Firstfives.org

Hello,

At the moment the car has 518 67kw carburetor.
I've been thinking about motor swap for a year now but because I am a newbie I have no idea what motor to choose.

The motors I've been thinking about are
M52B25, M52B28, M54B25, M54B30.

Are these swaps even possible?
What kind of parts have to be changed with motor swap ? (rear axle ? etc.. )
Any better motor suggestions ?

Any help and ideas are appreciated!

Thank you.

They're possible, with enough time, skills and money, but not easy. All of them, but especially the 2.8 and 3.0 engines would be a huge increase in power. None of them will bolt up to the transmission and while strong enough, the differential would need to be changed, the ratio would be all wrong.

You might consider a M44 engine, still a 4 cylinder, but 4 valve and a 104KW rating for a nice boost. It would still need a different transmission, but would fit better and the existing diff would be more workable. It would still be a lot of work, but not nearly as much work.

I've been thinking about buying a whole new donor for motor swap. '
Like e36 or something where i can get all the necessary parts for it .
Money is not the problem because im not in a hurry and if necessary i will save up for it for a long time. In my mind I just want to do it one time and make it perfect. And big six is already like a obsession of mine

Also i have lots of help from friends and if necessary i will hire a mechanic to do it if it gets too hard.

Plandhta wrote:I've been thinking about buying a whole new donor for motor swap. '
Like e36 or something where i can get all the necessary parts for it .
Money is not the problem because im not in a hurry and if necessary i will save up for it for a long time. In my mind I just want to do it one time and make it perfect. And big six is already like a obsession of mine

Also i have lots of help from friends and if necessary i will hire a mechanic to do it if it gets too hard.

For simplicity sake you should look for an e28, and swap the subframes and diff and driveline all at once.. much easier than making parts or mixing parts from m5xs and m20s to fit a "baby six" into a car that SHOULD have a "big six" m30

From what ive read oh here other members have done e28 front and rear subframe swaps and suspension, and it sounds like a pretty straight forward bolt in process.

The rear subframe from an e28 does bolt in, the anti-roll bar is positioned differently and needs mounts welded, and you need the entire e28 handbrake cable. Also you lose the twin-piston rears for the e28's single-piston. But you get a more common diff with cheaper LSD options but you'll need an early diff cover to use the existing diff mount. The e28 rear has better suspension geometry, less squatting and snap oversteer. I'm doing this swap myself soon.

The front subframe isn't a straight swap as it's a fairly different, and according to some it's a worse design, but it can be done.

If I were you I'd get an e28 or an e34 (or both) and swap in the good parts, so either an M30B34 (drop in), or a M30B35 (more work but the best motor). If you want more power, get a turbo M106 or M102 from a Euro 745i. You can wind up the boost later.

e34 m50b25 ?