M20 2.8 stroker vs M50b28?

[Wh33lhop]

We had a few alloy M52s over here. Also, M50B28? I take it the OP means M52.

[Stephen]

a proper and thorough m20 build will cost more than an m50 swap (that hasnt had a build), yes, but that is a little of a apple to oranges comparison. if you want a more modern efficient motor then go for the m50. Then agian, im not really into e30s for efficiency and modern engineering (not like obd1s m50s are exactly cutting edge)

Theres other things too, like the fact that your car presumably already has an m20, and that you loose even more already-bad oilpan clearance with a 24v.


On the other hand, m20s are just about free and a proper build of an m50 will expensive too, due to the fact that there are so many more parts in a 24v.


Me personally, i will probably stick with an m20 due to simplicity, and my e30 just isnt a performance build, but oilpan clearance is already slim. However if i was building a quick DD type car, a 24v would be higher on the list


edit: just saw that you have the 1.6 m10. That would put the m50 a little higher on the list for me

[Delraco]

The setup I would go with in my attainable perfect world would be an alloy M52B28 block with a NV M50 head. Cammed and supercharged would be nice..

Don't get me wrong I love my M20, but NV M50 is just about as simple without the Vanos headache.

I thought that the M52's were all iron blocks in the US anyway..but that's beside the point!

[bades2001]

Aren't US M5xs iron?
If they were Al it would be a very worthwhile conversion I think..

If im not mistaken only 2.8 Z3's had a m50 alloy block. Pritty sure his is an Aussie/euro m50 anyway.

[Drew325is]

Yeah I thought the Z3 2.8s in the USA were alloy....and yup, mine is a euro alloy M52B28 (well, actually the motor itself is ex Jah-pan)

[einstein57]

ever herd of a timing belt break on a m50...or a rocker snap on a s52?

Ever hear of an m50 with over 300k original miles likes its a normal thing? Or how about a cheap m50 rebuild? The only benefit to an m50 in my book is gas mileage, or going insane turbo whp. Otherwise your just trading off negatives.

I'm going 2.8 m20 myself. Another member had some pistons made for the eta crank that brings it to 2.8 with the stock 8.8:1 compression. That and a nice cam, IE hd rockers, and a nice turbo should net me 350whp on 15psi. I think it would probably pump out 180+whp NA with 19lb injectors depending on your cam and tune.

[trackjunkie21]

Friend of mine has a 2.9 stroker 325is. Don't know the exact specs but he makes around 205whp. Puts his s50 m3 to shame. Sounds like a dtm car.

[reelizmpro]

We're missing a key thing there. He's starting off with a 316i. So no matter what, he's looking at doing a swap of some sort.

[Jparkr]

I have a 2.7 M20 with 272 cam regrind and I love it to death. It is torquey and powerful and basic. It is faster than my buddies M50tu as well but that may be because of weight difference between his E30 and mine.

I am currently building an M50nv w/ s50 cam grinds as well and I am looking forward to it but only because it is going to be my daily driver.

As of right now I would take an M20 over an M50 any day. But then, after I start driving my new car who knows how I'll feel.

I would take the M50 if you are going to DD this thing. Take the M20 stroker if you want to have more fun with it.

[Stoner Sam23]

My vote is m20. 24v are superior but they lack raw power

[nando]

it probably costs less to build an M20 than to do a similar build on an M50. aside from having one less cam, actually buying things like pistons, rods, etc. is about the same.

Of course a plain swap is cheaper - people are throwing in used, high mileage engines from the junkyard and comparing costs with a fully built engine. duh, that's going to be cheaper. ;)

but he didn't ask what was cheapest either. The M52B28 is a fantastic motor stock - so if you're going to leave it stock, that's my vote. it would be a pretty fun/practical DD that way. If you're going to build it though, I don't see the point of a "stroker" M50. BMW already made one, it's called the S50/S52. plus you already have experience with a properly built M20 - something most here do not.

[e30rapidic]

I have a brand new 2.8 M20 in my 5 speed e30 has 19# injectors, big six maf, 4.10 diff, BMP chip and i swear my 6000lb F150 Super cab w 33's is faster. Its has a programmer, intake and exhaust only. Its pushing close to 370 hp now...but still a damn truck!!

Its more powerful than a 2.5 M20, especially on the highway but its just not right having a truck that's quicker!!! its S52 time or something!

[trackjunkie21]

I have a brand new 2.8 M20 in my 5 speed e30 has 19# injectors, big six maf, 4.10 diff, BMP chip and i swear my 6000lb F150 Super cab w 33's is faster. Its has a programmer, intake and exhaust only. Its pushing close to 370 hp now...but still a damn truck!!

Its more powerful than a 2.5 M20, especially on the highway but its just not right having a truck that's quicker!!! its S52 time or something!

almost 400hp against about 180whp. That's like double the power. Now do you know why it's faster?

[M42Power]

disagree 24v or nothing, everything about the m20 sucks...from the oil pans that leak to the rockers that break and from the timing belts that snap to the oil return tube and there vacuum leaks....I could go no

worst motor bmw ever built....and the only one with a tbelt

The m40 was by far the worst and it had a belt, plus inumerous head problems.

The m20 is not that bad, if you had the m40 in america you would see what a bad engine is.

[M42Power]

The m40 was by far the worst and it had a belt, plus inumerous head problems.

The m20 is not that bad, if you had the m40 in america you would see what a bad engine is.

If you wouldn't change the belt in 24k miles, you could say goodbye to the engine, the hydraulic lifters would prematurely fail and the list goes on. Oh and it was gutless.

Compared to it and many modern engines the m20 is still a good engine. Look at the 320d's for instance. And all the expensive break downs modern bmw's have...

Well, im happy with my m42...