just bought a new project 1991 s10 with a later model 4.3l and 4l60e already swapped in. It has a 7427 with a chip from gmeprom.com. I can read the chip but when I copy it to one of my 27sf512 chips and put it in the computer the engine runs extremely rough and the check engine light comes on. I have tuned my other car with a 7427 and had no problems don't know what Im missing or doing wrong. Any help is greatly appreciated.
If your binary file is 32k and the'7427 uses a 64k rom then that's your problem. Either the chip you have is only mapping half of the rom to the ecu and using the OE rom for the other half or you are only reading half of it.
Ok finally had some time to play with my truck and it looks like I can only read half of the chip from gmeprom downloaded the bdyt bin from gearheadefi burned it to a chip and in my opinion the truck runs better now to get dataloging thanks for your help