go out and buy the stuff. From what I understand, what I should do is go to the local junkyard and grab an 86-89 ecm w/ memcal, along with a couple relays? Which ones and how many do I need exactly?

 

I didn't add any relays. Just splice into the 5 volt TPS wire, use the MAF signal wire and MAF ground wire for the MAP and you are done under the hood. You'll need one additional ecm connector. They are usually green or yellow at the junk yard (You will not need any wires, just the connector). This is because the 730 uses 3 ecm connectors from the engine harness. Then just repin the connectors, clip in the ECM/memcal and you are done. The hardest part is to not damage a wire terminal or keeping track of what wires you already repinned ( knowing wire colors helps alot). If you are carefull then it should go just fine!

EDIT:that's provided you go with the 730/MAP system. IMO, the 730 is the only way to go. The 165 ecm swap will require you to relocate the maf burnoff relay and repin the existing ecm connectors, IIRC.

 

So you can go straight to 730 from the 870? I read that you have to go through 165 first, but this is alright too. What are the differences in repinning the 165 vs. 730? Is there a list somewhere of what is replaced with what for that particular swap?
I suppose what I go to depends on what the salvage yard has tomorrow. If the swap to 730 is so much easier I guess I'll go to that.

I appreciate the help, by the way

 

Forget that you heard of the 165 You'll need a speed density ECM+memcal/chip, extra ECM connector and a map sensor+connector. I like to grab the 3 ecm connector with the 730, then you'll always have the wires in a connector(and save some time, trust me). Swapping to the 730 is alot less work than goint to the 165. I don't think there is a sheet that'll show the 870 >730 pinout. You'll just have to use this...(85 wiring diagrams) right click save
Now that you know the 85 pins, you'll just need to swap them to the 730. There is a couple way to do this,
1) Grab the 165>730 document from the davis web site. Then replace the 165 pins with the 870's. Now you have the unofficial 870>730 doc . Do that and it's a cakewalk.
2) Just manually go through it, pin by pin. For example, find out where the coolant temp pin is on the 870 and 730, then remove the CTS wire from the 870 clip and install it to the correct pin on the 730. Do that for each wire.

LMK if you need any help. Since you are so willing to do this right, I'll even offer a phone call IF you get stuck and need some quick advice.

 

Why couldn't he just yank the whole engine wiring harness from a '730 f-body and replace his stock one with it? Then he wouldn't have to do all the repinning, that is if it would work. It may be more trouble than it's worth, or maybe not? I've been considering looking into doing this for my '87, which I have already changed to a '730 by repinning the existing '165 harness. It's just a random thought but I can't imagine why it wouldn't work.

 

It takes alot less time to repin than replace the harness. Besides, 99% of the time a boneyard 730 is not getting pulled from an f-body

 

It's probably true that more of the '90-'92 TPI f bodies are still on the road and better kept than the earlier years, thus making harnesses harder to find, but they can be found. None of the '730 ECMs I have came from an f body and the repin I did works fine. . I was just thinking that it might be another option if one were so inclined. I'm thinking about it because I'm using a crank trigger and an eDist and thought that I might customize the harness for my extra hardware before I put it in the car. This would also give one a chance to go through the harness and check all the wires and do any repairs needed while it was out of the car

305PhoenixAM, whatever route you decide on take comfort in the fact that many have gone before you and there is plenty of help available here.

 

I agree, It's just faster to repin if you already have an existing maf harness on the car. If one is converting to TPI, then by all means find a 730 harness. I have been through my harness a few times. IMO, it's a good idea to pull all the loom off and get fresh stuff (while checking the harness). My harness has been totally rerouted to create a cleaner engine bay......

 

So hypothetically, if I were to go about the 730 swap, then I have to also grab a '730 MAP sensor and the connector that plugs into it?
Just making sure. I think I'm good on everything else. Provided that the salvage yard is open tomorrow, I'm going to go see what I can find.



What other vehicles should I look for, for a good '730 ECM? If I pulled the '730 and I needed another MAP sensor and connector Im going to still have to find one from a 90-92 F-body, correct? Unless I were to go to a parts store or something...not sure how much they'd want there.

 

There is a list of the ECM numbers and the cars they can be found on in the Technical Articles section on this site. Most any GM MAP sensor you find that is used in conjunction with a 1227730 will work. Also, the TBI MAPs will work. You will need to get the ECM plugs and about a foot of the harness with your ECM along with the MAP plug. A new MAP sensor is about $30.00.

 

Salvage yard wasn't open today. Ah well, I'll look tomorrow. Just as well, I got some more questions. Sorry if its getting redundant, I just want to make sure I'm clear on everything:

In the tech articles, under the lists for ECM interchanges, there is a list of cars with the 165 and a list of ones with "1227730/16196344/16198262" Does this mean that any of those will do as a '730, or are there only certain cars in that list that have a '730 I could use?
If any will work, Regardless I do need a memcal from some sort of V8, correct?

Also, let me make sure I have this right..I need...
'730 ECM with plugs and about a foot of wire from them
V8 MEMCAL
MAP sensor from whatever the donor car is, along with the plug and some wire from it

 

1227730/16196344/16198262"=same ECM
yes you'll need a v8 memcal
Everything else is right accept that you don't need "the foot of wire".

 

Yea, those are just other part numbers for later versions of the 1227730 and they will work. You're right on with everything else. As far as the memcal, according to your info, you can probably use the part #16151348 which is the AUJP for an L98. Just follow the directions in the PROM burning tech article. You will change a few parameters in your start-up .bin which reflect the changes needed for your engine (injector constant, cylinder volume, etc.)and burn them to a new chip but you'll need the memcal for the limp home and knock filter stuff.

 

Sure he does, so they can sit in the back seat in a ziploc bag for the next 2 years.

Seriously, they will come in handy for repairs if he screws up one getting them out of the '165 plugs.

 

You are right, they are good to have. Just didn't want him to think it's NEEDED to complete the swap. I did the swap a few years ago on my car. Just converted my friends 89 IROC-Z to SD. Took about 3 hours, not too bad......

 

http://www.moates.net/product_info.p...products_id=37

While the 85 ECM has its limitations especially with data transfer rate, wouldn't this work? You'd have to desolder/resolder some pins in the ECM (Moates has insturctions for this) but it would allow you to run a flash chip in your 85.

 

flash chips was not an issue....

 

So, actually I could either get one from the yard (if they have an L98 somewhere) or from....a dealership, I'm guessing? How much does a dealership charge for that part?
By the way..sorry, but I'm still a bit foggy on comp acronyms...AUJP..?
Hopefully I'll be going out to get this stuff tomorrow afternoon.
And thanks for the effort, siggy, but I don't think I'll be going back on my decision to do this, now. Gotta dive into this new stuff sometime..

 

Try here for the memcal. AUJP is the broadcast code. It tells the specific application the memcal was used for. AUJP was used in some of the '730 f-bodies which had an L98.

 

Alright. The yard had no f-bodies, so I grabbed a '730 out of a 93 corsica, with a little bit of wire. I'm going to get the MAP and a connector for it in a while here, at the moment it seems like I can wait a while for it. I'm going to start on this soon, within the next couple days. If I can't find a memcal on ebay, I'll get that one from GMPD.

Oh, it might be a little early to be asking this, but what editors and burners, or whatever hardware do the majority of you guys prefer to use for burning? From my understanding some hardware is better than others. I just don't want to jump right into it and buy something I find out isn't what I want.

Thanks again

 

Eh, I've decided that since I don't have a chip anyway, I'm just gonig to go with a PROMinator. Before I can buy one, though, I need to know what the chip size is. Anyone know where I can find this?