Want to do an M30 swap

[gstuning]

In my experience the sensor is not really needed,

[Garageaholic]

all the impulse sensor does is fire the pistons in batches of 3, instead of all 6 at once.... everytime. It just wastes energy, that's all it's supposed to do.

[gstuning]

I don´t think that is correct,
The timing comes entirely from the timing wheel in the front,
both engine speed and piston locations,

Can you post where you found this information?

[Funkmasta]

all the impulse sensor does is fire the pistons in batches of 3, instead of all 6 at once.... everytime. It just wastes energy, that's all it's supposed to do.

<--This is for motors with electronic ignition.

The M20 and M30 have distributors, so only one plug will fire at a time...

[JoeMadoo]

I'm finally ready to do the M30 swap in my 325es. I have a sexy 735i w/ a 5 speed waiting for me, and a 325i wiring harness on its way. Does anyone in america have mounts for this, or do i have to wait like 3 weeks for the e30.de ones. I have fab friends, would it be relatively easy to make? Ill post pics of my progess. Is there any weird shit that you've guys have come across that I should watch out for while doing this swap like with the wiring harness or anything?

[euroshark]

Just get pinouts... If you have to reqire anything for the harness to fit the fuse box connection, it will be super easy with the pinouts. Make yourself a cheat sheet with the colors and their functions so its easy to cut and connect them. You might have to make radiator mounts if you dont use an E28 radiator. I used an early E24 radiator and there were no provisions for mounting it. Shifter linkage - don't cut anything. Everyone who says you have to cut the shit is wrong. You may just have to find the plate / mount and selector rod to fit. The 260/6 that the E32 should have will PROBABLY work with the stock linkage! Um... other than that... yes, buy the E30.de mounts, they are a perfect fit! I wanted to build my own, but I am SO glad I just bought some. Positioning the motor and building mounts would have been a huge pain in the ass. The exhaust downpipe from the E32 might work, but it might also hit the firewall, so be prepared to either do some chassis modifications (big fucking hammer) or build an exhaust system. Have fun!!

Are you going in from the top or the bottom? I went in from the bottom... Just removed the subframe, stuck it under the motor while it was hanging on the hoist, bolted the mounts up, and scooted it under the car. Then you just use the hoist to pull it straight up into place!

[JoeMadoo]

OK thanks alot, that really helps. I'll dive into in monday when I get my harness and see what happenes.

[bmw335isturbo]

I'm looking to do an M30 swap into my little 325es. I've done just about everything i could to improve upon the engine but i think its time to go bigger, and higher revving. I have a couple of questions for the pro's that have one this before.

There are a few different types of M30s from different models, which one would be easiest to install, electronically and physically.
It would make sence to me to just take the entire computer/wiring harness out of the doner m30 car and transplant it into mine. Would that match up to the existing stuff i have in the interior? or should i take a 325i wiring harness and use a 535i computer (both being 1.3 i believe?).
Is there any power difference between the e28 models and the e34 models with the 3.5L, or elecrical difference?
What should i do to the motor while its out? Cam, rebuild, etc. I'd like this beast to be smog legal also.
How bout a turbo'd M30 from a 745i???
Wonder what a flowmaster would sound like :)

Thanks to anyone who can give me some advice!

How bout a turbo'd M30 from a 745i???
---------------------------------------
Just my opinon if you are going to turbo the m30 do not take any short cuts bie a complete kit and start their.

[Rocla]

all the impulse sensor does is fire the pistons in batches of 3, instead of all 6 at once.... everytime. It just wastes energy, that's all it's supposed to do.

No. Or yes, Its the injection, meaning that injectors are fired as batches of 2 or all simutaniously if impulse sensor singal can't be read.

I don´t think that is correct,
The timing comes entirely from the timing wheel in the front,
both engine speed and piston locations,

Can you post where you found this information?

_MY_ information comes from DIS.

<--This is for motors with electronic ignition.

The M20 and M30 have distributors, so only one plug will fire at a time...

Yes, for clarity motronic engines have "computerized" ignition, controlled by DME itself, they have only cap and rotor, while older m20 and m30(l-jetronic) engines have real distributor with mechanical spark advance mechanism, meaning that advance curve is generated by distributor itself.

[JoeMadoo]

I already have a variable geometry turbo from an '07 porsche waiting to go in and a friend just waited to fabricate stuff.

So is that special little spark plug wire really needed or no?

[Rocla]

I already have a variable geometry turbo from an '07 porsche waiting to go in and a friend just waited to fabricate stuff.

So is that special little spark plug wire really needed or no?

No it's not needed, your car will run fine without it.

There will be slight difference on mileage and possibly a very small drop on performance, but since you are charging yours, it should not be mandatory.

[Garageaholic]

It's just there for efficiency, but makes the price of your spark plug wires almost double! just for the impulse wire!

[JoeMadoo]

So whats so special about the e28 535i radiator? How hard is it to make the E32 rad that I have work? Also if i got a radiator for an automatic tranny could i use those tanny oil coolers in the radiator to cool the oil in the engine?

[Axxe]

M30 swaps are the new purple!!

[oldskool3]

So whats so special about the e28 535i radiator? How hard is it to make the E32 rad that I have work?

I am pretty sure the rad will work as long as you can get clearance for it. You will have to build custom mounts for it though as it will not sit on the stock e30 mounts.

Thats why the e28 535 rad is used because it lines up with the stock e30 rad mounts.