engine swap

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so what is the simplist bolt in upgrade motor
there are tons of comments but i want to use
the 85 5 series 5 speed thats already in
and the dual webbers
or is it better to go injected.
but i want simple thansk
 
Many Choices

Many people try and get an M30 engine with Motronic injection and 5-speed pair out of a late ('88 or '89) E24 or E28, as I believe this motor has 208 HP (the earlier mid-80s M30 has, I believe, 182 HP), and transplant the motor, 5-speed, Motrotrics (intake manifold, fuel rail and injectors, brain, and wiring harness) at the same time. I believe that the crankshaft position reference sensor is on the transmission bell housing, so the motor, the injection, and the transmission hang together as a set.

If you have a trani from an '85 5 Series, it may have the reference sensor already on the bell housing, or may have the the hole where it was removed.

Some folks don't like the look of the intake manifold that comes with the Motronics, and do the above but substitute the curved intake runners off an L-Jetronic motor from a pre-Motronic car like an E12 528i or an early 633CSi. I believe the fuel rail has to be modified to fit this manifold. I've never done it, but there are many posts on it. If I had money and needed to do another car from scratch, this is probably what I would do.

I have a mid year M30 (182 HP) engine with L-Jetronic injection from an E12 533i and a 5-speed from the same car. This is a simpler system than Motronics, but it has a conventional distributor requiring conventional setting of ignition timing. L-Jetronic doesn't use a crankshaft position reference sensor, instead getting position from the distributor. As such, it doesn't need a trani with the position sensor on the bell housing. As such, the injection system and trani hang together.

I could be wrong about any of the details in the above (except those pertaining to my own car).

There's nothing wrong with Webers if you like them and want to keep using them. Some folks feel that carburetors give better (more immediate) throttle response as compared with vintage fuel injection systems like L-Jetronic and early Motronic. It's hard to deny, though, that even vintage fuel injection is likely to give a better combination of easy starting, driveability, power, and fuel economy than carbs. I haven't touched my L-Jet installation in 15 years, and I can twist the key in the car for the first time in six months and it'll start right up, idle well, and pull away without stumbling.
 
setup

so is there a writeup on the details to put the e34 in
like the clearance issues on the pan the motor mounts and the
brake booster issue thanks
 
1st i presume you meant b34. word of advice, if you have a choice, you might want to go with a b35 - unless the b34 is either a euro engine or it has been more stoutly built to shed the anemic power (due to low compression ratio) of the b34.

are you going to run it with dual carbs, triple webbers or fuel injection? i think that answer will determine whether or not you will have to change the booster. if you are running injection, it might make a difference which manifold you intend to use - not sure if the log intake interferes. i am using the curved L jet manifold - no issues ... but then again, i have a 2800cs booster which is smaller than the 3.0cs booster.

i thought i had an article on the exchange, but i can't seem to find it. you might try a thorough search of the archives
 
engine fit

i think it would be best to go with the injection
so the B34 isnt all that its meant to be - meaning
as per the previous comments
i was thinking i want a bolt in]
but if the power is signicantly lower
then i need to know how much craziness is needed to
go another way
 
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you might be getting confused with the e34 and the b34....
One is a model of car and one is an engine. Lots of variations on both.
 
you might be getting confused with the e34 and the b34....
One is a model of car and one is an engine. Lots of variations on both.

Not to mention that the E34 ran the B35, which is the one to get. Lots of codes floating around.
 
engine fit

so is there some pics for the booster and pan fitting with the bigger engines
or just general comments on the different options
i want to make a desision what way to go
thansk
 
I used an 88 635CSi motor and it had correct oil pan and motor mounting points. If you use the e12 C intake runners and plenum the big booster is not a problem.
 
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