Spare Digiplex MED 801A

What model/year were these installed? I have a pair from a QV collecting dust....

 

I wouldn't mind having a spare myself. I have the 80' GTBi. Not sure if they are all interchangable? Joe

 

I have replaced both of my ECU's in my 1981 308 GTSi. I removed the old 801A units and replaced them with "NEW", thats right New 802A units. The only difference is in the exhaust timing.

These units are running very well now for over a year and and half with no problems at all noticed. I even passed California Smog this year!!!!!!!

The 802A were for the Euro Spec cars and the 801's for USA cars becauses of tighter SMOG standards.

The only difference I can find in a Euro car is the Exhaust timing has a longer duration and the Digiplex timing comes from the intake side not the exhaust. As far as what fires the coils, it is the mag pick-ups on the Cam. The only way that could change is to physically move the pick-up position. The coils and the ECU’s receive 12VDC power through the L/H fuse box, fuse A and B. One side goes to the coils and the other to the Digiplex on pin #8 then bridged to the other Digiplex. The MAG pick-ups are what tell the digiplex to fire the coils. Inside the Digiplex there appears to be a solenoid tied to the vacuum. This, along with RPM, is what sets the advance. All other components appear to be the same.

Everything I see so far points to the 801A’s being retarded MORE to meet US Smog standards. Nothing more or less. I have heard of re-setting a US exhaust cam to the Euro spec to achieve the same performance. Not sure how to do that and I do not plan too, but all I n say for sure is that the 802A’s appear to make the car run better and smoother.

You might still be able to get the new 802A's from Eugenios Ferrari Service in California, Tell him you talked to Jeff in California City

http://emelbon.tripod.com/eugeniosferrariservice.html

Hope this helps

Jeff

 

Jeff, Are you saying you switched to the 802A without ANY modifications? Plug and play so to speak? Im guessing to make this switch BOTH units would have to be changed to the 802A's at the same time? Joe

 

I believe you have to change both units to the 802A. I dont think you can mix and match. The 801 is USA spec and is approx 5 deg more retarded, firing the fuel a little sooner for SMOG req.

I have been running these 802's now for 7,000 miles back and forth to Laughlin, NV about 280 miles from where I live, I have not noticed anything different about how it runs. Its staying cool, good pick-up power. I have not really noticed any difference. The reason I switched was my #1 bank ECU (801) was causing a popping kind of backfire when I would let off the gas. I traced it to the ecu advance unit was failing. I could not find anyone who could re-work them in the US or anywhrere else.

I found a diagram of the 802, and could not find any difference from the 801. So, I found the OLD New Stock of 802's and said, WHAT THE HELL, and I tried them.

Yes, it was plug and play. No mods required and the car started right up on the first try. Its been running great ever since. As I said before, I was worried about passing a CA smog check but my numbers were fantastic and the car passed with no troubles at all.

The advance is controlled by Vacuume from the manifold to a solonoid inside the ECU. I was worried that at Wide Open Throttle, the advance might produce pinging. Since then I have used a timing light to check this and the car is dead on with its timing at every speed even WOT. So I have to conclude that these units are identical to the 801's. I do not believe you can use the 803's 0r the 805 units. The 803's were used in the Quatrovalve and the 805 is for the 328 I think, not sure. But the 801/802 were used in the 1980-1982 308 2 valve cars only GTSi cars.

Hope this helps

Jeff

 

Jeff, I think my 84 QV has the 805A and it runs just fine.

 

The 801As and 802As are for the 80-82 FI, 2-Valve cars. The 805As that I have are for the 83-85 QV 4-Valve cars.......I may have confused a few posters earlier, my apologies.