which 24v engine is best for boost

[32VALVES]

I would like anyone to chime in on this...
Should I use a M50 or S50 now so later I can bolt up a nice 66mm turbo on it?

this is using stock block not going inside of it...

[nando]

IMO M52B28 > all

[SamE30e]

If you're running stock internals M50nv....

[bloodshot-e30]

for all stock internals the M52B28 can go 19psi
the M50 can do 18 and the S50 and 52 can do 17

[Fusion]

I'm thinking about buying a used turbo kit (16th km), which has a spacer between the head and block to lower compression and I've read that even the stock pistons will take a lot of boost. Of course more boost = more power = shorter engine life but 350ps should be safe.
The kit was originally mounted by Kerscher in Germany into an E39 M52B28 but I'd be setting it up on my M50.
So I would like to add my question - how much beating will a M50 take? How many boosted M/S-50/52 swaps are there on the forums?

[32VALVES]

I have a chance to buy a m50 or s50, and of course dthe m50 is cheaper but this next year I should have my vw gti sold and have some of the turbo stuff of that to put on what ever I have. People say if I turbo any motor it should be the m50...

[Fusion]

I think a huge advantage to the M50 is that if something does go wrong, finding parts or a block or whatever isn't such a (costly) problem.
If you guys know any good M50 turbo build threads (even E36) please post em up.

[bloodshot-e30]

BMWSOB on e30tech is sellin his turbo kit for 2000 for his M50 and made over 800 HP
but if you are boostin an M50 i would do that over an S50 or S52 anyday...
and its also easier to tune

[lennon]

there are tons of boosted 24v motors on bimmerforums. i would look for info there.

[Iain]

IMO M52B28 > all

Just so long as its not a Euro M52 :(

[nando]

If you're running stock internals M50nv....

why specifically? i'd think the forged crank and meaty pistons of the M52B28 are worth something.

but if you are boostin an M50 i would do that over an S50 or S52 anyday...
and its also easier to tune

errr what? other than more displacement they're the same motor.

[nando]

Just so long as its not a Euro M52 :(

is that the M52B25 with the choked out top end making ~170hp?

[M-technik-3]

US got predominately cast iron block M52's and our Z3's got a few aluminium blocks.

[rThor432]

Just so long as its not a Euro M52 :(

You referring the little 2.0-2.3 litre lumps they made? Yeah, those must suck..

for all stock internals the M52B28 can go 19psi the M50 can do 18 and the S50 and 52 can do 17

Where did you (or Active) pull those numbers from? The difference of 1 psi sounds like someone is splitting hairs for no particular reason. And those numbers say nothing about how long the engine will last at any of those pressures. I can run a stock S52 at 30 psi, just not for long. I don't think any of those motors will hold together at 17-19 psi for long enough to call them "reliable", especially on the track.

[Iain]

is that the M52B25 with the choked out top end making ~170hp?

You referring the little 2.0-2.3 litre lumps they made? Yeah, those must suck..

Nope, the M52B28 as used in the E36 328i and - I think - the E39 528i. It was the first-gen version, not the M52TU that came later, and had the lightweight block, etc.

I don't know what pistons/rods we got in our fuh raze M52B28, but I'm about to find out seeing how I've now got one in the garage needing a full rebuild.