what is a M50 or S50 and what cars did they come out of?

[Super Eurobeat]

please be specific instead of like E28, E30 etc...
year and number please

also why is it so popular?
and is it a direct bolt on for you E30 guys?

[ZinRot325i]

M50 is a DOHC I6 that came in e36 325i, 325iS from 1992-1995, and in e34 525i from late 1991-1995. 190bhp. Variable valve timing from late 1992 on.

S50 came in e36 M3 from M50 years. Basically the M50 but with a bigger bore and better internals. 240bhp.

They're popular because they bolt to the Getrag 260 with little modification, are fairly easy to find, and can be tuned easily.

You can fit it in your e28. I'd put a manual transmission in if you don't have one yet tho.

[Super Eurobeat]

oh so i take it the head wont just bolt on then...
yeah mines a 88 528e with a getrag manual 260
i heard that the DOHC heads has problems is that true?

also isnt the ONLY way variable valve timing to exist is to have a solenoid PHYSICALLY push the cam to the side and have a lobe that gets progressively bigger to the side?
i always ask and people just say stupid things like "oh its just variable" like you are expected to know what the hell that is.

Cause on Ferrari's the cam physically slides to the left and right via solenoid.

[ZinRot325i]

No the head won't bolt on, cooling passages are different.

Those engines are pretty solid, the top ends though are a little more fragile than the M20. But they'll last 200k plus all day long. Yes, the cam moves.

One of the tuners made a DOHC head for an M20 but only a few exist and the template was destroyed.

[FredK]

Those engines are pretty solid, the top ends though are a little more fragile than the M20.

Um, 'scuse me? Broken M20 rockers anyone?

The M50 has a bulletproof top end. The 10/95 and earlier S50s have slightly higher failure rates for the valve retainers, but there are updated design retainers available for the head which make this point moot. With the updated retainers, failure is very rare.

If you take the engine beyond 6800 rpm regularly, the <11/95 retainer issue may be a problem. But, if you nip it in the bud with updated design hardened retainers, you're all set. Of course, getting to the retainers is another issue, but it's not impossible for the DIYer.

[silverfbimmer]

Um, 'scuse me? Broken M20 rockers anyone?

.

Guilty....

[SchnellerVert]

Um, 'scuse me? Broken M20 rockers anyone?

The M50 has a bulletproof top end. The 10/95 and earlier S50s have slightly higher failure rates for the valve retainers, but there are updated design retainers available for the head which make this point moot. With the updated retainers, failure is very rare.

If you take the engine beyond 6800 rpm regularly, the <11/95 retainer issue may be a problem. But, if you nip it in the bud with updated design hardened retainers, you're all set. Of course, getting to the retainers is another issue, but it's not impossible for the DIYer.

Bulletproof nope just more durable. M30 = Tank engine. Vanos units are prone to failure as they get older.

[Stu]

Bulletproof nope just more durable. M30 = Tank engine. Vanos units are prone to failure as they get older.

Tank--as in weight? 75-80 pounds more over the front axle compared to an M50? Considering what it takes to put similar power down out of a 3.5 compared to a 3.0 m50....I don't see why you'd swap one in. Unless it's being setup with a big turbo and live axle for 1/4 mile. :shrug:
My $.02

[SchnellerVert]

Tank as tough and durable.

[b*saint]

No variable valve timing can be used via a 2nd rocker arm and a 3rd lobe activated with oil pressure i.e. Toyota VVTi and Honda VTEC.

[Hawk]

Tank as tough and durable.

No joke. But then again mine sees maybe 5k once a week and 2-3k most the time they are cammed for midrange tq reving an M30 hard is pointless.

[erik325i]

S50 came in e36 M3 from M50 years.

Well, accually the s50 only came in the '95 m3.

-Erik

[moatilliatta]

s50 has difrent better flowing head.... am i right?