R2D2

I'm a lurker here who lives in the UK and owns a C180k 2004 with a M271 engine.

I have the possibility of changing the standard kompressor on my C180k for the C230K one. Both engines are the 1.8 M271 but in difference stages of tune. Given that my car has allegedly 143bhp and the C230k had with this engine 193bhp should I change it. Miro has explored the differences in the M271 engine variants and has written elsewhere the following:

""C180K, C200K conversion to C230K with M271 series 240, 246, 248

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After many hours of sifting through the data and checking 6 VINS against each other I can suggest the following findings about the M271.

* If the engine is 2005 spec then it will be specially upgraded already with low noise parts that were recently introduced.

* In all M271 2005 the 5 speed transmission is identical

* In all M271 the crankcase and 5 speed auto slip ring are identical

* all results exclude CGI and SLK for now.

DOES NOT APPLY TO CGI
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[series 240, 246, 248 only]


C180K, C200K and C230K differ in the following ways
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- piston
- supercharger (only 2 models - one for 230K and one for others.
- ECU (engine control unit)
- Some differences in intercooler and hoses are possible with year of build.

= 140Kw in total without pulley mods

RESULT
--------
In some cases that means 20-40Kw improvement.

CAVEAT
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This mod uses only MB parts and should only be done with informed risk and has no implied warranty.
__________________
Modz ... enjoy the difference. www.benzmodz.com""


I wrote elsewhere that:

The M271 engine has a bore of 82mm and a stoke of 85mm
The C180 has a compression ratio of 10.2:1 and prodcues 105kw (143bhp)
The C200 has a compression ratio of 9.5:1 and produces 120kw
The C230k has a compression ratio of 8.7:1 and produces 141kw (193bhp)

So what I need to know is what chance is there of my engine exploding if I chuck lots more air at it with a bigger supercharger?? Will having the higher compression ratio cause a problem??

All comments welcome.

BTW this is my car.

BadAssC230k

I have not heard about one with an M271 motor, upgrading their S/c. Not sure how or what it would be upgraded to, unless it was a custom s/c. however, I do know of boost kits, pulleys, ecu tunes, etc. You can get away with doing a custom intake, as a few of the members have done. However, with that, you can adjust your AFR [once intake has comepleted] to accomidate for the new intake.

goodluck in your findings and be sure to keep us posted.

mig888

Did you send me a message about intakes? PM me here let me see if I can help you. Interesting findings if it's all true...

R2D2

PM sent! The C180k and C200k use Kompressor A271 090 2080 but the C230k which you guys drive has A271 090 2180 -this is the one I'm looking at!

Boom vang

As I understand the C230K has lower compression to prevent pre-detonation (pinging and knocking) because of the higher boast caused from the larger S/C.

If you just put a bigger S/C on your higher compression engine the ECU in conjunction with the knock sensor will have to retard the timing and thus you will not be getting extra power out it in the long run. If you don't retard the timing the valves will be burnt away from the pre-detonation over the long term.

You have to look at the engine as a complete unit and there are reasons why things are designed the way they are.

R2D2

Thankyou. Is the ECU capable of sorting out the timing/predetonation if it is remapped?

Boom vang

It (the timing ) will have to be retarded (not Borat speak) so much that you probably won't get much added power and driveability will not be that great. The car will probably not have a smooth power curve across all RPM's

Hence why the lower compression for the higher output engine

R2D2

Thats very helpful input . Thanks.

C230 Sport Coup

I think just chipping woulf get you a good increase in power.

R2D2

I got Upsolute to do that and it added hardly anything.