Engine Conversion

[JohnE1998]

Hello everyone, new to the group!
So I recently bought an E38 shell after a long time searching. It is a 1998 model originally a 728i. I have sourced a donor car which is a 2000 735i that has had the body cut for another car. All the looms are intact. My question is how much of the loom is going to require changing? Not my first engine swap but my first bmw engine swap. Awaiting exact details on the donor car and will update when I have them. Any help greatly appreciated


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[Timm]

The engine loom and ECU are vastly different between the two models, so you will need those to start with

[007008]

I don't know about euro cars, but in general a 98 was a cable throttle and on facefilt they switched to throttle by wire. At least on v8 cars. Also in general the DME is the wiring link between engine and chassis. Your best chance of making things work (easily) is to use same year or era and stay away from the pre and post facelift mashup. Again I'm not up on 6 banger ins and outs.

[CPHES]

Get a 2.8 from 1998 - sell the 2000 735 parts to fund it.

You have 2 issues. 1998 is pre facelift. 2000 is subtly different in both engine components and wiring - and the v8 vs I6 wiring is different too.

[JohnE1998]

The engine loom and ECU are vastly different between the two models, so you will need those to start with

Thanks for the reply, have absolutely everything needed in the donor car including the worst case scenario full loom engine and interior

[JohnE1998]

I don't know about euro cars, but in general a 98 was a cable throttle and on facefilt they switched to throttle by wire. At least on v8 cars. Also in general the DME is the wiring link between engine and chassis. Your best chance of making things work (easily) is to use same year or era and stay away from the pre and post facelift mashup. Again I'm not up on 6 banger ins and outs.

The 728 that I have definitely has a cable throttle, if the DME is similar across both the donor and the 728 is it likely that everything will work together?

[JohnE1998]

Get a 2.8 from 1998 - sell the 2000 735 parts to fund it.

You have 2 issues. 1998 is pre facelift. 2000 is subtly different in both engine components and wiring - and the v8 vs I6 wiring is different too.

Are the shells the same in both facelift and preface lift? The trouble I have is that I am in Ireland and e38s are extremely scarce here and I am no stranger to working on cars (ex mechanic) so the workload Is not so much an issue for me I’d just like to gather some info on the swap before I take it on there is no point asking around people in the trade here as few of them have ever worked on one and even less have attempted an engine conversion

[CPHES]

Two choices - source a pre facelift 2.8 - from a 98 e39 - or swap the whole 2000 735 in. You will likely need as much of the loom as possible - a site like realoem.com will help you determine what is different. One thing that you will need is the keys / ews / dme from the 735, and swap all that. I don’t think it will work if you use the 735 dme ( engine brain ) with the old 728 key. That is where the details of this will make you nuts.