Ok... I hope someone can answer this question for me. If you can it will be greatly appreciated. In 1986 GM produced 50 IROC Camaros with 350 TPI engines. What I need is the 4 LETTER code (not numbers) from the top of the stock computer chip ... OR the Scan Id # of the stock chip. If anyone could get me this information it would be greatly greatly greatly appreciated.

 

I believe the preferred MAF bin is ARAP.

 

**unhelpful text I earlier posted deleted, sorry for the garbage but no way I'm spending effort helping 86tpiTransAm after this:

https://www.thirdgen.org/techbb2/sho...threadid=73988

 

 

That's like the pot calling the kettle black there guy

 

I hgihly doubt that Memcal is readily available and I suspect they probably used just a Vette Memcal of some sort. However, that is probably your worst solution. The later MAF Bins are much better and the 1989 ARAP MAF Bin is probably the "best of the best" as your starting point.

I would suggest the 1986 Bins are probably the "worst of the worst" due to being the oldest. GM made a few revisions to the Memcals for the 1227165 ECM used in 1986-1989 with the better versions being the best.

Do a search on ARAP and you will find a lot of information on it. Just be aware that there is no "plug n play" solution. You WILL need to modify the eprom to get the best performance. If you are looking for a "plug n play" solution, then I recommend doing nothing - because that is what you are most likely to get.

 

I can't use the '89 due to having the cold start injector so the '87 is the latest chip I can use until I start burning my own. Right now I AM looking for a "plug n play" solution and the reason is that I'm running a 355 with 24# injectors and using the 305 chip. I'm running 36psi fuel pressure and STILL running rich. With a 350 chip I can get closer to the proper fuel/air ratio because the 350s used 21# injectors. Less Rich=Better MPG.

I will eventually start burning my own chips.

 

Have you done a search on the ARAP? According to people that are running the 89 in older 165s they don't even have to remove the CS. I think you should do more research because many pre 1989 165s MAF users are using the ARAP with no problems.

As for gas mileage, invoke Highway Mode and get even better gas mileage. Depending how much you drive, that alone can pay for your eprom burning equipment in a very short period of time. It (better gas mileage) paid for mine in just over a year.

 

Wish I had the time and patience to learn right now.

 

I had the same problem when I installed the 355, finding the right MEMCAL was a tough process but it eventually got solved and ran OK without custom chip burning.

That said, I picked up a lot of power and overall better performance/mileage when I started software tuning.

 

My GTA is an 87. I have a 165 MAF system. I use a modified ARAP bin. I can tell you that all you need to do is remove the connector from the CS Injector and you are in business. The injector itself does not need to be removed.

 

Thanks Matt.

 

No prob .

The CS injector circuit is completely autonomous of the ECM and operates using a switch that is threaded into the coolant passage of the intake manifold. Thus, if it is left connected and an ARAP based bin is used, the car will tend to get too much fuel on cold starts as the 89 - 90 MAF bins (one of which is the ARAP bin) use a cold start routine to increase the fuel supplied to the engine through the regular fuel injectors.

I also can vouch for the Highway Mode mileage gains..... While I haven't saved enough money to pay for my PROM burning equipment - YET, I do get substantially better mileage than I could ever have dreamed of getting with this kind of setup before I learned of the benefits of custom PROM tuning (thanks Glenn!! ).

 

you know the wierd thing I am running the 89 1LE bin slightly modified and I was having huge problem starting my car in the morning with CSI unplugged

same with the ARAP bin so I read somewhere that some one had pluged it in and low and behold my car starts after about 4 or 5 revolution with ice on the windows. and if I have to move my car before it gets a good warm up it doesnt bog any more.


any how those are my 2 cents you wont hurt any thing if you leave the CSI hooked up it may just start rich for you.

 

You might want to do a search on the 'extended crank time' symptoms people were seeing with the ARAP bin. That 1LE bin might have the same settings in that table that controls how many revolutions the ECM waits to see before it fires the injectors. I personally like the way mine starts with the stock ARAP settings in that table but I ended up tweaking them a bit for my friends 89 305 M5 IROC with an ARAP based bin.

 

I have meesed with the crank times it wasnt that it would crank a half dozen times then almost kick then I would have to turn the key again usualy the second time it started (barely) but now it starts right away with the CSI on