EPROM Memcal Replacement Question
 

I have a question about replacing the factory EPROM in a '165' ecu memcal. I currently have two EEPROM 27SF512 chips. I also have the GP1 Package from Moates. Which allows me to quickly swap chips when I need to burn them. My tune is pretty well dialed in at this point. So I am looking for a more permanent solution since the chip can move a little sometimes and throw a code 51 memcal error. I am looking to solder the chip in to prevent this from happening. Is it possible to remove the factory UV EPROM chip and directly solder the 27SF512 EEPROM chip in its place? To clarify a little I dont mean putting a ZIF socket in place of the factory EPROM I mean soldering the new chip in place of the old. I cant find any posts on the forum directly stating if this is possible or if there is some issue doing it this way. I do know that the G1 adapter exists I would just rather solder the new chip in place of the old on the memcal if possible for easier removal.

What I have now
GP1 Package: http://www.moates.net/gp1-package-gm....html?cPath=64
HDR1 Memcal Header: http://www.moates.net/hdr1-memcal-he....html?cPath=64
165 MAF ECU

Re: EPROM Memcal Replacement Question
 

I use a d2 dip and solder it in , or use a pocket programmer and reprogram the 27c128
https://cimg9.ibsrv.net/gimg/www.thi...25373b6255.jpg

Re: EPROM Memcal Replacement Question
 

I looked around on moates website and found the d2 28pin DIP socket it was not as easy to find on their website as their other parts. Is this what you are using? It looks like its only $2. This would work for what I am trying to do. Basically rip out the old EPROM and solder the socket to the memcal and solder the legs to the d2 dip socket?

D2 28pin DIP Socket: http://www.moates.net/d2-28pin-dip-s....html?cPath=31

Re: EPROM Memcal Replacement Question
 

You got it, once the eeprom is socketed in the memcal you can use a hdr1 to flash directly without removing the eeprom (sst27sf512).

Re: EPROM Memcal Replacement Question
 

Thanks Tuned Performance that answers all my questions.

Re: EPROM Memcal Replacement Question
 

The gp1 zif comes off of the d2 that’s soldered on the pcb.

Re: EPROM Memcal Replacement Question
 

btw you don’t have to solder to the dip, the insertion is a tight fit unlike a zif.

Re: EPROM Memcal Replacement Question
 

Yah I figured I would work out the details when I get it in the mail. I have never used one before. So if I have any questions I will post here.

Re: EPROM Memcal Replacement Question
 

To answer your original question directly, yes you can solder the EEPROM directly to the MEMCAL, and then you would use an HDR1 to program the EEPROM. I've done this a few times.

Re: EPROM Memcal Replacement Question
 

Here is my experience soldering a 27SF512 EEPROM directly to the memcal after removing the old EPROM UV chip. Not using any zif sockets or adapters. My ECU does work after replacing the chip with this method. My soldering is not very good but you should get the concept. Remember to pay special attention to making sure your soldering does not bridge any of the legs.

1st: I cut the legs of the EPROM and removed the chip
2nd: I cut the legs of the chip flush with the plastic of the memcal. Do not pull on the original EPROM when you have cut most of the legs just be careful and cut the legs.
3rd: Bend the remaining portion of the legs down in the plastic of the memcal with a small screwdriver
4th: Make sure you position the chip in the right direction illustrated by tuned performance earlier in the thread.
5th: Be gentle and push in the new 27SF512 chip into the memcal and make sure all legs are seated properly.
6th: Get out a small soldering iron and solder in each leg. You need very little solder for each of the legs. If you use to much your going to have issues bridging two legs together.
7th: Put it in your ECU and test.

EPROM Removed, Legs Cut Flush, and Pushed Down in Memcal
https://cimg2.ibsrv.net/gimg/www.thi...847d8aae55.jpg

27SF512 EEPROM Pushed into Memcal Not Soldered
https://cimg4.ibsrv.net/gimg/www.thi...251d57770d.jpg

New 27SF512 EEPROM Soldered Into Memcal
https://cimg5.ibsrv.net/gimg/www.thi...7e250a7647.jpg

Re: EPROM Memcal Replacement Question
 

To remove the soldered in prom . Pry in the prom and press your soldering iron down on each leg. This breaks the solder joint. I have never left the legs ion the memcal they seem to come out with the prom.
you might have to repeat the prying up process a few times but it comes out complete.
I just prefer the zif Incase the eeprom fails. I have had a couple duds from moates.
It looks like your soldering iron maybe your wasn’t getting hot enough. I use mine at 550f.

Re: EPROM Memcal Replacement Question
 

I actually like these better than the Moates version:

https://www.ebay.com/itm/GM-MEM-CAL-...-/112553592450

GD

Re: EPROM Memcal Replacement Question
 

I’ll sell you one lol
https://www.thirdgen.org/forums/engi...k-adapter.html

Re: EPROM Memcal Replacement Question
 

If I needed one.... I have extra at this point since I went EBL with my personal car. But I did use one daily for a year or so without problems. The low profile ZIF seemed to work well and take up less space than the Moates version.

GD

Re: EPROM Memcal Replacement Question
 

My soldering iron is just a very cheap one but it has a fine tip. I have a better quality one but its much larger. As long as it works is all I am worried about at the moment. Honestly it was not as hard as I thought it would have been so overall I am happy.

Re: EPROM Memcal Replacement Question
 

i need some help with a prom for a 1992 pontiac trans am 5.0l

PROM DELCO AXXB 3063

any info would be helpfull

looking for new old stock if possible

but ideas anything would help

Re: EPROM Memcal Replacement Question
 

Re: EPROM Memcal Replacement Question
 

Is there anything you don't have in your collection? LOL.

GD

Re: EPROM Memcal Replacement Question
 

I sure have a lot of memcals that’s for sure lol

Re: EPROM Memcal Replacement Question
 

is it new or used or just old new in the box???
i was looking at it and its listed used?

Re: EPROM Memcal Replacement Question
 

It’s new

Re: EPROM Memcal Replacement Question
 

Not that it really matters since they aren't really a failure point. If you want ultimate reliability then have AXXB burned to a 27SF512 chip and stick it in an PROM adapter board. Then you have a NEW chip and it hasn't been sitting on a shelf for 25 years. You also have the opportunity to customize things like cooling fan temps (for lower temp thermostats, etc), VATS disable, and other changes.

Tuned Performance is a very reputable member and ebay seller - if he says it's good you can bet on it, and I'm quite positive he will stand behind it also.

GD