Has the M50 NV 2.9 Stroker EVER been completed?

[xxxxxxx]

I've been reading thread after thread this evening on the subject.

No one ever seems to complete the build.

Goals are set. Parts are acquired. Parts are sold. Thread dies.

I know a swap may be cheaper and easier.

But has anyone ever completed it, successfully?

[gdavid]

Which mix of parts are you referring to?, most people do (or at least start) the 2979cc displacement using m54b30 parts. I just finished my m52b30 single vanos and I don't see why non-vanos would be any harder. Alone it is not worth it in terms of performance but if you are rebuilding the engine anyway or building up a custom build it with other stuff in mind it is kind of fun. I'm still sorting out a couple of things but I expect to be successful. I believe spydergod has a m50b30.

[xxxxxxx]

That's kind of what I am trying to figure out.

I am curious about the max potential of the M50 non-vanos for street, without FI, and what arrangement of parts gets you there.

[spyderg0d]

Vanos is always better than non vanos. Unless your new to tuneing, that is if your doing it yourself at all. The arrangement of parts are the same as the tu engines. Its best to use the m54 Assembly together rods, piston, crank with new properly fitted bearings, gaskets,guides and seals.
The larger displacement wont really net you any gain until its tuned properly. Then your looking at about 235horsetorques. Personally, I decided a 3.91 diff and a zf transmission with a m5 clutch kit to really make use of the torgue rather than the horsepower. But I also went with the m54b30 intake cam for mildness, on top of a dinan big bore tb, and supersprint exhaust. I'm past a stock s50 by much ponies and pushes and eat a frens stock 98m3 like breakfast toast.
Although, dont have much on the new minivans until I clutch the SC.

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People never finish the threads because once they have the engine done there is no more questions. Plenty of youtube 1st start vids tho.

[xxxxxxx]

Vanos is always better than non vanos.

Let's not derail the thread plz, thx.

Just looking for answers on stroking the non-vanos m50.

[jr02518]

Ok, I'll ask, what is the engine going to be installed in and what class or group will you be running in? You know, why?

I have a NV M50 in a 2010 vintage NASA GT2 E30 running a Getrag 260 transmission chipped to produce 180 or 190 hp based on available fuel. The car came with a 4.10 LSD, acting more open than limited and now has a 3.73 that works. My limit to getting the car to hook up is tires. The car is set up to run 225/45 15's on seven inch rims, the fenders are rolled and will not be cut.

But having more torque, to come out of the corners, that I can embrace. I'm looking forward to how this works out.
David

[pbonsalb]

Is the OP trying to stay NV to be in class rules or save money? I’d run it if I could.

[xxxxxxx]

Just street use. I have a NV so that's why I am curious about it.

[spyderg0d]

Out of all the info in that post, you chose that one small sentence to focus on and just not acknowledge the rest?
Vanos or non vanos makes no difference to stroke out. The blocks are the same. I said vanos is better becaise vanos will result in more torque and more horsepower, thus a m50b30 engine wont have as high of a rating as a m50tub30. Since your not vanos you will need 2 nv intake cams, 1 ran on the exhaust, or special order high lift camshaft. The best bet is to buy the dinan m50b25 full package, get a vustom tune with thestroked engine.

[xxxxxxx]

OK cool, so my list is kind of looking
like this at the moment:

M50B25NV Block + Head
M54 Crank $200
M54 Con Rods $250
M54 Pistons
M54 Piston Rings
M54 Bearings
M50 Seals
Move M5Bb25NV intake cam to exhaust
New schrick cam for intake (or dual m50 intake cams? $150)
Head gasket (stock)
Head bolts
Custom tune
Headers
Exhaust
Ball hone

Consider
Increasing compression by shaving head
Porting head


If I want to run 91 octane (that's all we
have around here), then I need to figure out
the correct HG thickness that would optimize
compression, avoiding detonation...

Would RWHP be comparable or better than a stock S50?

[spyderg0d]

91 octane is up the alley.
You want m50 seals. Not m54 seals. M54 seals fit the m54 timing case and rear seal, you will be useing a m50 block and need seals to fit the m50 timeing case and rear seal.
The bearings are the same across all bmw model engines for the most part. And you want to buy them in the correct sizes to fit the crank to the block. Research on how to measure those specs, do the math to find the bearing clearances, and buy proper bearing shells accordingly. This is the most important part next to proper piston and piston ring fitment. The rest is childs play. Also you will want new piston rings to match the piston.
The power isnt great ran on a stock 413 dme. But its certainly better than a 2.5l. The tune makes it worth it. Stock head gasket is fine if your not fi. Compression wont be much higher than a 2.8l. I think it was somewhere around 1.5.11 but I cant accurately recall with certainty.

