phanormthtrodex

I've been having trouble with my iroc idling high, RPM insanity, and most recently, the timing got off after replacing my distributor and its been absolutely impossible to set it correctly ever since.


So as I was peeling/scraping these crappy stickers off my air intake, my heart sinks. I realize one of them says ADS Superchip. Could this be why my car's been acting so crazy?! There are likely a lot of bad sensors/etc/ but if it doesn't even have the right brain, I'll never be able to get things to work properly!

Optimistically, I hoped the P.O., in the true ***** style, had just stuck the sticker on the car to increase performance. Sadly, not the case. Pulled the ECM, cracked the cover, and sure enough, a POS aftermarket chip is in there...

Some kind of microchip, and what looks like two resistor networks. And some of the worst cold solder joints I've seen. I realize that's why the thing had that black plastic cover glued on, to hide their shame in their terrible craftsmanship.

Just for kicks, I called a Chevrolet dealership to see if I could get a factory MEMCAL. They don't have them, and they recommended for me to buy a hypertech

Seriously guy?? I tell him I'm calling *because* there's some junk aftermarket in there, and I want this beast stock, none of this 'performance' BS. He then, again, recommends a hypertech, and I thank him and hang up, shaking my head.

I couldn't find anything online about this chip or what modifications it makes. Labeled as "ADS Superchip 8718-A" The actual chip itself is a UV-erasable PROM, I've even tracked down the datasheet - it's a M27128A-2F1

http://www.alldatasheet.com/datashee...7128A-2F1.html

This perked me up, as I realized I could potentially reprogram the chip. I've got a degree in electrical engineering and have done lots of work with microcontrollers, flashing chips, that sort of thing. So I should have a good background to learn this PROM stuff.





TL;DR:

Is there an easy way to basically emulate the stock MEMCAL for now using this or another chip? (Not sure how these resistor networks relate to what's on the true stock chip.)

From the datasheet, it looks like I could write some microcontroller code to turn it into a programmer for this chip. I have some reading to do. But first, I am extremely interested in pulling the data from this chip to find out what the heck it's actually doing.

Does anybody know anything about this chip and what it does?? I've noticed, when I get to WOT, my RPMs will suddenly jump and peg at max (on tach, and I can tell it's what the engine is actually doing.) I don't want some chip pulling this kind of crap on me!

And could I reuse it, or should I invest in one that's meant to be used as such?




A note:
I am absolutely not against aftermarket stuff, performance mods, /etc/. What I am against, is off-the-shelf bullcrap like this, ZOMG K&N ARE THE BEST!, and stuff being pushed by people who don't know what the f they're talking about (which are mostly the people who make such products) The videos on the K&N website are laughable. The "tests" they perform on their filters? Complete bull. My day job, I'm a test engineer, and I'd be fired if I wrote test cases like theirs, they don't even truly test their claims (specifically the one where they "debunk" the MAF-fouling due to the oily filters)

*end ramble*

RJMcEachern

i use Moates.net for all my chips in an 87 GTA 5.7L, I bought 10 chips for 45 bucks, a ZIF socket and just added to current mecal, take a pic of it and I can help ya if need be but an electrical engineer should be good to go :wink:

Get the chip(s), burn your bin for the stock calibration, and go from there. I did this to mine as it had a Hypertech chip and ran like **** until i replaced the chip with a stock bin and started modifying from there for what the engine wanted.

RJMcEachern

RJMcEachern

i use this with a ZIF socket on it...

https://www.moates.net/g1-memory-ada....html?cPath=64

I also use these chips...

https://www.moates.net/c2-sst-27sf51....html?cPath=26

I use TunerPro RT as the software for logging and tuning

RJMcEachern

phanormthtrodex

Awesome, I'm excited to get started on this. This circuit board does have a DIP socket, so the chip is removable, but I'm wondering what the purpose of these resistor networks are? Were they on the stock memcal? I can't find a pic of the stock one, and it looks like your socket has none.

Ill pull the ecm again tomorrow and post a pic of this. Thanks for your help!

