Can anyone tell me what the control unit numbers are for the ign. control module and the engine control module. And Is there any reason an 8 valve engine would not work in place of a 16 valve engine. The only difference I see is the obvious one has 16 valves and one has 8 They basically the same block and sensors. Right??

"Can anyone tell me what the control unit numbers are for the ign. control module and the engine control module."

What year??

This is a 1989 740 non turbo

Okay...for a 1989 16-valve 740 N/A, the original Bosch part number for electronic control unit (fuel injection) is 0 280 000 562 -or- 0 280 000 571. I cannot find a part number for the ignition control unit, but I did note that the 8-valve 740 n/a uses a different ECU. My assumption is that swapping in an 8-valve motor would entail swapping the fuel injection system, harness, sensors and control units from the donor car as well.

Thank you. I did change the ecm with a 280 000 556 from a 1989 nt 740 and the engine wire harness. It runs a little better but only runs for a few mins then starts to sputter and dies. Rpm's seem a little low, but even so its hard to start and when started it will run for a few mins and sputter and quit then its starts with a little cranking more than it should be it will start run and do the same sputter and stop. unless I keep my foot on the gas about 2000 rpms, I have checked the fuel pressure its about 40psi and rests at about 50psi still hard to start. I changed the rsr and no difference, I changed the pick up sensor on the trans and no difference. As it quits the rpm's slow down along with the motor. I changed the fpr with several copper terminals and the aluminum type no difference. I changed the main fuel pump same thing and the in tank pump same thing. I even went as far as changing the icu and its wires no difference. No fuses get hot and I changed the amm nothing.I changed the knox sensor, and coolant sensor same thing, what next?? Frustered I need to sell this car but can't like it is. Help--you can call or email me its faster at 818-708-7052 and I can call you back or mail me at ufarley@earthlink.net Thank you Chuck