[xxxxxxx]

Awesome. Added those revisions to the list.
Good call on rings. Also going to add a ball hone.

Any idea of the ballpark RWHP with this setup and a tune?

[spyderg0d]

I think i seen a otherwise completely stock m52b30 obdll dyno chart at around 255whp and similar torque. I think obdl is more hp and less torque if i remember the discussion right.

[gdavid]

I think i seen a otherwise completely stock m52b30 obdll dyno chart at around 255whp and similar torque. I think obdl is more hp and less torque if i remember the discussion right.

I would love for this to be true, (primarily because I have one) but I don't see how it is possible, with a stock HG it has a similar or lower compression ratio than a S52, less displacement and less aggressive cams. I would expect an "otherwise stock" m52b30 to have similar output to the m54b30 which has a better intake manifold and the same displacement. Mine is far from dialed in yet and running about 10.3:1 compression with a M54b30 intake cam (non-zhp) and m52 intake manifold running on the stock tune (and I haven't been able to clear adaptations yet). I wish I knew someone else nearby running obdII to compare notes with before I pursue tuning options. I'm also running cats and full emissions equipment.

[spyderg0d]

You do realise the hp rate is relevent to the rpm right? A stock s50 is rated at 240hp at 6k. About 280 at 7k. And about 290hp at 7100.
And an s52 is a s50 with a better intake and exhaust side variable valve timeing for increased torque with close power specs.
A m54b30 is 230hp at 5.6k. Probably close to 260at 7k. So... It makes sense if you look at it objectively.
The mechanics of an engine are useless if the ecu is incapable to efficiently rum the engine. You can throw every bolt on on an engine, wont make it really do anything better until the ecu optimises its map to make use of mods.

[pbonsalb]

S52 does not have better intake or better variable valve timing than an S50. It does have better exhaust manifold and midpipe.

It is true that cams can extend the power and and that higher rpm breathing adds power. Apart from forced induction, more rpm is the way to get more power out of the same displacement but you need cams and the more radical the cam, the more trade off with bottom end power.

[spyderg0d]

Shucks, I was thinking the m54, with dual vanos and disa intake. ...

[pbonsalb]

Yes, M54 is dual vanos and two stage intake, but catted exhaust manifold and only 3.0L vs 3.2L of S52 and possibly not as durable though lighter aluminum block. I think the S52 is great to turbo in the 500 rwhp range. Neither is really a great high rpm motor. 7200 is a good maximum with aftermarket cams.

[spyderg0d]

Yeah. I think thats what keeps people from just swapping m54 and going turbo. That aluminum block is a real bummer for power. Ive seen about 12 of those in the yard from rods being sent into the dirt. Almost always number 1 or 2. Always score the crank pretty bad and make them useless.

[gdavid]

I've seen about 12 of those in the yard from rods being sent into the dirt. Almost always number 1 or 2. Always score the crank pretty bad and make them useless.

What do you think causes the rod failure? I've heard their oil control rings are problematic and they can develop oil consuption. I'm curious to know if the blown motors you have seen were run out of oil to the point of losing oil pressure or if it is something else. I would expect the main and rod bearings at the front of the block to have the most oil pressure, so that probably sinks my theory.

[spyderg0d]

What do you think causes the rod failure? I've heard their oil control rings are problematic and they can develop oil consuption. I'm curious to know if the blown motors you have seen were run out of oil to the point of losing oil pressure or if it is something else. I would expect the main and rod bearings at the front of the block to have the most oil pressure, so that probably sinks my theory.

Turbo.. Rod death by turbo. You can tell by the missing exhaust manifold, its always a 330 car, the random vacuum tubes rigged into the intake manifold, and the lack of injectors and fuel pressure regulator. They blow the engine, take off the turbo setup for resale or use and junk the car.
My wifes 03 325i, I boaght for a grand in 2015 with bad crank bearings. Bought a yard engine with 80k on it, it now has 120k engine, 140k car, eats a quart of oil about every 3k miles.. Its annoying, the exhaust smells like burnt oil on cold days or rainy days. On top of the cvv being a complete pos (even brand new) that will freeze up if not pampered to on consecutive below freezing days doesn't help. I keep it in check alittle better by useing sae oil, it absolutely ate through synthetic oil.