77 E12 motor into a 77 630SI

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canada karl
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Joined: Tue Jan 06, 2009 3:50 pm

77 E12 motor into a 77 630SI

Post by canada karl » Tue Oct 01, 2019 9:43 am

Could the motor just be swapped in or would the electrical "brain" from the E12 have to be installed as well? Any other issues?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

canada karl
Posts: 663
Joined: Tue Jan 06, 2009 3:50 pm

Re: 77 E12 motor into a 77 630SI

Post by canada karl » Tue Oct 01, 2019 9:44 am

Should read CSI
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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Lock
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Re: 77 E12 motor into a 77 630SI

Post by Lock » Tue Oct 01, 2019 12:32 pm

From what I've read you can swap the engine directly just fine. Take a look at the labels on the ECUs, they should be identical as the years are the same. If they're different (either number, color, or both) you can swap them out, but because it's all analog it wouldn't make a noticeable difference just slight upgrades in the circuitry. I have used an L-Jet 633CSi computer in my 528i for testing and it was fine, the wiring is almost the same with the exception of the aux air valve, but that's just jumpered from the fuel pump + and not related to the ECU anyway.
1979 528i 5-speed conversion G260/6
1980 Honda CX-500

canada karl
Posts: 663
Joined: Tue Jan 06, 2009 3:50 pm

Re: 77 E12 motor into a 77 630SI

Post by canada karl » Tue Oct 01, 2019 7:27 pm

Thanks for the info :D
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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