L-jetronic conversion

CoachKel

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A customer recently came in and asked if I could direct him on how to convert his 3.0cs to an L-jetronic efi system from an e12. I do not have those notes. The gentleman wants to attempt the conversion himself. I recommended he do a 3.5 later efi upgrade, but he already has a complete set of parts. Can anyone share wiring notes or direct me to a previous thread on this board? His ecu is a 0280 001 114 Thank you.
 
http://www.firstfives.org is a good start.



Table 1. Major Parts List (Robert Bondi)
Part Description Part Number Optional Comments
fuel injectors Bosch 0-280-150-152 X I reused almost new 77 530i injectors, but probably not as fuel efficient
fuel rail BMW 11-53-1-267-326 X Not needed, but superior to 530i in simplicity; stay with 530i fuel rail contraption if you like fuel leaks (unbiased opinion)
fuel pressure regulator BMW 11-53-1-263-782 X goes with fuel rail
fuel press regulator bracket BMW 11-53-1-263-848 X goes with fuel rail
FI wiring harness BMW 13-65-1-272-143 comes through passenger side fire wall; grommets of used harness will need help, but can't be purchased new without getting new harness
AFM Bosch 0-280-203-011 X Bosch (-004) from later 530i seems to work well also
ECU Bosch 0-280-001-122 Bosch (-118) of 1979 528i sounds interchangeable; make sure to plug in extra single wire from harness for tachometer signal in glove box area. I got a rebuilt. 1979 systems rumored to used both advance and retard.
combination relay BMW 13-62-1-272-131 12 terminals instead of 11 on the 530i
throttle body assy BMW 13-54-1-273-070 You can remove throttle switch plate of later 530i and install 528i plate if you drill a hole in throttle shaft and tap it with M4-0.70. Use advance port up top for vac hose hook-up from thermovalve on thermostat housing.
Coolant chamber may need attention.
engine wiring harness BMW 61-11-1-269-343 plugs into fuse box
ignition ctrl module Bosch 0-227-100-025 mount on unibody wall near windshield washer bottle
distributor assy with advance BMW 12-11-1-271-697
BMW 12-11-1-466-324 I got a rebuilt. Be careful with multiple part numbers; I didn't use these in my acquisition.
thermostat housing BMW 11-53-1-710-959 Needed for 80/81 system with at least 4 threaded bosses; make sure it works with your thermostat if you get a new one! Part # used by most M30 engines. Even 79 should require two bosses because of added thermovalve. Drilling & tapping your own only recommended if you have a blind boss present.
bimetallic aux air valve BMW 13-63-1-272-103 X Needed for 80/81 system; has adjustment screw
valve cover BMW 11-12-1-276-593 X Needed for 80/81 system; has raised boss with 2 M6-1.00 holes for new aux air valve. Part # used by most M30s, so make sure you get the raised boss.
AC compensation valve BMW 13-64-1-276-163 X 1977 doesn't have it, but 1978 and later seem to
intake manifold BMW 11-61-1-270-192 X you can use later 530i log manifold, if you plug some extra EGR holes and vac ports
throttle microswitch BMW 13-63-1-268-444 X only optional because it is part of throttle body assy; I bought new
throttle microswitch BMW 13-63-1-268-445 X only optional because it is part of throttle body assy; I bought new
45 C thermovalve BMW 11-74-1-264-132 connects vac advance from distributor to throttle body
3-port aux air valve vac hose BMW 11-61-1-271-604 X Needed for 80/81 system; seems to be NLA. You may find one new, but they are probably no longer manufactured by BMW. I made my own. Connects throttle body to both AC valve and aux air valve.
aux air valve vac hose BMW 11-61-1-271-602 X Needed for 80/81 system; goes over manifold
AC valve vac hose elbow BMW 11-61-1-271-571 X 1977 doesn't have it, but 1978 and later seem to
ignition coil BMW 12-13-1-363-629 make sure it is for pointless ignition
ballast power resistors BMW 12-14-1-360-676 mount on unibody wall near windshield washer bottle with heat sink paste
single wire O2 sensor BMP 4456 consider heated multi-wire model, especially with 530i exhaust headers
AC compensation valve bracket BMW 11-61-1-271-598 X 1977 doesn't have it, but 1978 and later seem to; this is 80/81 number, there is a different number for 78/79, but is probably similar enough to modify?
spark plugs Bosch WR9DS Lots of choices here, but this silver plug is widely recommended
various exhaust parts ? X several choices; you will be getting more parts or modifying…see link
vibration damper for AC compensation valve BMW 64-21-8-042-132 X 1977 doesn't have it, but 1978 and later seem to
FI harness 2-pole connectors BMW 12-52-1-706-121 X expect to see some cracked on a used harness
FI harness rubber boots BMW 61-13-1-358-330 X expect to see some cracked/torn on a used harness
coolant return pipe BMW 11-53-1-271-573 X Part of the 80/81 system; you can circumvent and use the earlier pipe, but the condition of mine encouraged replacement
coolant hose BMW 11-53-1-271-572 X goes with return pipe; connects throttle body to pipe
 
I have the tech article from the old cs register website titled:

"3.0CS DUAL CARB TO L-JET CONVERSION
by Jim Ockner
March 15, 2002"

I made a copy (file) 4 years ago in anticipation of doing the conversion on my coupe.
It proved to be invaluable. Very straight forward and detailed.

For some reason it was never transferred over to this site with the other tech articles from the old cs register site.

I'm happy to email the file to you. PM me with your email.

Thanks,

John M
 
You should let your client know that the 114 ecu is for the 3.5 liter euro motor.
 
I called Robert at Livermore Fuel Injection. He said he didn't imagine a problem to run the 114 as the compression difference between the two motors is not enough to screw things up. He said if one was 12:1 and the other was 8, then that would be a problem. I will pass the info along to my friend. I am too old to wrench now.

You should let your client know that the 114 ecu is for the 3.5 liter euro motor.
 
The Jetronic ECU has nothing to do with timing, just fuel.
Euro ECU's of that period dont have 02 sensors to moderate A/F ratios.
The fuel map will be for a 3.5 liter engine.
 
That's correct, as Robert himself stated, the fuel map of a Euro 10:1 motor will not be significantly different to adversely affect a 9:1 motor. He did not think it would make an appreciable difference. These are Robert's words. And yes, we did talk about the timing being independent of the ECU :)

The Jetronic ECU has nothing to do with timing, just fuel.
Euro ECU's of that period dont have 02 sensors to moderate A/F ratios.
The fuel map will be for a 3.5 liter engine.
 
The young lad now wants to convert to the later 1.3 system. I can't really wrench anymore to help him as my hands shake too much. I've seen bits and pieces of write ups for the motronic 1.3 conversion, is there a link that covers the wiring required on this forum? Thanks, Kel

That's correct, as Robert himself stated, the fuel map of a Euro 10:1 motor will not be significantly different to adversely affect a 9:1 motor. He did not think it would make an appreciable difference. These are Robert's words. And yes, we did talk about the timing being independent of the ECU :)
 
Calling Arde?

Someone will probably have thoughts on my (phone assisted) mis-type of supplications instead of applications! Seemed too funny to edit out...
 
More info here....


Motronic 1.3 conversion kit™ for your 535 - MyE28.com
www.mye28.com › For Sale / Wanted - Parts
May 10, 2009 - 25 posts - ‎15 authors
The Motronic 1.3 conversion kit™ comes with everything you see here! 1 M30B35 harness (or super eta harness on request) 2 M30B35 ...
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