Reply With QuoteI was told by my tuner that the supercharger is maxed out at 5800 so if you go higher you cavitate the air and generate more heat
Guys,
Anybody know why the M111 C230K engine's rev limit is at such a modest 5800? Is it due to cam timing, a limit on supercharger speed or piston stroke?
Thanks in advance.
JJJ.
I was told by my tuner that the supercharger is maxed out at 5800 so if you go higher you cavitate the air and generate more heat
Yeah Mike, that might be a reason alright. If that is correct and considering these over sized crank pulleys being fitted with seemingly good results, maybe Mercedes were being conservative about the 5800 rev limit?
Last edited by John Jones Jr.; 04-15-2013 at 12:27 PM.
JJJ.
Thats a good point, mercedes doesnt disclose anything to find out
I'm wondering now did Merc set the 5800 limit for hard autobahn use i.e prolonged high speed, something like 120mph plus? If so, it would seem to be even more of a justification to improve the cold air feed to the S/C and also fit a better intercooler.
JJJ.
At 120, I dont think my car is running close to 5800…
No it wouldn't be, as top speed is 140+mph I understand. The point I was trying to make is, prolonged high speed use or more to the point prolonged max rev use, Mercedes decided to keep max rev limit at a modest 5800 to keep excessive heat build up occurring in S/charger?. I don't really know, just making guesses but would love to know as I'd really like to improve on the standard power without spending mega bucks.
Anybody on here know or tried water injection, pre compressor? I considered a water spray system for the intercooler but again I'm unsure of the ins & outs.
All comments & advise greatly received.
Keep on Rocking!
Last edited by John Jones Jr.; 04-15-2013 at 08:15 PM.
JJJ.
meth will raise the octane theoretically to 116. it also will cool the charge down a good amount. it would be good if you were running higher boost out of the supercharger to prevent detonation.
2014 Black Sapphire BMW 328d xDrive
1997 Brilliant Silver C36 AMG 183k miles (SOLD)
1994 Spruce Green C280 176k miles (SOLD)
Drexel Business '11
they would have set it so low because they were able to obtain enough power with out revving it so high, therefore increasing engine life. the engine could handle a lot more.....
Interesting you mention that. I was just looking at a specialist site for water/met systems and if their figures are to believed it's possibly well worth investing in but, cost would be a slight issue if I was going down that road. Pump, Controller, Tank, Loom, Injector, Piping etc all add up to a pretty sum. Now I'm sure a home made job could be rigged up and save a lot of $$$, just it's hard to beat the professional set up imo.Originally Posted by anf6789
JJJ.
JJJ- my remark was more alongs the lines of what Dearlove said. Not trying to brag. I do recall my 280 performing the same though.
Understood Denlasoul
JJJ.
I don't altogether accept that or rather I've my doubts. We are in agreement that the engine could handle or produce more power safely without affecting it's lifespan so it would have I presume, in theory very easy for Mercedes to have given the C230K more power if it really wanted to. I suspect that it was a marketing decision or cost reasons that power was pegged @ 193PS & 5800RPM.
Anyway, regardless of what I think, presume or suspect, I'd still really like to know the exact reason why the rev limit was set @ 5800. Mike51809 made a good point about the S/charger (or maybe even it's installation, come to think of it) being max'ed out at any higher rev's as far as Mercedes were concerned, if this is the case why is it max'ed?. According to Eaton themselves the M62 is suitable for engines between 2.5-4.0lt's, so that implies that the M62 is not max'ed out but as I mentioned earlier would it more likely that the installation is not up to the job thus there's no point in having a higher rev limit than 5800?
I don't have the answers, thus all my questions! Sorry.
Rock on!
Last edited by John Jones Jr.; 04-16-2013 at 01:26 PM.
JJJ.
the rev limit has nothing to do with the s/c speed, they could have made what ever sized pulley they wanted for what ever rpm they wanted.