I've played around w Tunerpro rt a bit, but wasn't able to get it to work. A serial port moniter showed that data was actually coming in, but not to tunerpro's satisfaction. I had breadboarded the circuit and was using an arduino as the serial-to-usb middleman, so that was complicating things. What do you use with tunerpro?

phanormthtrodex

Ok, found a pic of the stock memcal and a link that explains the resistor networks for limp mode and all. But you can only plug in either that adaptor or the stock memcal though?I don't get why it says the adapter requires the stock memcal for limp mode and spark retard, it seems like its either/or...

RJMcEachern

i guess an electrical engineer could probably do away with those, but the general public probably not. I think they went this route for mass consumption, i just use the adapter on the stock memcal with the ZIF socket, sticks out a little but the cover still fits (barely) and makes chip swaps a breeze.

I am going to be doing some tuning runs today so i'll snap a pic of my memcal, with chip, socket, etc. I use a USB cable that made specifically for the OBD1 GM diagnostics port, you can make your own, for me the 20 bucks was well worth it.

RJMcEachern

ULTM8Z

Yeah after all the fine tuning I've done in my chip to get it where I'm happy, there's no way sort off the shelf chip would ever come close to being "right " for my set up.

RJMcEachern

I followed Grumpy and Traxxion (among others advice), give the engine what it wants, timing, fuel, etc. I do only run 93 octane, I can get 110 octane aviation fuel but where I am at is autocross and under 40mph usually so I don't think this will give me any real world benefit.. oil changes every 5k miles with Mobile 1 Synthetic, she is good and fast

RJMcEachern

phanormthtrodex

Well I finally got my timing set right. Using a timing light, set it to 6* BTDC, and when I plugged the EST bypass back it, it was suddenly at something like 6-8* ATDC!? I'm guessing this chip is screwing with the spark advance?

Finally, just adjusted it to where I could hear no knocking, and left it at that. I've got a mechanic friend who was helping me and it was confusing him as well. (No shade tree, he works for a dealership)

In any case, I'm going to order a blank chip asap and burn the stock bin on it, so I actually know what I'm dealing with.

How much of a problem is it that I don't have the stock memcal? Because all I've got now is this stupid mystery superchip jacking up my tuning.

RBob

iTrader: (1)

The wires from the distributor pickup coil to the ICM are reversed. The chip can mess up the timing, but that is a 12* reduction, which could easily have the distributor firing on the next cylinder (rotor/cap phasing).

So if it does it with a stock BIN, reverse the pickup coil wires.

The only reason a stock MEMCAL is required is to set the cylinder select in the ECM hardware. That affects the injector firing rate.

RBob.

phanormthtrodex

AH I get it now. After finally looking up how that adapter is installed, I see how they keep the resistor networks in the circuit, and the original PROM is still there, but just hanging out, not connected at all.

Worried about the resistors though, as the stock memcal is long gone from my car...

From moates.net:
"The resistor packs.....are custom laser etched type resistor packs making them extremely difficult to duplicate. In other words, you need these resistor packs, you cannot copy them (as of right now anyway) and your car will have a hard time starting without them."

crap...here's hoping this ADS company has the right (or close) ones. Highly doubtful, as they couldn't even solder the dang things on the board properly...

phanormthtrodex

Well this kinda sucks...found mine on ebay..$175 though.....

http://www.ebay.com/itm/1987-305-TPI-Camaro-Firebird-Automatic-Computer-Chip-Memcal-PROM-ABUN-/360585769722?pt=Motors_Car_Truck_Parts_Accessories&hash=item53f49632fa&vxp=mtr
Seems like it'd be round about that much for blank chips, adapter, programmer, etc....

I'd much prefer to burn it myself, but then I'd still be stuck without the correct resistor chips. Errrg stupid P.O.....

maybe if I'm *incredibly* lucky, I can dig around the car and find they just tossed the stock memcal under the seat or somewhere......there's no way...and it'd likely be ruined anyhow....

RBob

iTrader: (1)

Relax, the resistor networks (CALPAK) only does two things: sets the cylinder select (easy to bypass), and sets up limp mode fueling, which isn't required.

Note that this is for the TPI MAF cars. The TPI SD cars also have a knock filter on the MEMCAL............

RBob.