S50 Engine Conversion

[ahmed qadr]

Hey Guys ,



i 've recently done the S50 engine to Non BMW car , engine Runs great idling very smoothly . but in term of speed from 0 to 50 km.h is pretty well . then it kills down .

hardly can i go from 60 to 80 km/h revving 3000 RPM which I know for 5 speed Manual with s50 its not normal . see your self in Video in the link .

so any Suggestion where to start ?

not Engine had 90k on it when purchased .

[bmwdirtracer]

To even begin considering your question, we need more information than "S50". Are we talking about a U.S. spec '95 S50B30, or a '99 S50B32 in Euro Spec? Later model DME's will likely be looking for vehicle speed or other inputs from other computers.

[MauiM3Mania]

To even begin considering your question, we need more information than "S50". Are we talking about a U.S. spec '95 S50B30, or a '99 S50B32 in Euro Spec? Later model DME's will likely be looking for vehicle speed or other inputs from other computers.

Or a '95 euro S50B30? A number of variables, so to speak.

[bmwdirtracer]

Yes, indeed.

Ahmed, MauiM3Mania and I installed a Euro S50B32 from a '98 or '99 Z3M into his '99 U.S. M3 S52B32. The car ran perfectly from the very first moment we provided fuel......because we spent dozens of hours studying hundreds of pages of wiring diagrams for BOTH cars, and accommodating the differences. The differences were MANY, so it's hard to imagine how much differs in your "non-BMW" swap.

You know, telling us the car the engine went into just might help a few members who happen to deal with whatever it is. No promises on that, though.

Fuel pressure? Exhaust flow not restricted? Intake airflow? ASC or DSC not preventing full power? (I see your temp gauge doesn't work....does the DME know the coolant temp and intake air temp? Do you have trouble codes in the DME?)

Not that I have a lot of access to Euro diagrams, but I cannot even begin to guess what might be wrong without knowing much more about the conversion details...what engine, what computer, what recipient, who did this swap?

By what means are you able to converse with the DME?

(If you can't, you're in deep trouble)

[ahmed qadr]

well first , thanks for kind reply . in term of information's i have all this information as bellow :

engine " 95 S50B30 OBD 1 ,
DME : Number is " 0261 203 506" On the DME , " i am not sure if we have correct " .

Original BMW M3 Intake intake air temp is connected with DME ,

exhaust is full steel Custom make .

for ASC and DSC i dont have any info about that .

well Coolant Temp is connected to DME but in the Cluster is just reading like 60 degree . because Cluster is original of car which is OPEL OMEGA 1993 ,

i did that swap and took me 3 months to finish all set up.
i dont have any info about how to code the DME .

also the differential is from M3 bmw as well .

Thanks guys for helping and i am so sorry to tell you this little information i know .

Notice : this is my first swap on BMW engines .

[bmwdirtracer]

When you installed the engine and DME, did you use the entire engine wiring harness? In other words, do you have the 20-pin diagnostic plug anywhere under the hood? If so, then you can find a good BMW shop to read the codes in the computer. (I see that Erbil is a city of ~1,000,000 people, SOMEONE's got to have an old BMW diagnostic computer!)

It will be exceedingly difficult for you to keep this engine running correctly, if you have no way to talk to the DME. Even on this old an engine, the DME can show a good amount of live data, when connected to a decent diagnostic tool.

Of course, you should confirm fuel pressure, make sure that the throttle blade is opening all the way, make sure that a rat hasn't built a nest in the intake.. Do you have misfires ?

If I had to make a guess, and I was sure that the air intake was unclogged, and the fuel pressure is correct -- I'd guess that the cam sensor is not getting information to the DME. IF this is true -- and it's absolutely nothing more than a guess -- it could be a bad sensor, an unplugged or faulty wire, or even a wire that's been plugged into the wrong spot. (And that brings us back to having a diagnostic tool, again. The diag computer would give you a code, immediately, if the cam sensor signal is missing.

By the way, how quickly does the engine start, when you turn the key?

[WadiM3]

Erbil is the capital city of my country if it will ever become a country lol. They laugh at E36's or any car that is not 2012 and above... 97% of cars you see over there are Toyota Land Cruisers. Kurdish people are very far from diagnosing things they just love to assume and throw parts at the car which is probably going to make things harder for OP. Ahmed do you have a Euro S50b30 or a s50b30 US Spec?

[bmwdirtracer]

Thanks, Mohammed. I was thinking of you, as I looked up Erbil, and found it was the defacto capital of Kurdish Iraq, and is one of the oldest cradles of human civilization.

As to whether " Kurdish people are very far from diagnosing things they just love to assume and throw parts at the car which is probably going to make things harder for OP."....well, I don't know, Mohammed. YOU can say that, (just like I can say that New Yorkers are "pushy"), but I think that your quote pretty well describes a whole lot of Americans that use these forums.

Welcome to the forum, Ahmed. The members here are from all over the world. I am very happy to know that there is someone doing something as unique as an early '90's BMW to Opel engine swap, half a world away.

[ahmed qadr]

well Guys , i Installed Engine with DME and Entire Harness that came with Donor car , and yes I have 20-pin diagnostic plug , and yeah we have good BMW Shop to check the diagnostic,
l that was my main concern before i go diagnostic it , i wanted to know what is the issue by my self .

- i don't have any misfire , and engine is starting with very First ignition when key is turned .
for sure i will diagnostic with tool , i will follow the result .

[ahmed qadr]

Hey Mohammad , Nice to See you around here , i know they Laugh with E36 and they care about high model cars , but not me . i've learned too many things during works on the BMW's so far .

but there is one thing you have to care about in place where i live , economic crisis we have to buy reliable cars for example i have Toyota Corolla as well . and working with high temperature degrees .


i've managed half way to open a garage for Car Services , engine swaps , turning as well . and i will not assume and throw parts . it will be different for me and some guys i know .

but again very nice to meet you . and the engine is S50b30 95' OBD 1 - Euro Spec .

- - - Updated - - -

And Again very nice to meet you guys


this is my FB as well : https://www.facebook.com/Ahmedqadr

[WadiM3]

Nice to meet you Ahmed, I live in London, United Kingdom. I'm very happy to see the Kurds have advanced.