Bmw M20 engine

[kiwi6539 3]

Just want to know how they compare to m30?

Fuel

reliability

Things that go wrong?

Are they too under powered for 5 series. On NZ roads?

Edited September 3, 2008 by kiwi6539

[bravo 34]

Not quite as good as m30 partly because they have timing belt, not chain, but still tough as nails.

Heads warp/crack if overheated, valves hit pistons if the cambelt breaks, valve stem seals go after a while, headgasket is common cause of overheating and head problems, minor vacuum leaks accur in the rubber parts of the intake system, airflow meter vanes can stick, cold idle valves (where fitted) can stick, tappets almost always are noisy, can be adjusted but often noise is dur to wear, not incorrect adjustment and you just have to live with it or replace cam followers, and/or camshaft.

Long list, but well maintained these motors do very very high kms and take a lot of punishment.

We ran an m20b23 in a dusty environment on the limiter in a paddock car for hours on end with no problems.

[kiwi6539 3]

Hey Bravo cheers for advice.

Looking at getting M20 b25 525i just wanted to know whether to hang out of later m50 but I want manual and there arn't to many about.

So as long as looked after they are strong engines

[hybrid 1040]

Some would say bullet proof

[OLLIE 26]

Hey Bravo cheers for advice.

Looking at getting M20 b25 525i just wanted to know whether to hang out of later m50 but I want manual and there aren't to many about.

So as long as looked after they are strong engines

I assume that it is an E34 - it is a big car and an M20B25 is the smallest powerplant i'd want to have under the bonnet, the 520's were a bit underpowered and the early 518's hmmmmm

[kiwi6539 3]

Yes looking for E34 525i or 535i. But will use it everyday so thinking the M20b25 might be a bit better on fuel.

Just want enough power for some fun when I want it. but won't cost me loads on fuel.

[Creaver 55]

Yes looking for E34 525i or 535i. But will use it everyday so thinking the M20b25 might be a bit better on fuel.

Just want enough power for some fun when I want it. but won't cost me loads on fuel.

Personally i'd go for the 535. The fuel consumption shouldn't be too much worse, and it performs a hell of a lot better than the 2.5l

[BM WORLD 1266]

if you want a 525i get a M50 one . dont bother with the M20 in a e34 (to heavy)

[Eagle 1545]

if you want a 525i get a M50 one . dont bother with the M20 in a e34 (to heavy)

I agree. The M20 in the E34 is pretty sluggish compared to the M50. Like its been said might as well get a 535i manual. It ain't that much worse on gas,heaps more powerful and no timing belt to replace either.