If they could have gotten enough power by 4k rpm they would have limited it there. It would have been the magic number the engineers came up with for the perfect compromise of power/drivability and engine longevity
the faster an engine spins, the sooner it dies. That's half the reason the diesel merc last so long...
Your comments still don't enlighten me, I'm sorry to say. Also, it still doesn't answer the original question I asked simply because most forced induction engines of it's era have higher rev limits. And I for sure wouldn't want a narrow 4k power band from a petrol engine, may as well just buy a diesel.
Lets say we agree that rev limit & S/c speed are not connected - as you say pulley size on the engine & S/c can be tailored to suit. So, that automatically eliminates the S/c as having any bearing on the engines max rev's. Then, would I be correct in saying, all we are left with is either the installation set up of the S/c (i.e. pipe work design, S/c location, Intercooler efficiency etc), the Cam timing or the piston stroke? From what I recall, as I haven't got the figures to hand, the bore/stroke was O.K.- the engine is not considered a long stoke design. So, that leaves the Cam timing and/or the installation set up. Any ideas if the standard Cam timing could be limiting the rev limit?
Last edited by John Jones Jr.; 04-17-2013 at 03:02 AM.
JJJ.
Get a tune and take the rev limiter off. Bam!
The m111 has so much potential...
Funny you mention that Mike. I've been offered this...but no raised limiter. Bull or what?
Mercedes C 230 Kompressor 193 hp>220 hp 280 NM>340 NM
''30 Day Trial When an ECU is ReMapped for Performance or Economy we offer a 30 Day Trial. If needed we can Revert your ECU back to Standard and offer a full refund''.
JJJ.
What company is it? I know a place called speedtuningusa where i got my tune and they do custom tunes too... But with the rev limiter im not sure honestly, talk to pagz or slammedc maybe, they have done alot with the m111
It's well respected family run company here in Ireland, they are exhaust specialists too and well known within the tuning scene here and on top of all that they are great to deal with too. Now, having said that, they are just buying in the electronic know how, they remove the ECU, down load the info and after that I'm unsure of where the download is sent too. What they have told me is the new map is not a basic generic one, i.e. the map will be custom to my engine? Will keep you posted. I've still doubts about a 27hp gain. But I'd be happy with 10hp and improved drive-ability.
I've another plan hatching too. I've just purchased a C230K crank pulley from Germany (€60 delivered), so I'll be giving that to an engineering shop to see if they can increase the diameter. I'm hopeful, fingers crossed.
JJJ.
ah i see what your asking,
Okay so whats stopping the engine revving harder? besides the rev limiter? nothing....
i think with the stroke at 3.48" it reaches a mean piston speed of 3500 FPM at only 6034 rpm...
i say 3500 because i remember hearing that that the max you want to go with stock cast pistons.
but this is a little contradicting because if you do the same math for the c36 a 'safe' redline is 5700 or 6600 if you use a higher 4000 fpm, when in actual fact the limit for the c36 is about 6800.... but that engine uses forged everything....
I'm glad now that you understand what I'm actually asking.
Still, I'm doubtful the 5800 rev limit has anything to do with non forged internals, actually I'm almost certain my 2.5-16 has cast pistons and that runs to 7250. I'll be speaking to a guy who's been involved with Merc's and has massive experience (40 years of it) and see what he says. I'd really like another 500rpm without any disadvantages or associated problems.
JJJ.
yeah im sure 500 rpm would be fine. dont forget the cams would be pretty optimized for the standard rev range, so after 5,500rpm you'll probably see the power dropping off quite a bit
The pistons at least on the c230k have to be forged or the boost would be lower and you couldnt turbo at 15psi and not blow something
You see, this is why I asked originally in the thread about the cams, as I don't have an idea about them. Would I be correct in saying then, if I want another 500rpm without any disadvantages or associated problems like excess power drop off I should look into getting another set of cams?
JJJ.
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