Ultimate Street Sleeper - Mercedes W124 'Superturbodiesel'
Discussion
LocoBlade said:
Not sure I understand how it can rev that high either. I always thought diesel engine rev ceilings were limited on revs by physics. Diesel burns much slower which I thought was the main reason they never rev much higher than ~5k, plus a lot higher compression means heavier internals and more stress on the crank / pistons as the revs climb.
I think that at 3 bar anything burns quick enough!Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
Gorbyrev said:
What a pleasing lack of DERV haters on this thread. Lovely beast you have there. How do you stop it starting to use the engine oil as fuel at high revs and lunch itself as it revs out of control?
That's nothing to do with revs. That's called a run away and usually happens when a turbo goes and the engine starts to ingest it's oil. Ordinarily there's no engine oil in the cylinder 
Black smoke racing run with a blower aswell 
https://www.youtube.com/watch?v=KRhl182UAGY
https://www.youtube.com/watch?v=KRhl182UAGY
Edited by klunkT5 on Saturday 6th February 00:15
If you look at the superturbodiesel forum you'll see what is possible with this engine. From five minutes googling, it appears that 7,000rpm and 3bar are fine on the stock engine but above that you need stronger valve springs. Even in absolutely bog standard normally aspirated form, the OM606 is a curiously high-revving diesel: it doesn't really come on strong until 3,600rpm and from there it pulls hard to 5,400rpm.
xjay1337 said:
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
Max_Torque said:
xjay1337 said:
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
8000rpm does seem crazy but I can't see why making that power is any problem.
Mercedes borrowed the diesel OM603 crankshaft and con-rods for the petrol M104 C36 AMG engine, I was pretty surprised about that when we stripped down a '36 engine 10 years ago.
Max_Torque said:
Hmmmm, so let me get this right. Professional engineers, with degrees, years of experience and the best backing in the world can't break the laws of thermodynamics, and yet, some random guys off a forum can............
Degrees....... Lol. Why is it that a Diesel engine cannot reach 8k rpm, and this one can't make 500+?
Max_Torque said:
xjay1337 said:
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
Max_Torque said:
xjay1337 said:
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
a. Why revving this diesel to 8000RPM, breaking the laws of thermodynamics?
b. Why is this power figure impossible in this engine? (Dyno lottery accepted)
Genuine question, I have read some of your previous posts on similar questions, and they were very informative.
Edited by QuantumTokoloshi on Saturday 6th February 11:50
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
8000 rpm seems a bit optimistic, they seem to manage 6000, but these things seem to make some serious power, the engineers you mention in your other post have to make the car easy to live with, reliable, quiet, tractable, economical, pass regulations and not belch clouds of smoke that the Flying Scotsman would be proud of.The guys who tune these arent constrained by that, the OM606 seems to be regarded as very strong and over engineered so fit a larger turbo, replace the fuel pump, crank up the boost and the fueling and it holds together and makes big power, it doesnt break any laws of thermodynamics, not sure on the actual figure but there is a lot of evidence for some pretty big numbers, it is kind of how racing trucks started, normal rig, tweak the boost and fuel and off you go.
Max_Torque said:
Hmmmm, so let me get this right. Professional engineers, with degrees, years of experience and the best backing in the world can't break the laws of thermodynamics, and yet, some random guys off a forum can............
You are missing one vital piece of information, try:Pre Combustion Chamber
Looking again at the dyno chart on the first post, it finished at 5,800 rpm. We only have the op's word that it revs to 8000. It might be simply that his tachometer is not accurate at those revs.
My knowledge of the diesel cycle is rudimentary at best but from what I recall, it's the combustion phase of the cycle that is the limiting factor in how quickly an engine can rev. It was 20 odd years ago though when I studied it so could well be remembering it wrongly.
My knowledge of the diesel cycle is rudimentary at best but from what I recall, it's the combustion phase of the cycle that is the limiting factor in how quickly an engine can rev. It was 20 odd years ago though when I studied it so could well be remembering it wrongly.
Edited by Super Slo Mo on Saturday 6th February 11:20
Twoshoe said:
I wonder how it handles - my old W124 E320 struggles with considerably less than half that power! Any suspension/steering mods?
I wondered about that too! .... especially having owned several 4 cylinder petrol W124's that felt like they had 100bhp on a good day! Respect though .. its awesome .. an incredible testament to the engineering in that standard engine. 
Max_Torque said:
xjay1337 said:
Max_Torque said:
8000rpm. i think not. It ain't even gonna go past 5500. There's also precisely zero chance of it making a real 550bhp.
Why is that? Plenty of VW diesels have been modded to run that kind of RPM.
Not so much on common rail modern stuff but the older injection pump type diesels it's not uncommon.
Is it a fake 550bhp? Or are diesels just not very fast.
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