mefi1, mefi3, mefi4 -Teach Me, Lesson
 

So what is the difference between these ECU's? What did they come on? What years were they used? Which is best to reprogram for 540CID and heads and cam? Which is best for supercharging?

Does anyone have a source for the mates for the efi harness-a connector end like on the ECU box?

Why can't we get a program so we can reprogram the computer?

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

I found this:
http://www.paceparts.com/index.asp?P...D&ProdID=84483

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

What do you think about changing out the mefi computer to a programmable ECU like Accel DFI or Holly? Which wuold you recommend? Could you take a stock 500EFI harness and put the correct plug on it to plug into the new ECu or could you make an adapter/jumper harness to conect the stock harness to the DFI or other computer?

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

Do you have a bad ECU I can take apart for the connectors?

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

What are the connectors used for the MEFI3 and 4 ECUs? Do they have a name? How many pin? Where can I buy them- the male and female connectors?
Are they Delphi micro-pack connector? 24 or 32 or 36 pin?

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

I found that they are 32 pins.

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

ttt

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

Do the MEFI systems have the ability to work within different load ranges at one RPM as do the aftermarket offerings. Meaning, does the ECU have the ability to set different fuel and timing requirements at different load points within one rpm range. (example: 3500 cruise (80-85 kPa/36 deg) and 3500 acceleration under full boost (~140-150 kPa/28 deg)). I feel these are keys to optimum fuel economy and performance.
Can you program timing assistance for in and out of gear idle control to be used in conjunction with the IAC?

I've programmed a few different ECUs (FAST, Holley Commander, etc...) but never have had the opportunity to play with a MEFI system.
Just curious..
Thanks,
Dave

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

Yes, the mefi software allows you to change the fuel and timing maps according to different loads at the same rpm. Yes, you can put the timing wherever you want it, again, based on different loads and rpm. It is for the most part infinately variable. It will do whatever you want it to do as long as you are smart enough to know.

Re: mefi1, mefi3, mefi4 -Teach Me, Lesson
 

800xcr,
Is that true for the MEFI 2 ECU as well or only the later models? Specifically "Can you program timing assistance for in and out of gear idle control to be used in conjunction with the IAC?"

Rick