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Bmw Efi?
https://slantsix.org/forum/viewtopic.php?t=44028		 Page 1 of 1
Author:  TNT440_Cbody [ Sun Mar 13, 2011 9:53 pm ]
Post subject:  Bmw Efi?
Has anyone ever tried to convert a Slant Six using 80's BMW fuel injection from a 535? The engine size is almost the same, (3.5L) and the computer's wiring harness is actually relatively plug & play- at least from 80's BMW to 80's BMW...

I found an '89 535i for $400 (with a blown head gasket) that I am thinking of picking up. It'll have a low and high pressure fuel pump, 6 injectors that I know can be swapped out for higher flowing Mustang 5.0L injectors, and of course the benefit of having the entire fuel system from a parts car.

The BMW system has crank and flywheel sensors though. I'm not too worried about the crank sensors but what do folks do for flywheel sensors?

What are some advantages/disadvantages to going this route? Can I use all of the BMW stuff and then upgrade the computer to a MSII? I am not sure what parts are compatible with the MSII (I know, I know, I need to read the F-ing manual) :lol:

Sorry, kind of random thoughts but it seems to my naive mind like it could work! :D
Author:  olafla [ Sun Mar 13, 2011 10:47 pm ]
Post subject: 
Hi TNT440_Cbody, and welcome to the forum.

Going with the flow is not very progressive, so just keep following your ideas through!

I usually don't comment on injection stuff, as I am a carb man myself, but I think you should take into consideration the capability of a non original computer when it comes to handle different signal input from the air flow/mass metering methods. I am definitely on unsure ground here, but I seem to recall that the germans used various measuring methods and formulas to calculate the amount of air entering the intake, up through the '80's.

BTW, the blown head gasket is a known issue with the 3.5 litre.

Olaf.
Author:  Dart270 [ Mon Mar 14, 2011 6:01 am ]
Post subject: 
You can certainly use MSII to drive that (or about any) injection system, but it'll take some DIY wiring skills.

Flywheel and crank sensor should be the same thing. Maybe you mean cam and crank sensors??

I don't know much about BMW EFI/wiring/architechture, so I can't offer much more...

Lou
Author:  Matt Cramer [ Mon Mar 14, 2011 9:10 am ]
Post subject: 
The setup with a sensor that reads the flywheel teeth is going to be nearly impossible to swap over unless you have the same number of teeth on the flywheel.

The one with a crank pulley trigger just uses the sensor on the end of the crank and an inductive pick-up on the #1 cylinder spark plug wire.

We've actually got a kit that is based off the MS2 processor and plugs into the 535 wiring harness.
Author:  WagonsRcool [ Mon Apr 04, 2011 3:59 pm ]
Post subject: 
I would generally avoid BMW for cost reasons; on average replacement parts tend be more expensive / more difficult to get than for US or asian makes.

I also noticed that German car makers don't tend to provide repair INFORMATION, as much as they give procedures. "Plug in special tester xyz, follow the on screen instructions. If part A fails test - replace." They don't specifically tell you HOW a system or part is supposed to work - which makes diagnosis or modification difficult.

Lastly, as a mechanic one of the more common faults with old german (european) cars that I've found is general deterioration of the wiring harness. I would look at your eng harness carefully, & if insulation is cracking or terminals are oxidized they I'd walk away.
Author:  DusterIdiot [ Mon Apr 04, 2011 8:55 pm ]
Post subject:  Meanwhile...back at the time machine...
A decade back...one of our former members in Seattle had taken the time to look at an intake for a BMW and had started some work toward sawing a couple intakes up to use on our engine it was an early 80's or late 70's Bimmer...I think the original project is now lost to the ether...

-D.Idiot
Author:  Matt Cramer [ Tue Apr 05, 2011 8:15 am ]
Post subject:  Re: Meanwhile...back at the time machine...
Quote:
A decade back...one of our former members in Seattle had taken the time to look at an intake for a BMW and had started some work toward sawing a couple intakes up to use on our engine it was an early 80's or late 70's Bimmer...I think the original project is now lost to the ether...

-D.Idiot
I still have the upper plenum off an early '80s 528 that I was thinking of fabbing up runners to mate it to a slant six head. Never went anywhere with that, but I may dust it off some time after I get the current round of mods working.
Author:  Reed [ Wed Apr 06, 2011 12:09 pm ]
Post subject:  Re: Meanwhile...back at the time machine...
Quote:
A decade back...one of our former members in Seattle had taken the time to look at an intake for a BMW and had started some work toward sawing a couple intakes up to use on our engine it was an early 80's or late 70's Bimmer...I think the original project is now lost to the ether...

-D.Idiot
Yup. That was Brett Kempton. He moved from the Seattle area to some property he bought (I think on the Kitsap Peninsula) and disappeared from the slant six radar. I sold him a 66 Barracuda and my old 72 Satellite. :cry: Wish I had both those cars now (sort of).
Author:  Exner Geek [ Wed Apr 06, 2011 6:52 pm ]
Post subject: 
If you go ahead with this, how about pulling the head and comparing it to a Slant 6 gasket? I have never been able to do this with a BMW 3.5 head. And I don't want to hear about the Supra conversion kit that Sandy has.
Author:  Rob Simmons [ Thu Apr 07, 2011 6:31 am ]
Post subject: 
Hey Seymour,

Even though it got way off track and was very tongue in cheek when I did it...

I actually DID have Doug send me a used head gasket when I was stationed in Germany and I DID compare it to just about every BMW (and every other car I could find). The bore spacing and bolt hole arrangements weren't close enough to be considered feasible IMHO.
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