Page 1 of 1
M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 2:59 pm
by march109
Searched everywhere on the net for an answer and then remembered the good old zoners use M30s all the time!!
So I have a B plate 732i with a knackered head. The engine in the car is a M30B32 with L-jet the engine I have to go in is a M30B34 with motronic! This is just an engine that was lying around and is unfortunately without ancillaries. Or management.
The management I can sort from another donor however I am almost sure I will also need a whole host of other parts. But I don't know which.
So if I was to drop the M34 (or M35 if I'm going to all this trouble) into a previously L-Jet engined car what do I need?
And will I end up on some anti anxiety meds if I even try it??
Thanks in advance for any help!!!
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 3:06 pm
by Speedtouch
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 5:04 pm
by march109
Wicked looks like a ton of aggro then. Need to see if I can get a direct replacement first then I think.
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 5:10 pm
by Speedtouch
True, but there would be significant benefits to be gained from the larger engine and better management. It would probably be more economical too, giving a saving in the long run, assuming you plan on keeping the car for a long time...
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 5:32 pm
by march109
Actually the car is that nice that an original engine would probably help its value quite a bit. Though most couldn't tell the difference between the two engines once in situ.
I will have to have a think.
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 5:46 pm
by pianist
Maybe I don't get the question but if you got M30B34 which is motronic then all you need is the engine loom with ECU
Unless the plug that connects to the fuse box (might be wrong but i think its c101) is different then you would need to splice it up and rewire using your old plug
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 5:49 pm
by march109
The engine came a virtually a bare block and head!! And as such has just sat on a pallet in the corner of the workshop for the last 12months so there's quite a few bits missing.
Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Wed Jan 29, 2014 6:04 pm
by pianist
but as I gathered you do have donor car as in "The management I can sort from another donor..." ?
What bits are missing there isn't much on that engine as it is lol? maybe it would be cheaper to get another donor car that has all the stuff you need in it
I think "leeparks" here was seling his alpina b10 m30b35 setup for a good price if he still has it
P.S. just trying to help no need to shout at me

Re: M30B32 L-Jetronic to M30B35 Motronic
Posted: Sun Feb 02, 2014 9:32 pm
by Andyboy
The 732i was Motronic. All of them were from 1979, the first car to ever use it. These old E28/E23 M30's all have the same head casting, the 258. The cam is different because the L Jet ones have a small skewer gear fitted to the front of the cam to drive the distributor and the Motronic ones have an adaptor to take the rotor arm.
I wouldn't bother with the 3.2 engine anyway - you can buy an old 3.5 for a rebuild for buttons, nobody wants them.